
The periodic task unneccessarily lists Heat stacks in the global tenant (across all tenants) which the Magnum service user may lack permission for. Also, the most restrictive way to let it use global stack-list is chose a Keystone role and open that operation to any user in any project holding that role. This commit substitutes a direct lookup of all bays' stack_id attributes for this global stack list. This direct lookup will yield the same net result. In order to get the neccessary permissions it will use each bay's stored Keystone trust to act on behalf of the bay's creating user. Co-Authored-By: Jiri Suchomel <jiri.suchomel@suse.com> Closes-Bug: #1589955 Change-Id: I67b176c137c463e37e037970cc4e468d51db30c9
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=================
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Magnum User Guide
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=================
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This guide is intended for users who use Magnum to deploy and manage clusters
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of hosts for a Container Orchestration Engine. It describes the infrastructure
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that Magnum creates and how to work with them.
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Section 1-3 describe Magnum itself, including an overview, the CLI and Horizon
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interface. Section 4-8 describe the Container Orchestration Engine's supported
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along with a guide on how to select one that best meets your needs. Section
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9-14 describe the low level OpenStack infrastructure that is created and
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managed by Magnum to support the Container Orchestration Engine's.
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========
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Contents
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========
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#. `Overview`_
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#. `Python Client`_
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#. `Horizon Interface`_
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#. `Bay Drivers`
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#. `Choosing a COE`_
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#. `Native clients`_
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#. `Kubernetes`_
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#. `Swarm`_
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#. `Mesos`_
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#. `Transport Layer Security`_
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#. `Networking`_
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#. `High Availability`_
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#. `Scaling`_
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#. `Storage`_
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#. `Image Management`_
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#. `Notification`_
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===========
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Terminology
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===========
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Bay
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A bay is the construct in which Magnum launches container orchestration
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engines. After a bay has been created the user is able to add containers to
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it either directly, or in the case of the Kubernetes container orchestration
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engine within pods - a logical construct specific to that implementation. A
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bay is created based on a baymodel.
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Baymodel
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A baymodel in Magnum is roughly equivalent to a flavor in Nova. It acts as a
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template that defines options such as the container orchestration engine,
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keypair and image for use when Magnum is creating bays using the given
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baymodel.
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Container Orchestration Engine (COE)
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A container orchestration engine manages the lifecycle of one or more
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containers, logically represented in Magnum as a bay. Magnum supports a
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number of container orchestration engines, each with their own pros and cons,
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including Docker Swarm, Kubernetes, and Mesos.
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========
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Overview
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========
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*To be filled in*
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Magnum rationale, concept, compelling features
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BayModel
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---------
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A baymodel is a collection of parameters to describe how a bay can be
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constructed. Some parameters are relevant to the infrastructure of
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the bay, while others are for the particular COE. In a typical
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workflow, a user would create a baymodel, then create one or more bays
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using the baymodel. A cloud provider can also define a number of
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baymodels and provide them to the users. A baymodel cannot be updated
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or deleted if a bay using this baymodel still exists.
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The definition and usage of the parameters of a baymodel are as follows.
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They are loosely grouped as: mandatory, infrastructure, COE specific.
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--coe \<coe\>
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Specify the Container Orchestration Engine to use. Supported
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COE's include 'kubernetes', 'swarm', 'mesos'. If your environment
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has additional bay drivers installed, refer to the bay driver
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documentation for the new COE names. This is a mandatory parameter
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and there is no default value.
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--image-id \<image-id\>
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The name or UUID of the base image in Glance to boot the servers for
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the bay. The image must have the attribute 'os-distro' defined
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as appropriate for the bay driver. For the currently supported
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images, the os-distro names are:
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========== =====================
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COE os-distro
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========== =====================
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Kubernetes Fedora-atomic, CoreOS
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Swarm Fedora-atomic
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Mesos Ubuntu
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========== =====================
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This is a mandatory parameter and there is no default value.
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--keypair-id \<keypair-id\>
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The name or UUID of the SSH keypair to configure in the bay servers
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for ssh access. You will need the key to be able to ssh to the
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servers in the bay. The login name is specific to the bay
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driver. This is a mandatory parameter and there is no default value.
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--external-network-id \<external-network-id\>
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The name or network ID of a Neutron network to provide connectivity
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to the external internet for the bay. This network must have a
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route to external internet. The servers in the bay will be
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connected to a private network and Magnum will create a router
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between this private network and the external network. This will
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allow the servers to download images, access discovery service, etc,
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and the containers to install packages, etc. In the opposite
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direction, floating IP's will be allocated from the external network
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to provide access from the external internet to servers and the
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container services hosted in the bay. This is a mandatory parameter
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and there is no default value.
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--name \<name\>
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Name of the baymodel to create. The name does not have to be
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unique. If multiple baymodels have the same name, you will need to
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use the UUID to select the baymodel when creating a bay or updating,
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deleting a baymodel. If a name is not specified, a random name will
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be generated using a string and a number, for example "pi-13-model".
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--public
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Access to a baymodel is normally limited to the admin, owner or users
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within the same tenant as the owners. Setting this flag
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makes the baymodel public and accessible by other users. The default is
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not public.
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--server-type \<server-type\>
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The servers in the bay can be VM or baremetal. This parameter selects
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the type of server to create for the bay. The default is 'vm' and
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currently this is the only supported server type.
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--network-driver \<network-driver\>
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The name of a network driver for providing the networks for the
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containers. Note that this is different and separate from the Neutron
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network for the bay. The operation and networking model are specific
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to the particular driver; refer to the `Networking`_ section for more
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details. Supported network drivers and the default driver are:
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=========== ================= ========
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COE Network-Driver Default
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=========== ================= ========
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Kubernetes Flannel Flannel
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Swarm Docker, Flannel Flannel
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Mesos Docker Docker
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=========== ================= ========
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--volume-driver \<volume-driver\>
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The name of a volume driver for managing the persistent storage for
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the containers. The functionality supported are specific to the
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driver. Supported volume drivers and the default driver are:
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============= ============= ===========
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COE Volume-Driver Default
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============= ============= ===========
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Kubernetes Cinder No Driver
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Swarm Rexray No Driver
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Mesos Rexray No Driver
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============= ============= ===========
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--dns-nameserver \<dns-nameserver\>
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The DNS nameserver for the servers and containers in the bay to use.
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This is configured in the private Neutron network for the bay. The
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default is '8.8.8.8'.
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--flavor-id \<flavor-id\>
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The nova flavor id for booting the node servers. The default
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is 'm1.small'.
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--master-flavor-id \<master-flavor-id\>
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The nova flavor id for booting the master or manager servers. The
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default is 'm1.small'.
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--http-proxy \<http-proxy\>
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The IP address for a proxy to use when direct http access from the
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servers to sites on the external internet is blocked. This may
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happen in certain countries or enterprises, and the proxy allows the
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servers and containers to access these sites. The format is a URL
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including a port number. The default is 'None'.
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--https-proxy \<https-proxy\>
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The IP address for a proxy to use when direct https access from the
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servers to sites on the external internet is blocked. This may
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happen in certain countries or enterprises, and the proxy allows the
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servers and containers to access these sites. The format is a URL
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including a port number. The default is 'None'.
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--no-proxy \<no-proxy\>
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When a proxy server is used, some sites should not go through the
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proxy and should be accessed normally. In this case, you can
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specify these sites as a comma separated list of IP's. The default
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is 'None'.
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--docker-volume-size \<docker-volume-size\>
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The size in GB for the local storage on each server for the Docker
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daemon to cache the images and host the containers. Cinder volumes
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provide the storage. The default is 25 GB. For the 'devicemapper'
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storage driver, the minimum value is 3GB. For the 'overlay' storage
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driver, the minimum value is 1GB.
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--docker-storage-driver \<docker-storage-driver\>
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The name of a driver to manage the storage for the images and the
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container's writable layer. The supported drivers are 'devicemapper'
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and 'overlay'. The default is 'devicemapper'.
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--labels \<KEY1=VALUE1,KEY2=VALUE2;KEY3=VALUE3...\>
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Arbitrary labels in the form of key=value pairs. The accepted keys
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and valid values are defined in the bay drivers. They are used as a
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way to pass additional parameters that are specific to a bay driver.
