Add docs on host configuration

Change-Id: I2962d148afb77834f78deedf206060b86445055a
Story: 2004337
Task: 27924
This commit is contained in:
Mark Goddard 2018-11-27 18:57:47 +00:00
parent bf3d31aaa2
commit b9ae3e2290
7 changed files with 614 additions and 25 deletions

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@ -28,6 +28,6 @@ virtualenv_path: "{{ base_path ~ '/venvs' }}"
###############################################################################
# User configuration.
# User with which to access seed and controller nodes. This user will be
# created if it does not exist.
# User with which to access remote hosts. This user will be created if it does
# not exist.
kayobe_ansible_user: "stack"

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@ -0,0 +1,565 @@
==================
Host Configuration
==================
This section covers configuration of hosts. It does not cover configuration or
deployment of containers. Hosts that are configured by Kayobe include:
* Seed hypervisor (``kayobe seed hypervisor host configure``)
* Seed (``kayobe seed host configure``)
* Overcloud (``kayobe overcloud host configure``)
Unless otherwise stated, all host configuration described here is applied to
each of these types of host.
Configuration Location
======================
Some host configuration options are set via global variables, and others have a
variable for each type of host. The latter variables are included in the
following files under ``${KAYOBE_CONFIG_PATH}``:
* ``seed-hypervisor.yml``
* ``seed.yml``
* ``compute.yml``
* ``controller.yml``
* ``monitoring.yml``
* ``storage.yml``
Note that any variable may be set on a per-host or per-group basis, by using
inventory host or group variables - these delineations are for convenience.
Paths
=====
Several directories are used by Kayobe on the remote hosts. There is a
hierarchy of variables in ``${KAYOBE_CONFIG_PATH}/globals.yml`` that can be
used to control where these are located.
* ``base_path`` (default ``/opt/kayobe/``) sets the default base path for
various directories.
* ``config_path`` (default ``{{ base_path }}/etc``) is a path in which to store
configuration files.
* ``image_cache_path`` (default ``{{ base_path }}/images``) is a path in which
to cache downloaded or built images.
* ``source_checkout_path`` (default ``{{ base_path }}/src``) is a path into
which to store clones of source code repositories.
* ``virtualenv_path`` (default ``{{ base_path }}/venvs``) is a path in which to
create Python virtual environments.
SSH Known Hosts
===============
While strictly this configuration is applied to the Ansible control host
(``localhost``), it is applied during the ``host configure`` commands.
The ``ansible_host`` of each host is added as an SSH known host. This is
typically the host's IP address on the admin network (``admin_oc_net_name``),
as defined in ``${KAYOBE_CONFIG_PATH}/network-allocation.yml`` (see
:ref:`configuration-network-ip-allocation`).
Kayobe User Bootstrapping
=========================
Kayobe uses a user account defined by the ``kayobe_ansible_user`` variable (in
``${KAYOBE_CONFIG_PATH}/globals.yml``) for remote SSH access. By default, this
is ``stack``.
Typically, the image used to provision these hosts will not include this user
account, so Kayobe performs a bootstrapping step to create it, as a different
user. In cloud images, there is often a user named after the OS distro, e.g.
``centos`` or ``ubuntu``. This user defaults to the name of the user running
Kayobe, but may be set via the following variables:
* ``seed_hypervisor_bootstrap_user``
* ``seed_bootstrap_user``
* ``compute_bootstrap_user``
* ``controller_bootstrap_user``
* ``monitoring_bootstrap_user``
* ``storage_bootstrap_user``
For example, to set the bootstrap user for controllers to ``centos``:
.. code-block:: yaml
:caption: ``controllers.yml``
controller_bootstrap_user: centos
PyPI Mirror
===========
Kayobe supports configuration of a PyPI mirror, via variables in
``${KAYOBE_CONFIG_PATH}/pip.yml``. This functionality is enabled by setting the
``pip_local_mirror`` variable to ``true``.
Kayobe will generate configuration for
``pip`` and ``easy_install`` to use the mirror, for the list of users defined
by ``pip_applicable_users`` (default ``kayobe_ansible_user`` and ``root``), in
addition to the user used for Kolla Ansible (``kolla_ansible_user``). The
mirror URL is configured via ``pip_index_url``, and ``pip_trusted_hosts`` is a
list of 'trusted' hosts, for which SSL verification will be disabled.
For example, to configure use of the test PyPI mirror at
https://test.pypi.org/simple/:
.. code-block:: yaml
:caption: ``pip.yml``
pip_local_mirror: true
pip_index_url: https://test.pypi.org/simple/
Kayobe Remote Virtual Environment
=================================
By default, Ansible executes modules remotely using the system python
interpreter, even if the Ansible control process is executed from within a
virtual environment (unless the ``local`` connection plugin is used).
This is not ideal if there are python dependencies that must be installed
with isolation from the system python packages. Ansible can be configured to
use a virtualenv by setting the host variable ``ansible_python_interpreter``
to a path to a python interpreter in an existing virtual environment.
If kayobe detects that ``ansible_python_interpreter`` is set and references a
virtual environment, it will create the virtual environment if it does not
exist. Typically this variable should be set via a group variable in the