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Refer to the subsection on labels for a list of the supported
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key/value pairs and their usage.
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--tls-disabled
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Transport Layer Security (TLS) is normally enabled to secure the
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bay. In some cases, users may want to disable TLS in the bay, for
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instance during development or to troubleshoot certain problems.
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Specifying this parameter will disable TLS so that users can access
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the COE endpoints without a certificate. The default is TLS
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enabled.
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--registry-enabled
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Docker images by default are pulled from the public Docker registry,
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but in some cases, users may want to use a private registry. This
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option provides an alternative registry based on the Registry V2:
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Magnum will create a local registry in the bay backed by swift to
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host the images. Refer to
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`Docker Registry 2.0 <https://github.com/docker/distribution>`_
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for more details. The default is to use the public registry.
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Labels
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------
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*To be filled in*
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Bay
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---
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*To be filled in*
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=============
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Python Client
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=============
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Installation
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------------
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Follow the instructions in the OpenStack Installation Guide to enable the
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repositories for your distribution:
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* `RHEL/CentOS/Fedora
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<http://docs.openstack.org/liberty/install-guide-rdo/>`_
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* `Ubuntu/Debian
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<http://docs.openstack.org/liberty/install-guide-ubuntu/>`_
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* `openSUSE/SUSE Linux Enterprise
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<http://docs.openstack.org/liberty/install-guide-obs/>`_
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Install using distribution packages for RHEL/CentOS/Fedora::
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$ sudo yum install python-magnumclient
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Install using distribution packages for Ubuntu/Debian::
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$ sudo apt-get install python-magnumclient
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Install using distribution packages for OpenSuSE and SuSE Enterprise Linux::
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$ sudo zypper install python-magnumclient
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Verifying installation
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----------------------
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Execute the `magnum` command with the `--version` argument to confirm that the
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client is installed and in the system path::
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$ magnum --version
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1.1.0
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Note that the version returned may differ from the above, 1.1.0 was the latest
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available version at the time of writing.
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Using the command-line client
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-----------------------------
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Refer to the `OpenStack Command-Line Interface Reference
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<http://docs.openstack.org/cli-reference/magnum.html>`_ for a full list of the
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commands supported by the `magnum` command-line client.
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=================
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Horizon Interface
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=================
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*To be filled in with screenshots*
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===========
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Bay Drivers
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===========
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A bay driver is a collection of python code, heat templates, scripts,
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images, and documents for a particular COE on a particular
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distro. Magnum presents the concept of baymodels and bays. The
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implementation for a particular bay type is provided by the bay driver.
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In other words, the bay driver provisions and manages the infrastructure
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for the COE. Magnum includes default drivers for the following
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COE and distro pairs:
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+------------+---------------+
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| COE | distro |
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+============+===============+
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| Kubernetes | Fedora Atomic |
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+------------+---------------+
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| Kubernetes | CoreOS |
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+------------+---------------+
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| Swarm | Fedora Atomic |
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+------------+---------------+
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| Mesos | Ubuntu |
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+------------+---------------+
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Magnum is designed to accommodate new bay drivers to support custom
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COE's and this section describes how a new bay driver can be
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constructed and enabled in Magnum.
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Directory structure
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-------------------
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Magnum expects the components to be organized in the following
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directory structure under the directory 'drivers'::
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COE_Distro/
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image/
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templates/
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api.py
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driver.py
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monitor.py
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scale.py
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template_def.py
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version.py
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The minimum required components are:
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driver.py
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Python code that implements the controller operations for
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the particular COE. The driver must implement:
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Currently supported: ``bay_create``, ``bay_update``, ``bay_delete``.
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templates
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A directory of orchestration templates for managing the lifecycle
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of bays, including creation, configuration, update, and deletion.
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Currently only Heat templates are supported, but in the future
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other orchestration mechanism such as Ansible may be supported.
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template_def.py
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Python code that maps the parameters from the baymodel to the
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input parameters for the orchestration and invokes
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the orchestration in the templates directory.
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version.py
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Tracks the latest version of the driver in this directory.
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This is defined by a ``version`` attribute and is represented in the
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form of ``1.0.0``. It should also include a ``Driver`` attribute with
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descriptive name such as ``fedora_swarm_atomic``.
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The remaining components are optional:
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image
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Instructions for obtaining or building an image suitable for the COE.
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api.py
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Python code to interface with the COE.
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monitor.py
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Python code to monitor the resource utilization of the bay.
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scale.py
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Python code to scale the bay by adding or removing nodes.
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Sample bay driver
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-----------------
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To help developers in creating new COE drivers, a minimal bay driver
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is provided as an example. The 'docker' bay driver will simply deploy
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a single VM running Ubuntu with the latest Docker version installed.
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It is not a true cluster, but the simplicity will help to illustrate
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the key concepts.
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*To be filled in*
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Installing a bay driver
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-----------------------
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*To be filled in*
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==============
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Choosing a COE
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==============
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Magnum supports a variety of COE options, and allows more to be added over time
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as they gain popularity. As an operator, you may choose to support the full
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variety of options, or you may want to offer a subset of the available choices.
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Given multiple choices, your users can run one or more bays, and each may use
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a different COE. For example, I might have multiple bays that use Kubernetes,
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and just one bay that uses Swarm. All of these bays can run concurrently, even
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though they use different COE software.
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Choosing which COE to use depends on what tools you want to use to manage your
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containers once you start your app. If you want to use the Docker tools, you
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may want to use the Swarm bay type. Swarm will spread your containers across
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the various nodes in your bay automatically. It does not monitor the health of
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your containers, so it can't restart them for you if they stop. It will not
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automatically scale your app for you (as of Swarm version 1.2.2). You may view
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this as a plus. If you prefer to manage your application yourself, you might
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prefer swarm over the other COE options.
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Kubernetes (as of v1.2) is more sophisticated than Swarm (as of v1.2.2). It
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offers an attractive YAML file description of a pod, which is a grouping of
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containers that run together as part of a distributed application. This file
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format allows you to model your application deployment using a declarative
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style. It has support for auto scaling and fault recovery, as well as features
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that allow for sophisticated software deployments, including canary deploys
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and blue/green deploys. Kubernetes is very popular, especially for web
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applications.
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Apache Mesos is a COE that has been around longer than Kubernetes or Swarm. It
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allows for a variety of different frameworks to be used along with it,
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including Marathon, Aurora, Chronos, Hadoop, and `a number of others.
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<http://mesos.apache.org/documentation/latest/frameworks/>`_
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The Apache Mesos framework design can be used to run alternate COE software
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directly on Mesos. Although this approach is not widely used yet, it may soon
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be possible to run Mesos with Kubernetes and Swarm as frameworks, allowing
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you to share the resources of a bay between multiple different COEs. Until
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this option matures, we encourage Magnum users to create multiple bays, and
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use the COE in each bay that best fits the anticipated workload.
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Finding the right COE for your workload is up to you, but Magnum offers you a
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choice to select among the prevailing leading options. Once you decide, see
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the next sections for examples of how to create a bay with your desired COE.
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==============
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Native clients
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==============
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*To be filled in*
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==========
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Kubernetes
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==========
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Kubernetes uses a range of terminology that we refer to in this guide. We
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define these common terms for your reference:
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Pod
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When using the Kubernetes container orchestration engine, a pod is the
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smallest deployable unit that can be created and managed. A pod is a
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co-located group of application containers that run with a shared context.
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When using Magnum, pods are created and managed within bays. Refer to the
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`pods section
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<http://kubernetes.io/v1.0/docs/user-guide/pods.html>`_ in the `Kubernetes
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User Guide`_ for more information.
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Replication controller
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A replication controller is used to ensure that at any given time a certain
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number of replicas of a pod are running. Pods are automatically created and
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deleted by the replication controller as necessary based on a template to
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ensure that the defined number of replicas exist. Refer to the `replication
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controller section
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<http://kubernetes.io/v1.0/docs/user-guide/replication-controller.html>`_ in
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the `Kubernetes User Guide`_ for more information.
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Service
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A service is an additional layer of abstraction provided by the Kubernetes
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container orchestration engine which defines a logical set of pods and a
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policy for accessing them. This is useful because pods are created and
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deleted by a replication controller, for example, other pods needing to
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discover them can do so via the service abstraction. Refer to the
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`services section
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<http://kubernetes.io/v1.0/docs/user-guide/services.html>`_ in the
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`Kubernetes User Guide`_ for more information.
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.. _Kubernetes User Guide: http://kubernetes.io/v1.0/docs/user-guide/
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When Magnum deploys a Kubernetes bay, it uses parameters defined in the
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baymodel and specified on the bay-create command, for example::
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magnum baymodel-create --name k8sbaymodel \
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--image-id fedora-atomic-latest \
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--keypair-id testkey \
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--external-network-id public \
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--dns-nameserver 8.8.8.8 \
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--flavor-id m1.small \
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--docker-volume-size 5 \
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--network-driver flannel \
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--coe kubernetes
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magnum bay-create --name k8sbay \
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--baymodel k8sbaymodel \
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|
--master-count 3 \
|
|
--node-count 8
|
|
|
|
Refer to the `Baymodel`_ and `Bay`_ sections for the full list of parameters.
|
|
Following are further details relevant to a Kubernetes bay:
|
|
|
|
Number of masters (master-count)
|
|
Specified in the bay-create command to indicate how many servers will
|
|
run as master in the bay. Having more than one will provide high
|
|
availability. The masters will be in a load balancer pool and the
|
|
virtual IP address (VIP) of the load balancer will serve as the
|
|
Kubernetes API endpoint. For external access, a floating IP
|
|
associated with this VIP is available and this is the endpoint
|
|
shown for Kubernetes in the 'bay-show' command.
|
|
|
|
Number of nodes (node-count)
|
|
Specified in the bay-create command to indicate how many servers will
|
|
run as node in the bay to host the users' pods. The nodes are registered
|
|
in Kubernetes using the Nova instance name.
|
|
|
|
Network driver (network-driver)
|
|
Specified in the baymodel to select the network driver.
|
|
The supported and default network driver is 'flannel', an overlay
|
|
network providing a flat network for all pods. Refer to the
|
|
`Networking`_ section for more details.
|
|
|
|
Volume driver (volume-driver)
|
|
Specified in the baymodel to select the volume driver. The supported
|
|
volume driver is 'cinder', allowing Cinder volumes to be mounted in
|
|
containers for use as persistent storage. Data written to these volumes
|
|
will persist after the container exits and can be accessed again from other
|
|
containers, while data written to the union file system hosting the container
|
|
will be deleted. Refer to the `Storage`_ section for more details.
|
|
|
|
Storage driver (docker-storage-driver)
|
|
Specified in the baymodel to select the Docker storage driver. The
|
|
supported storage drivers are 'devicemapper' and 'overlay', with
|
|
'devicemapper' being the default. You may get better performance with
|
|
the overlay driver depending on your use patterns, with the requirement
|
|
that SELinux must be disabled inside the containers, although it still runs
|
|
in enforcing mode on the bay servers. Magnum will create a Cinder volume
|
|
for each node, mount it on the node and configure it as a logical
|
|
volume named 'docker'. The Docker daemon will run the selected device
|
|
driver to manage this logical volume and host the container writable
|
|
layer there. Refer to the `Storage`_ section for more details.
|
|
|
|
Image (image-id)
|
|
Specified in the baymodel to indicate the image to boot the servers.
|
|
The image binary is loaded in Glance with the attribute
|
|
'os_distro = fedora-atomic'.
|
|
Current supported images are Fedora Atomic (download from `Fedora
|
|
<https://alt.fedoraproject.org/pub/alt/atomic/stable/Cloud-Images/x86_64/Images>`_ )
|
|
and CoreOS (download from `CoreOS
|
|
<http://beta.release.core-os.net/amd64-usr/current/coreos_production_openstack_image.img.bz2>`_ )
|
|
|
|
TLS (tls-disabled)
|
|
Transport Layer Security is enabled by default, so you need a key and
|
|
signed certificate to access the Kubernetes API and CLI. Magnum
|
|
handles its own key and certificate when interfacing with the
|
|
Kubernetes bay. In development mode, TLS can be disabled. Refer to
|
|
the 'Transport Layer Security'_ section for more details.
|
|
|
|
What runs on the servers
|
|
The servers for Kubernetes master host containers in the 'kube-system'
|
|
name space to run the Kubernetes proxy, scheduler and controller manager.
|
|
The masters will not host users' pods. Kubernetes API server, docker
|
|
daemon, etcd and flannel run as systemd services. The servers for
|
|
Kubernetes node also host a container in the 'kube-system' name space
|
|
to run the Kubernetes proxy, while Kubernetes kubelet, docker daemon
|
|
and flannel run as systemd services.
|
|
|
|
Log into the servers
|
|
You can log into the master servers using the login 'minion' and the
|
|
keypair specified in the baymodel.
|
|
|
|
External load balancer for services
|
|
-----------------------------------
|
|
|
|
All Kubernetes pods and services created in the bay are assigned IP
|
|
addresses on a private container network so they can access each other
|
|
and the external internet. However, these IP addresses are not
|
|
accessible from an external network.
|
|
|
|
To publish a service endpoint externally so that the service can be
|
|
accessed from the external network, Kubernetes provides the external
|
|
load balancer feature. This is done by simply specifying in the
|
|
service manifest the attribute "type: LoadBalancer". Magnum enables
|
|
and configures the Kubernetes plugin for OpenStack so that it can
|
|
interface with Neutron and manage the necessary networking resources.
|
|
|
|
When the service is created, Kubernetes will add an external load
|
|
balancer in front of the service so that the service will have an
|
|
external IP address in addition to the internal IP address on the
|
|
container network. The service endpoint can then be accessed with
|
|
this external IP address. Kubernetes handles all the life cycle
|
|
operations when pods are modified behind the service and when the
|
|
service is deleted.
|
|
|
|
Refer to the document `Kubernetes external load balancer
|
|
<https://github.com/openstack/magnum/blob/master/doc/source/dev/kubernetes-load-balancer.rst>`_
|
|
for more details.
|
|
|
|
|
|
=====
|
|
Swarm
|
|
=====
|
|
|
|
A Swarm bay is a pool of servers running Docker daemon that is
|
|
managed as a single Docker host. One or more Swarm managers accepts
|
|
the standard Docker API and manage this pool of servers.
|
|
Magnum deploys a Swarm bay using parameters defined in
|
|
the baymodel and specified on the 'bay-create' command, for example::
|
|
|
|
magnum baymodel-create --name swarmbaymodel \
|
|
--image-id fedora-atomic-latest \
|
|
--keypair-id testkey \
|
|
--external-network-id public \
|
|
--dns-nameserver 8.8.8.8 \
|
|
--flavor-id m1.small \
|
|
--docker-volume-size 5 \
|
|
--coe swarm
|
|
|
|
magnum bay-create --name swarmbay \
|
|
--baymodel swarmbaymodel \
|
|
--master-count 3 \
|
|
--node-count 8
|
|
|
|
Refer to the `Baymodel`_ and `Bay`_ sections for the full list of parameters.
|
|
Following are further details relevant to Swarm:
|
|
|
|
What runs on the servers
|
|
There are two types of servers in the Swarm bay: managers and nodes.
|
|
The Docker daemon runs on all servers. On the servers for manager,
|
|
the Swarm manager is run as a Docker container on port 2376 and this
|
|
is initiated by the systemd service swarm-manager. Etcd is also run
|
|
on the manager servers for discovery of the node servers in the bay.
|
|
On the servers for node, the Swarm agent is run as a Docker
|
|
container on port 2375 and this is initiated by the systemd service
|
|
swarm-agent. On start up, the agents will register themselves in
|
|
etcd and the managers will discover the new node to manage.
|
|
|
|
Number of managers (master-count)
|
|
Specified in the bay-create command to indicate how many servers will
|
|
run as managers in the bay. Having more than one will provide high
|
|
availability. The managers will be in a load balancer pool and the
|
|
load balancer virtual IP address (VIP) will serve as the Swarm API
|
|
endpoint. A floating IP associated with the load balancer VIP will
|
|
serve as the external Swarm API endpoint. The managers accept
|
|
the standard Docker API and perform the corresponding operation on the
|
|
servers in the pool. For instance, when a new container is created,
|
|
the managers will select one of the servers based on some strategy
|
|
and schedule the containers there.
|
|
|
|
Number of nodes (node-count)
|
|
Specified in the bay-create command to indicate how many servers will
|
|
run as nodes in the bay to host your Docker containers. These servers
|
|
will register themselves in etcd for discovery by the managers, and
|
|
interact with the managers. Docker daemon is run locally to host
|
|
containers from users.
|
|
|
|
Network driver (network-driver)
|
|
Specified in the baymodel to select the network driver. The supported
|
|
drivers are 'docker' and 'flannel', with 'docker' as the default.
|
|
With the 'docker' driver, containers are connected to the 'docker0'
|
|
bridge on each node and are assigned local IP address. With the
|
|
'flannel' driver, containers are connected to a flat overlay network
|
|
and are assigned IP address by Flannel. Refer to the `Networking`_
|
|
section for more details.
|
|
|
|
Volume driver (volume-driver)
|
|
Specified in the baymodel to select the volume driver to provide
|
|
persistent storage for containers. The supported volume driver is
|
|
'rexray'. The default is no volume driver. When 'rexray' or other
|
|
volume driver is deployed, you can use the Docker 'volume' command to
|
|
create, mount, unmount, delete volumes in containers. Cinder block
|
|
storage is used as the backend to support this feature.
|
|
Refer to the `Storage`_ section for more details.
|
|
|
|
Storage driver (docker-storage-driver)
|
|
Specified in the baymodel to select the Docker storage driver. The
|
|
supported storage driver are 'devicemapper' and 'overlay', with
|
|
'devicemapper' being the default. You may get better performance with
|
|
the 'overlay' driver depending on your use patterns, with the requirement
|
|
that SELinux must be disabled inside the containers, although it still runs
|
|
in enforcing mode on the bay servers. Magnum will create a Cinder volume
|
|
for each node and attach it as a device. Then depending on the driver,
|
|
additional configuration is performed to make the volume available to
|
|
the particular driver. For instance, 'devicemapper' uses LVM; therefore
|
|
Magnum will create physical volume and logical volume using the attached
|
|
device. Refer to the `Storage`_ section for more details.
|
|
|
|
Image (image-id)
|
|
Specified in the baymodel to indicate the image to boot the servers
|
|
for the Swarm manager and node.
|
|
The image binary is loaded in Glance with the attribute
|
|
'os_distro = fedora-atomic'.
|
|
Current supported image is Fedora Atomic (download from `Fedora
|
|
<https://alt.fedoraproject.org/pub/alt/atomic/stable/Cloud-Images/x86_64/Images>`_ )
|
|
|
|
TLS (tls-disabled)
|
|
Transport Layer Security is enabled by default to secure the Swarm API for
|
|
access by both the users and Magnum. You will need a key and a
|
|
signed certificate to access the Swarm API and CLI. Magnum
|
|
handles its own key and certificate when interfacing with the
|
|
Swarm bay. In development mode, TLS can be disabled. Refer to
|
|
the 'Transport Layer Security'_ section for details on how to create your
|
|
key and have Magnum sign your certificate.
|
|
|
|
Log into the servers
|
|
You can log into the manager and node servers with the account 'fedora' and
|
|
the keypair specified in the baymodel.
|
|
|
|
|
|
=====
|
|
Mesos
|
|
=====
|
|
|
|
A Mesos bay consists of a pool of servers running as Mesos agents,
|
|
managed by a set of servers running as Mesos masters. Mesos manages
|
|
the resources from the agents but does not itself deploy containers.
|
|
Instead, one of more Mesos frameworks running on the Mesos bay would
|
|
accept user requests on their own endpoint, using their particular
|
|
API. These frameworks would then negotiate the resources with Mesos
|
|
and the containers are deployed on the servers where the resources are
|
|
offered.
|
|
|
|
Magnum deploys a Mesos bay using parameters defined in the baymodel
|
|
and specified on the 'bay-create' command, for example::
|
|
|
|
magnum baymodel-create --name mesosbaymodel \
|
|
--image-id ubuntu-mesos \
|
|
--keypair-id testkey \
|
|
--external-network-id public \
|
|
--dns-nameserver 8.8.8.8 \
|
|
--flavor-id m1.small \
|
|
--coe mesos
|
|
|
|
magnum bay-create --name mesosbay \
|
|
--baymodel mesosbaymodel \
|
|
--master-count 3 \
|
|
--node-count 8
|
|
|
|
Refer to the `Baymodel`_ and `Bay`_ sections for the full list of
|
|
parameters. Following are further details relevant to Mesos:
|
|
|
|
What runs on the servers
|
|
There are two types of servers in the Mesos bay: masters and agents.
|
|
The Docker daemon runs on all servers. On the servers for master,
|
|
the Mesos master is run as a process on port 5050 and this is
|
|
initiated by the upstart service 'mesos-master'. Zookeeper is also
|
|
run on the master servers, initiated by the upstart service
|
|
'zookeeper'. Zookeeper is used by the master servers for electing
|
|
the leader among the masters, and by the agent servers and
|
|
frameworks to determine the current leader. The framework Marathon
|
|
is run as a process on port 8080 on the master servers, initiated by
|
|
the upstart service 'marathon'. On the servers for agent, the Mesos
|
|
agent is run as a process initiated by the upstart service
|
|
'mesos-agent'.
|
|
|
|
Number of master (master-count)
|
|
Specified in the bay-create command to indicate how many servers
|
|
will run as masters in the bay. Having more than one will provide
|
|
high availability. If the load balancer option is specified, the
|
|
masters will be in a load balancer pool and the load balancer
|
|
virtual IP address (VIP) will serve as the Mesos API endpoint. A
|
|
floating IP associated with the load balancer VIP will serve as the
|
|
external Mesos API endpoint.
|
|
|
|
Number of agents (node-count)
|
|
Specified in the bay-create command to indicate how many servers
|
|
will run as Mesos agent in the bay. Docker daemon is run locally to
|
|
host containers from users. The agents report their available
|
|
resources to the master and accept request from the master to deploy
|
|
tasks from the frameworks. In this case, the tasks will be to
|
|
run Docker containers.
|
|
|
|
Network driver (network-driver)
|
|
Specified in the baymodel to select the network driver. Currently
|
|
'docker' is the only supported driver: containers are connected to
|
|
the 'docker0' bridge on each node and are assigned local IP address.
|
|
Refer to the `Networking`_ section for more details.
|
|
|
|
Volume driver (volume-driver)
|
|
Specified in the baymodel to select the volume driver to provide
|
|
persistent storage for containers. The supported volume driver is
|
|
'rexray'. The default is no volume driver. When 'rexray' or other
|
|
volume driver is deployed, you can use the Docker 'volume' command to
|
|
create, mount, unmount, delete volumes in containers. Cinder block
|
|
storage is used as the backend to support this feature.
|
|
Refer to the `Storage`_ section for more details.
|
|
|
|
Storage driver (docker-storage-driver)
|
|
This is currently not supported for Mesos.
|
|
|
|
Image (image-id)
|
|
|
|
Specified in the baymodel to indicate the image to boot the servers
|
|
for the Mesos master and agent. The image binary is loaded in
|
|
Glance with the attribute 'os_distro = ubuntu'. You can download
|
|
the `ready-built image
|
|
<https://fedorapeople.org/groups/magnum/ubuntu-14.04.3-mesos-0.25.0.qcow2>`_,
|
|
or you can create the image as described below in the `Building
|
|
Mesos image`_ section.
|
|
|
|
TLS (tls-disabled)
|
|
Transport Layer Security is currently not implemented yet for Mesos.
|
|
|
|
Log into the servers
|
|
You can log into the manager and node servers with the account
|
|
'ubuntu' and the keypair specified in the baymodel.
|
|
|
|
|
|
Building Mesos image
|
|
--------------------
|
|
|
|
The boot image for Mesos bay is an Ubuntu 14.04 base image with the
|
|
following middleware pre-installed:
|
|
|
|
- ``docker``
|
|
- ``zookeeper``
|
|
- ``mesos``
|
|
- ``marathon``
|
|
|
|
The bay driver provides two ways to create this image, as follows.
|
|
|
|
Diskimage-builder
|
|
++++++++++++++++++
|
|
|
|
To run the `diskimage-builder
|
|
<http://docs.openstack.org/developer/diskimage-builder>`__ tool
|
|
manually, use the provided `elements
|
|
<http://git.openstack.org/cgit/openstack/magnum/tree/magnum/drivers/mesos_ubuntu_v1/image/mesos/>`__.
|
|
Following are the typical steps to use the diskimage-builder tool on
|
|
an Ubuntu server::
|
|
|
|
$ sudo apt-get update
|
|
$ sudo apt-get install git qemu-utils python-pip
|
|
|
|
$ git clone https://git.openstack.org/openstack/magnum
|
|
$ git clone https://git.openstack.org/openstack/diskimage-builder.git
|
|
$ git clone https://git.openstack.org/openstack/dib-utils.git
|
|
$ git clone https://git.openstack.org/openstack/tripleo-image-elements.git
|
|
$ git clone https://git.openstack.org/openstack/heat-templates.git
|
|
$ export PATH="${PWD}/dib-utils/bin:$PATH"
|
|
$ export ELEMENTS_PATH=tripleo-image-elements/elements:heat-templates/hot/software-config/elements:magnum/magnum/drivers/mesos_ubuntu_v1/image/mesos
|
|
$ export DIB_RELEASE=trusty
|
|
|
|
$ diskimage-builder/bin/disk-image-create ubuntu vm docker mesos \
|
|
os-collect-config os-refresh-config os-apply-config \
|
|
heat-config heat-config-script \
|
|
-o ubuntu-14.04.3-mesos-0.25.0.qcow2
|
|
|
|
Dockerfile
|
|
++++++++++
|
|
|
|
To build the image as above but within a Docker container, use the
|
|
provided `Dockerfile
|
|
<http://git.openstack.org/cgit/openstack/magnum/tree/magnum/drivers/mesos_ubuntu_v1/image/Dockerfile>`__. The
|
|
output image will be saved as '/tmp/ubuntu-mesos.qcow2'.
|
|
Following are the typical steps to run a Docker container to build the image::
|
|
|
|
$ git clone https://git.openstack.org/openstack/magnum
|
|
$ cd magnum/magnum/drivers/mesos_ubuntu_v1/image
|
|
$ sudo docker build -t magnum/mesos-builder .
|
|
$ sudo docker run -v /tmp:/output --rm -ti --privileged magnum/mesos-builder
|
|
...
|
|
Image file /output/ubuntu-mesos.qcow2 created...
|
|
|
|
|
|
Using Marathon
|
|
--------------
|
|
|
|
Marathon is a Mesos framework for long running applications. Docker
|
|
containers can be deployed via Marathon's REST API. To get the
|
|
endpoint for Marathon, run the bay-show command and look for the
|
|
property 'api_address'. Marathon's endpoint is port 8080 on this IP
|
|
address, so the web console can be accessed at::
|
|
|
|
http://<api_address>:8080/
|
|
|
|
Refer to Marathon documentation for details on running applications.
|
|
For example, you can 'post' a JSON app description to
|
|
``http://<api_address>:8080/apps`` to deploy a Docker container::
|
|
|
|
$ cat > app.json << END
|
|
{
|
|
"container": {
|
|
"type": "DOCKER",
|
|
"docker": {
|
|
"image": "libmesos/ubuntu"
|
|
}
|
|
},
|
|
"id": "ubuntu",
|
|
"instances": 1,
|
|
"cpus": 0.5,
|
|
"mem": 512,
|
|
"uris": [],
|
|
"cmd": "while sleep 10; do date -u +%T; done"
|
|
}
|
|
END
|
|
$ API_ADDRESS=$(magnum bay-show mesosbay | awk '/ api_address /{print $4}')
|
|
$ curl -X POST -H "Content-Type: application/json" \
|
|
http://${API_ADDRESS}:8080/v2/apps -d@app.json
|
|
|
|
|
|
========================
|
|
Transport Layer Security
|
|
========================
|
|
*To be filled in*
|
|
|
|
Native Client Configuration guide for each COE
|
|
|
|
==========
|
|
Networking
|
|
==========
|
|
|
|
There are two components that make up the networking in a cluster.
|
|
|
|
1. The Neutron infrastructure for the cluster: this includes the
|
|
private network, subnet, ports, routers, load balancers, etc.
|
|
|
|
2. The networking model presented to the containers: this is what the
|
|
containers see in communicating with each other and to the external
|
|
world. Typically this consists of a driver deployed on each node.
|
|
|
|
The two components are deployed and managed separately. The Neutron
|
|
infrastructure is the integration with OpenStack; therefore, it
|
|
is stable and more or less similar across different COE
|
|
types. The networking model, on the other hand, is specific to the
|
|
COE type and is still under active development in the various
|
|
COE communities, for example,
|
|
`Docker libnetwork <https://github.com/docker/libnetwork>`_ and
|
|
`Kubernetes Container Networking
|
|
<https://github.com/kubernetes/kubernetes/blob/release-1.1/docs/design/networking.md>`_.
|
|
As a result, the implementation for the networking models is evolving and
|
|
new models are likely to be introduced in the future.
|
|
|
|
For the Neutron infrastructure, the following configuration can
|
|
be set in the baymodel:
|
|
|
|
external-network-id
|
|
The external Neutron network ID to connect to this bay. This
|
|
is used to connect the cluster to the external internet, allowing
|
|
the nodes in the bay to access external URL for discovery, image
|
|
download, etc. If not specified, the default value is "public" and this
|
|
is valid for a typical devstack.
|
|
|
|
fixed-network
|
|
The Neutron network to use as the private network for the bay nodes.
|
|
If not specified, a new Neutron private network will be created.
|
|
|
|
dns-nameserver
|
|
The DNS nameserver to use for this bay. This is an IP address for
|
|
the server and it is used to configure the Neutron subnet of the
|
|
cluster (dns_nameservers). If not specified, the default DNS is
|
|
8.8.8.8, the publicly available DNS.
|
|
|
|
http-proxy, https-proxy, no-proxy
|
|
The proxy for the nodes in the bay, to be used when the cluster is
|
|
behind a firewall and containers cannot access URL's on the external
|
|
internet directly. For the parameter http-proxy and https-proxy, the
|
|
value to provide is a URL and it will be set in the environment
|
|
variable HTTP_PROXY and HTTPS_PROXY respectively in the nodes. For
|
|
the parameter no-proxy, the value to provide is an IP or list of IP's
|
|
separated by comma. Likewise, the value will be set in the
|
|
environment variable NO_PROXY in the nodes.
|
|
|
|
For the networking model to the container, the following configuration
|
|
can be set in the baymodel:
|
|
|
|
network-driver
|
|
The network driver name for instantiating container networks.
|
|
Currently, the following network drivers are supported:
|
|
|
|
+--------+-------------+-----------+-------------+
|
|
| Driver | Kubernetes | Swarm | Mesos |
|
|
+========+=============+===========+=============+
|
|
| Flannel| supported | supported | unsupported |
|
|
+--------+-------------+-----------+-------------+
|
|
| Docker | unsupported | supported | supported |
|
|
+--------+-------------+-----------+-------------+
|
|
|
|
If not specified, the default driver is Flannel for Kubernetes, and
|
|
Docker for Swarm and Mesos.
|
|
|
|
Particular network driver may require its own set of parameters for
|
|
configuration, and these parameters are specified through the labels
|
|
in the baymodel. Labels are arbitrary key=value pairs.
|
|
|
|
When Flannel is specified as the network driver, the following
|
|
optional labels can be added:
|
|
|
|
flannel_network_cidr
|
|
IPv4 network in CIDR format to use for the entire Flannel network.
|
|
If not specified, the default is 10.100.0.0/16.
|
|
|
|
flannel_network_subnetlen
|
|
The size of the subnet allocated to each host. If not specified, the
|
|
default is 24.
|
|
|
|
flannel_backend
|
|
The type of backend for Flannel. Possible values are *udp, vxlan,
|
|
host-gw*. If not specified, the default is *udp*. Selecting the
|
|
best backend depends on your networking. Generally, *udp* is
|
|
the most generally supported backend since there is little
|
|
requirement on the network, but it typically offers the lowest
|
|
performance. The *vxlan* backend performs better, but requires
|
|
vxlan support in the kernel so the image used to provision the
|
|
nodes needs to include this support. The *host-gw* backend offers
|
|
the best performance since it does not actually encapsulate
|
|
messages, but it requires all the nodes to be on the same L2
|
|
network. The private Neutron network that Magnum creates does
|
|
meet this requirement; therefore if the parameter *fixed_network*
|
|
is not specified in the baymodel, *host-gw* is the best choice for
|
|
the Flannel backend.
|
|
|
|
|
|
=================
|
|
High Availability
|
|
=================
|
|
*To be filled in*
|
|
|
|
=======
|
|
Scaling
|
|
=======
|
|
|
|
Performance tuning for periodic task
|
|
------------------------------------
|
|
|
|
Magnum's periodic task performs a `stack-get` operation on the Heat stack
|
|
underlying each of its bays. If you have a large amount of bays this can create
|
|
considerable load on the Heat API. To reduce that load you can configure Magnum
|
|
to perform one global `stack-list` per periodic task instead instead of one per
|
|
bay. This is disabled by default, both from the Heat and Magnum side since it
|
|
causes a security issue, though: any user in any tenant holding the `admin`
|
|
role can perform a global `stack-list` operation if Heat is configured to allow
|
|
it for Magnum. If you want to enable it nonetheless, proceed as follows:
|
|
|
|
1. Set `periodic_global_stack_list` in magnum.conf to `True`
|
|
(`False` by default).
|
|
|
|
2. Update heat policy to allow magnum list stacks. To this end, edit your heat
|
|
policy file, usually etc/heat/policy.json``:
|
|
|
|
.. code-block:: ini
|
|
|
|
...
|
|
stacks:global_index: "role:admin",
|
|
|
|
Now restart heat.
|
|
|
|
|
|
*To be filled in*
|
|
Include auto scaling
|
|
|
|
=======
|
|
Storage
|
|
=======
|
|
|
|
Currently Cinder provides the block storage to the containers, and the
|
|
storage is made available in two ways: as ephemeral storage and as
|
|
persistent storage.
|
|
|
|
Ephemeral storage
|
|
-----------------
|
|
|
|
The filesystem for the container consists of multiple layers from the
|
|
image and a top layer that holds the modification made by the
|
|
container. This top layer requires storage space and the storage is
|
|
configured in the Docker daemon through a number of storage options.
|
|
When the container is removed, the storage allocated to the particular
|
|
container is also deleted.
|
|
|
|
To manage this space in a flexible manner independent of the Nova
|
|
instance flavor, Magnum creates a separate Cinder block volume for each
|
|
node in the bay, mounts it to the node and configures it to be used as
|
|
ephemeral storage. Users can specify the size of the Cinder volume with
|
|
the baymodel attribute 'docker-volume-size'. The default size is 5GB.
|
|
Currently the block size is fixed at bay creation time, but future
|
|
lifecycle operations may allow modifying the block size during the
|
|
life of the bay.
|
|
|
|
To use the Cinder block storage, there is a number of Docker
|
|
storage drivers available. Only 'devicemapper' is supported as the
|
|
storage driver but other drivers such as 'OverlayFS' are being
|
|
considered. There are important trade-off between the choices
|
|
for the storage drivers that should be considered. For instance,
|
|
'OperlayFS' may offer better performance, but it may not support
|
|
the filesystem metadata needed to use SELinux, which is required
|
|
to support strong isolation between containers running in the same
|
|
bay. Using the 'devicemapper' driver does allow the use of SELinux.
|
|
|
|
|
|
Persistent storage
|
|
------------------
|
|
|
|
In some use cases, data read/written by a container needs to persist
|
|
so that it can be accessed later. To persist the data, a Cinder
|
|
volume with a filesystem on it can be mounted on a host and be made
|
|
available to the container, then be unmounted when the container exits.
|
|
|
|
Docker provides the 'volume' feature for this purpose: the user
|
|
invokes the 'volume create' command, specifying a particular volume
|
|
driver to perform the actual work. Then this volume can be mounted
|
|
when a container is created. A number of third-party volume drivers
|
|
support OpenStack Cinder as the backend, for example Rexray and
|
|
Flocker. Magnum currently supports Rexray as the volume driver for
|
|
Swarm and Mesos. Other drivers are being considered.
|
|
|
|
Kubernetes allows a previously created Cinder block to be mounted to
|
|
a pod and this is done by specifying the block ID in the pod yaml file.
|
|
When the pod is scheduled on a node, Kubernetes will interface with
|
|
Cinder to request the volume to be mounted on this node, then
|
|
Kubernetes will launch the Docker container with the proper options to
|
|
make the filesystem on the Cinder volume accessible to the container
|
|
in the pod. When the pod exits, Kubernetes will again send a request
|
|
to Cinder to unmount the volume's filesystem, making it available to be
|
|
mounted on other nodes.
|
|
|
|
Magnum supports these features to use Cinder as persistent storage
|
|
using the baymodel attribute 'volume-driver' and the support matrix
|
|
for the COE types is summarized as follows:
|
|
|
|
+--------+-------------+-------------+-------------+
|
|
| Driver | Kubernetes | Swarm | Mesos |
|
|
+========+=============+=============+=============+
|
|
| cinder | supported | unsupported | unsupported |
|
|
+--------+-------------+-------------+-------------+
|
|
| rexray | unsupported | supported | supported |
|
|
+--------+-------------+-------------+-------------+
|
|
|
|
Following are some examples for using Cinder as persistent storage.
|
|
|
|
Using Cinder in Kubernetes
|
|
++++++++++++++++++++++++++
|
|
|
|
**NOTE:** This feature requires Kubernetes version 1.1.1 or above and
|
|
Docker version 1.8.3 or above. The public Fedora image from Atomic
|
|
currently meets this requirement.
|
|
|
|
**NOTE:** The following steps are a temporary workaround, and Magnum's
|
|
development team is working on a long term solution to automate these steps.
|
|
|
|
1. Create the baymodel.
|
|
|
|
Specify 'cinder' as the volume-driver for Kubernetes::
|
|
|
|
magnum baymodel-create --name k8sbaymodel \
|
|
--image-id fedora-23-atomic-7 \
|
|
--keypair-id testkey \
|
|
--external-network-id public \
|
|
--dns-nameserver 8.8.8.8 \
|
|
--flavor-id m1.small \
|
|
--docker-volume-size 5 \
|
|
--network-driver flannel \
|
|
--coe kubernetes \
|
|
--volume-driver cinder
|
|
|
|
2. Create the bay::
|
|
|
|
magnum bay-create --name k8sbay --baymodel k8sbaymodel --node-count 1
|
|
|
|
|
|
3. Configure kubelet.
|
|
|
|
To allow Kubernetes to interface with Cinder, log into each minion
|
|
node of your bay and perform step 4 through 6::
|
|
|
|
sudo vi /etc/kubernetes/kubelet
|
|
|
|
Comment out the line::
|
|
|
|
#KUBELET_ARGS=--config=/etc/kubernetes/manifests --cadvisor-port=4194
|
|
|
|
Uncomment the line::
|
|
|
|
#KUBELET_ARGS="--config=/etc/kubernetes/manifests --cadvisor-port=4194 --cloud-provider=openstack --cloud-config=/etc/kubernetes/kube_openstack_config"
|
|
|
|
|
|
4. Enter OpenStack user credential::
|
|
|
|
sudo vi /etc/kubernetes/kube_openstack_config
|
|
|
|
The username, tenant-name and region entries have been filled in with the
|
|
Keystone values of the user who created the bay. Enter the password
|
|
of this user on the entry for password::
|
|
|
|
password=ChangeMe
|
|
|
|
5. Restart Kubernetes services::
|
|
|
|
sudo systemctl restart kubelet
|
|
|
|
On restart, the new configuration enables the Kubernetes cloud provider
|
|
plugin for OpenStack, along with the necessary credential for kubelet
|
|
to authenticate with Keystone and to make request to OpenStack services.
|
|
|
|
6. Install nsenter::
|
|
|
|
sudo docker run -v /usr/local/bin:/target jpetazzo/nsenter
|
|
|
|
The nsenter utility is used by Kubernetes to run new processes within
|
|
existing kernel namespaces. This allows the kubelet agent to manage storage
|
|
for pods.
|
|
|
|
Kubernetes is now ready to use Cinder for persistent storage.
|
|
Following is an example illustrating how Cinder is used in a pod.
|
|
|
|
1. Create the cinder volume::
|
|
|
|
cinder create --display-name=test-repo 1
|
|
|
|
ID=$(cinder create --display-name=test-repo 1 | awk -F'|' '$2~/^[[:space:]]*id/ {print $3}')
|
|
|
|
The command will generate the volume with a ID. The volume ID will be specified in
|
|
Step 2.
|
|
|
|
2. Create a pod in this bay and mount this cinder volume to the pod.
|
|
Create a file (e.g nginx-cinder.yaml) describing the pod::
|
|
|
|
cat > nginx-cinder.yaml << END
|
|
apiVersion: v1
|
|
kind: Pod
|
|
metadata:
|
|
name: aws-web
|
|
spec:
|
|
containers:
|
|
- name: web
|
|
image: nginx
|
|
ports:
|
|
- name: web
|
|
containerPort: 80
|
|
hostPort: 8081
|
|
protocol: TCP
|
|
volumeMounts:
|
|
- name: html-volume
|
|
mountPath: "/usr/share/nginx/html"
|
|
volumes:
|
|
- name: html-volume
|
|
cinder:
|
|
# Enter the volume ID below
|
|
volumeID: $ID
|
|
fsType: ext4
|
|
END
|
|
|
|
**NOTE:** The Cinder volume ID needs to be configured in the yaml file
|
|
so the existing Cinder volume can be mounted in a pod by specifying
|
|
the volume ID in the pod manifest as follows::
|
|
|
|
volumes:
|
|
- name: html-volume
|
|
cinder:
|
|
volumeID: $ID
|
|
fsType: ext4
|
|
|
|
3. Create the pod by the normal Kubernetes interface::
|
|
|
|
kubectl create -f nginx-cinder.yaml
|
|
|
|
You can start a shell in the container to check that the mountPath exists,
|
|
and on an OpenStack client you can run the command 'cinder list' to verify
|
|
that the cinder volume status is 'in-use'.
|
|
|
|
|
|
Using Cinder in Swarm
|
|
+++++++++++++++++++++
|
|
*To be filled in*
|
|
|
|
|
|
Using Cinder in Mesos
|
|
+++++++++++++++++++++
|
|
|
|
1. Create the baymodel.
|
|
|
|
Specify 'rexray' as the volume-driver for Mesos. As an option, you
|
|
can specify in a label the attributes 'rexray_preempt' to enable
|
|
any host to take control of a volume regardless if other
|
|
hosts are using the volume. If this is set to false, the driver
|
|
will ensure data safety by locking the volume::
|
|
|
|
magnum baymodel-create --name mesosbaymodel \
|
|
--image-id ubuntu-mesos \
|
|
--keypair-id testkey \
|
|
--external-network-id public \
|
|
--dns-nameserver 8.8.8.8 \
|
|
--master-flavor-id m1.magnum \
|
|
--docker-volume-size 4 \
|
|
--tls-disabled \
|
|
--flavor-id m1.magnum \
|
|
--coe mesos \
|
|
--volume-driver rexray \
|
|
--labels rexray-preempt=true
|
|
|
|
2. Create the Mesos bay::
|
|
|
|
magnum bay-create --name mesosbay --baymodel mesosbaymodel --node-count 1
|
|
|
|
3. Create the cinder volume and configure this bay::
|
|
|
|
cinder create --display-name=redisdata 1
|
|
|
|
Create the following file ::
|
|
|
|
cat > mesos.json << END
|
|
{
|
|
"id": "redis",
|
|
"container": {
|
|
"docker": {
|
|
"image": "redis",
|
|
"network": "BRIDGE",
|
|
"portMappings": [
|
|
{ "containerPort": 80, "hostPort": 0, "protocol": "tcp"}
|
|
],
|
|
"parameters": [
|
|
{ "key": "volume-driver", "value": "rexray" },
|
|
{ "key": "volume", "value": "redisdata:/data" }
|
|
]
|
|
}
|
|
},
|
|
"cpus": 0.2,
|
|
"mem": 32.0,
|
|
"instances": 1
|
|
}
|
|
END
|
|
|
|
**NOTE:** When the Mesos bay is created using this baymodel, the Mesos bay
|
|
will be configured so that a filesystem on an existing cinder volume can
|
|
be mounted in a container by configuring the parameters to mount the cinder
|
|
volume in the json file ::
|
|
|
|
"parameters": [
|
|
{ "key": "volume-driver", "value": "rexray" },
|
|
{ "key": "volume", "value": "redisdata:/data" }
|
|
]
|
|
|
|
4. Create the container using Marathon REST API ::
|
|
|
|
MASTER_IP=$(magnum bay-show mesosbay | awk '/ api_address /{print $4}')
|
|
curl -X POST -H "Content-Type: application/json" \
|
|
http://${MASTER_IP}:8080/v2/apps -d@mesos.json
|
|
|
|
You can log into the container to check that the mountPath exists, and
|
|
you can run the command 'cinder list' to verify that your cinder
|
|
volume status is 'in-use'.
|
|
|
|
|
|
================
|
|
Image Management
|
|
================
|
|
|
|
When a COE is deployed, an image from Glance is used to boot the nodes
|
|
in the cluster and then the software will be configured and started on
|
|
the nodes to bring up the full cluster. An image is based on a
|
|
particular distro such as Fedora, Ubuntu, etc, and is prebuilt with
|
|
the software specific to the COE such as Kubernetes, Swarm, Mesos.
|
|
The image is tightly coupled with the following in Magnum:
|
|
|
|
1. Heat templates to orchestrate the configuration.
|
|
|
|
2. Template definition to map baymodel parameters to Heat
|
|
template parameters.
|
|
|
|
3. Set of scripts to configure software.
|
|
|
|
Collectively, they constitute the driver for a particular COE and a
|
|
particular distro; therefore, developing a new image needs to be done
|
|
in conjunction with developing these other components. Image can be
|
|
built by various methods such as diskimagebuilder, or in some case, a
|
|
distro image can be used directly. A number of drivers and the
|
|
associated images is supported in Magnum as reference implementation.
|
|
In this section, we focus mainly on the supported images.
|
|
|
|
All images must include support for cloud-init and the heat software
|
|
configuration utility:
|
|
|
|
- os-collect-config
|
|
- os-refresh-config
|
|
- os-apply-config
|
|
- heat-config
|
|
- heat-config-script
|
|
|
|
Additional software are described as follows.
|
|
|
|
Kubernetes on Fedora Atomic
|
|
---------------------------
|
|
|
|
This image can be downloaded from the `public Atomic site
|
|
<https://alt.fedoraproject.org/pub/alt/atomic/stable/Cloud-Images/x86_64/Images/>`_
|
|
or can be built locally using diskimagebuilder. Details can be found in the
|
|
`fedora-atomic element
|
|
<https://github.com/openstack/magnum/tree/master/magnum/elements/fedora-atomic>`_
|
|
The image currently has the following OS/software:
|
|
|
|
+-------------+-----------+
|
|
| OS/software | version |
|
|
+=============+===========+
|
|
| Fedora | 23 |
|
|
+-------------+-----------+
|
|
| Docker | 1.9.1 |
|
|
+-------------+-----------+
|
|
| Kubernetes | 1.2.0 |
|
|
+-------------+-----------+
|
|
| etcd | 2.2.1 |
|
|
+-------------+-----------+
|
|
| Flannel | 0.5.4 |
|
|
+-------------+-----------+
|
|
|
|
The following software are managed as systemd services:
|
|
|
|
- kube-apiserver
|
|
- kubelet
|
|
- etcd
|
|
- flannel (if specified as network driver)
|
|
- docker
|
|
|
|
The following software are managed as Docker containers:
|
|
|
|
- kube-controller-manager
|
|
- kube-scheduler
|
|
- kube-proxy
|
|
|
|
The login for this image is *minion*.
|
|
|
|
Kubernetes on CoreOS
|
|
--------------------
|
|
|
|
CoreOS publishes a `stock image
|
|
<http://beta.release.core-os.net/amd64-usr/current/coreos_production_openstack_image.img.bz2>`_
|
|
that is being used to deploy Kubernetes.
|
|
This image has the following OS/software:
|
|
|
|
+-------------+-----------+
|
|
| OS/software | version |
|
|
+=============+===========+
|
|
| CoreOS | 4.3.6 |
|
|
+-------------+-----------+
|
|
| Docker | 1.9.1 |
|
|
+-------------+-----------+
|
|
| Kubernetes | 1.0.6 |
|
|
+-------------+-----------+
|
|
| etcd | 2.2.3 |
|
|
+-------------+-----------+
|
|
| Flannel | 0.5.5 |
|
|
+-------------+-----------+
|
|
|
|
The following software are managed as systemd services:
|
|
|
|
- kubelet
|
|
- flannel (if specified as network driver)
|
|
- docker
|
|
- etcd
|
|
|
|
The following software are managed as Docker containers:
|
|
|
|
- kube-apiserver
|
|
- kube-controller-manager
|
|
- kube-scheduler
|
|
- kube-proxy
|
|
|
|
The login for this image is *core*.
|
|
|
|
Kubernetes on Ironic
|
|
--------------------
|
|
|
|
This image is built manually using diskimagebuilder. The scripts and instructions
|
|
are included in `Magnum code repo
|
|
<https://github.com/openstack/magnum/tree/master/magnum/templates/kubernetes/elements>`_.
|
|
Currently Ironic is not fully supported yet, therefore more details will be
|
|
provided when this driver has been fully tested.
|
|
|
|
|
|
Swarm on Fedora Atomic
|
|
----------------------
|
|
|
|
This image is the same as the image for `Kubernetes on Fedora Atomic`_
|
|
described above. The login for this image is *fedora*.
|
|
|
|
Mesos on Ubuntu
|
|
---------------
|
|
|
|
This image is built manually using diskimagebuilder. The instructions are
|
|
provided in this `Mesos guide
|
|
<https://github.com/openstack/magnum/blob/master/doc/source/dev/mesos.rst>`_.
|
|
The Fedora site hosts the current image `ubuntu-14.04.3-mesos-0.25.0.qcow2
|
|
<https://fedorapeople.org/groups/magnum/ubuntu-14.04.3-mesos-0.25.0.qcow2>`_.
|
|
|
|
+-------------+-----------+
|
|
| OS/software | version |
|
|
+=============+===========+
|
|
| Ubuntu | 14.04 |
|
|
+-------------+-----------+
|
|
| Docker | 1.8.1 |
|
|
+-------------+-----------+
|
|
| Mesos | 0.25.0 |
|
|
+-------------+-----------+
|
|
| Marathon | 0.11.1 |
|
|
+-------------+-----------+
|
|
|
|
============
|
|
Notification
|
|
============
|
|
|
|
Magnum provides notifications about usage data so that 3rd party applications
|
|
can use the data for auditing, billing, monitoring, or quota purposes. This
|
|
document describes the current inclusions and exclusions for Magnum
|
|
notifications.
|
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Magnum uses Cloud Auditing Data Federation (`CADF`_) Notification as its
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notification format for better support of auditing, details about CADF are
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documented below.
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Auditing with CADF
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------------------
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Magnum uses the `PyCADF`_ library to emit CADF notifications, these events
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adhere to the DMTF `CADF`_ specification. This standard provides auditing
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capabilities for compliance with security, operational, and business processes
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and supports normalized and categorized event data for federation and
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aggregation.
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.. _PyCADF: http://docs.openstack.org/developer/pycadf
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.. _CADF: http://www.dmtf.org/standards/cadf
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Below table describes the event model components and semantics for
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each component:
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+-----------------+----------------------------------------------------------+
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| model component | CADF Definition |
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+=================+==========================================================+
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| OBSERVER | The RESOURCE that generates the CADF Event Record based |
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| | on its observation (directly or indirectly) of the |
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| | Actual Event. |
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+-----------------+----------------------------------------------------------+
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| INITIATOR | The RESOURCE that initiated, originated, or instigated |
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| | the event's ACTION, according to the OBSERVER. |
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+-----------------+----------------------------------------------------------+
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| ACTION | The operation or activity the INITIATOR has performed, |
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| | has attempted to perform or has pending against the |
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| | event's TARGET, according to the OBSERVER. |
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+-----------------+----------------------------------------------------------+
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| TARGET | The RESOURCE against which the ACTION of a CADF Event |
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| | Record was performed, attempted, or is pending, |
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| | according to the OBSERVER. |
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+-----------------+----------------------------------------------------------+
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| OUTCOME | The result or status of the ACTION against the TARGET, |
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| | according to the OBSERVER. |
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+-----------------+----------------------------------------------------------+
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The ``payload`` portion of a CADF Notification is a CADF ``event``, which
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is represented as a JSON dictionary. For example:
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.. code-block:: javascript
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{
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"typeURI": "http://schemas.dmtf.org/cloud/audit/1.0/event",
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"initiator": {
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"typeURI": "service/security/account/user",
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"host": {
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"agent": "curl/7.22.0(x86_64-pc-linux-gnu)",
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"address": "127.0.0.1"
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},
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"id": "<initiator_id>"
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},
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"target": {
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"typeURI": "<target_uri>",
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"id": "openstack:1c2fc591-facb-4479-a327-520dade1ea15"
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},
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"observer": {
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"typeURI": "service/security",
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"id": "openstack:3d4a50a9-2b59-438b-bf19-c231f9c7625a"
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},
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"eventType": "activity",
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"eventTime": "2014-02-14T01:20:47.932842+00:00",
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"action": "<action>",
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"outcome": "success",
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"id": "openstack:f5352d7b-bee6-4c22-8213-450e7b646e9f",
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}
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Where the following are defined:
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* ``<initiator_id>``: ID of the user that performed the operation
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* ``<target_uri>``: CADF specific target URI, (i.e.: data/security/project)
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* ``<action>``: The action being performed, typically:
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``<operation>``. ``<resource_type>``
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Additionally there may be extra keys present depending on the operation being
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performed, these will be discussed below.
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Note, the ``eventType`` property of the CADF payload is different from the
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``event_type`` property of a notifications. The former (``eventType``) is a
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CADF keyword which designates the type of event that is being measured, this
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can be: `activity`, `monitor` or `control`. Whereas the latter
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(``event_type``) is described in previous sections as:
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`magnum.<resource_type>.<operation>`
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Supported Events
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----------------
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The following table displays the corresponding relationship between resource
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types and operations.
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+---------------+----------------------------+-------------------------+
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| resource type | supported operations | typeURI |
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+===============+============================+=========================+
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| bay | create, update, delete | service/magnum/bay |
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+---------------+----------------------------+-------------------------+
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Example Notification - Bay Create
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---------------------------------
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The following is an example of a notification that is sent when a bay is
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created. This example can be applied for any ``create``, ``update`` or
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``delete`` event that is seen in the table above. The ``<action>`` and
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``typeURI`` fields will be change.
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.. code-block:: javascript
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{
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"event_type": "magnum.bay.created",
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"message_id": "0156ee79-b35f-4cef-ac37-d4a85f231c69",
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"payload": {
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"typeURI": "http://schemas.dmtf.org/cloud/audit/1.0/event",
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"initiator": {
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"typeURI": "service/security/account/user",
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"id": "c9f76d3c31e142af9291de2935bde98a",
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"user_id": "0156ee79-b35f-4cef-ac37-d4a85f231c69",
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"project_id": "3d4a50a9-2b59-438b-bf19-c231f9c7625a"
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},
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"target": {
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"typeURI": "service/magnum/bay",
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"id": "openstack:1c2fc591-facb-4479-a327-520dade1ea15"
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},
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"observer": {
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"typeURI": "service/magnum/bay",
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"id": "openstack:3d4a50a9-2b59-438b-bf19-c231f9c7625a"
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},
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"eventType": "activity",
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"eventTime": "2015-05-20T01:20:47.932842+00:00",
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"action": "create",
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"outcome": "success",
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"id": "openstack:f5352d7b-bee6-4c22-8213-450e7b646e9f",
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"resource_info": "671da331c47d4e29bb6ea1d270154ec3"
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}
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"priority": "INFO",
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"publisher_id": "magnum.host1234",
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"timestamp": "2016-05-20 15:03:45.960280"
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}
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