inventory for hosts in the ``seed``, ``seed-hypervisor``, and/or ``overcloud``
groups.
The default Kayobe configuration in the ``kayobe-config`` repository sets
``ansible_python_interpreter`` to ``{{ virtualenv_path }}/kayobe/bin/python``
for the ``seed``, ``seed-hypervisor``, and ``overcloud`` groups.
Disk Wiping
===========
Using hosts that may have stale data on their disks could affect the deployment
of the cloud. This is not a configuration option, since it should only be
performed once to avoid losing useful data. It is triggered by passing the
``--wipe-disks`` argument to the ``host configure`` commands.
Users and Groups
================
Linux user accounts and groups can be configured using the ``users_default``
variable in ``${KAYOBE_CONFIG_PATH}/users.yml``. The format of the list is
that used by the ``users`` variable of the `singleplatform-eng.users
<https://galaxy.ansible.com/singleplatform-eng/users>`__ role. The following
variables can be used to set the users for specific types of hosts:
* ``seed_hypervisor_users``
* ``seed_users``
* ``compute_users``
* ``controller_users``
* ``monitoring_users``
* ``storage_users``
In the following example, a single user named ``bob`` is created. A password
hash has been generated via ``mkpasswd --method=sha-512``. The user is added to
the ``wheel`` group, and an SSH key is authorised. The SSH public key should be
added to the Kayobe configuration.
.. code-block:: yaml
:caption: ``users.yml``
users_default:
- username: bob
name: Bob
password: "$6$wJt9MLWrHlWN8$oXJHbdaslm9guD5EC3Dry1mphuqF9NPeQ43OXk3cXZa2ze/F9FOTxm2KvvDkbdxBDs7ouwdiLTUJ1Ff40.cFU."
groups:
- wheel
append: True
ssh_key:
- "{{ lookup('file', kayobe_config_path ~ '/ssh-keys/id_rsa_bob.pub') }}"
Package Repositories
====================
Kayobe supports configuration of package repositories via Yum, via variables in
``${KAYOBE_CONFIG_PATH}/yum.yml``.
CentOS and EPEL Mirrors
-----------------------
CentOS and EPEL mirrors can be enabled by setting ``yum_use_local_mirror`` to
``true``. CentOS repository mirrors are configured via the following
variables:
* ``yum_centos_mirror_host`` (default ``mirror.centos.org``) is the mirror
hostname.
* ``yum_centos_mirror_directory`` (default ``centos``) is a directory on the
mirror in which repositories may be accessed.
EPEL repository mirrors are configured via the following variables:
* ``yum_epel_mirror_host`` (default ``download.fedoraproject.org``) is the
mirror hostname.
* ``yum_epel_mirror_directory`` (default ``pub/epel``) is a directory on the
mirror in which repositories may be accessed.
For example, to configure CentOS and EPEL mirrors at mirror.example.com:
.. code-block:: yaml
:caption: ``yum.yml``
yum_use_local_mirror: true
yum_centos_mirror_host: mirror.example.com
yum_epel_mirror_host: mirror.example.com
Custom Yum Repositories
-----------------------
It is also possible to configure a list of custom Yum repositories via the
``yum_custom_repos`` variable. The format is a dict/map, with repository names
mapping to a dict/map of arguments to pass to the Ansible ``yum`` module.
For example, the following configuration defines a single Yum repository called
``widgets``.
.. code-block:: yaml
:caption: ``yum.yml``
yum_custom_repos:
widgets:
baseurl: http://example.com/repo
file: widgets
gpgkey: http://example.com/gpgkey
gpgcheck: yes
Disabling EPEL
--------------
It is possible to disable the EPEL Yum repository by setting
``yum_install_epel`` to ``false``.
SELinux
=======
SELinux is not supported by Kolla Ansible currently, so it is disabled by
Kayobe. If necessary, Kayobe will reboot systems in order to apply a change to
the SELinux configuration. The timeout for waiting for systems to reboot is
``disable_selinux_reboot_timeout``. Alternatively, the reboot may be avoided by
setting ``disable_selinux_do_reboot`` to ``false``.
Network Configuration
=====================
Configuration of host networking is covered in depth in
:ref:`configuration-network`.
Sysctls
=======
Arbitrary ``sysctl`` configuration can be applied to hosts. The variable format
is a dict/map, mapping parameter names to their required values. The following
variables can be used to set ``sysctl`` configuration specific types of hosts:
* ``seed_hypervisor_sysctl_parameters``
* ``seed_sysctl_parameters``
* ``compute_sysctl_parameters``
* ``controller_sysctl_parameters``
* ``monitoring_sysctl_parameters``
* ``storage_sysctl_parameters``
For example, to set the ``net.ipv4.ip_forward`` parameter to ``1`` on controllers:
.. code-block:: yaml
:caption: ``controllers.yml``
controller_sysctl_parameters:
net.ipv4.ip_forward: 1
Disable cloud-init
==================
cloud-init is a popular service for performing system bootstrapping. If you are
not using cloud-init, this section can be skipped.
If using the seed's Bifrost service to provision the control plane hosts, the
use of cloud-init may be configured via the ``kolla_bifrost_dib_init_element``
variable.
cloud-init searches for network configuration in order of increasing
precedence; each item overriding the previous. In some cases, on subsequent
boots cloud-init can automatically reconfigure network interfaces and cause
some issues in network configuration. To disable cloud-init from running after
the initial server bootstrapping, set ``disable_cloud_init`` to ``true`` in
``${KAYOBE_CONFIG_PATH}/overcloud.yml``.
Disable Glean
=============
The ``glean`` service can be used to perform system bootstrapping, serving a
similar role to ``cloud-init``. If you are not using ``glean``, this section
can be skipped.
If using the seed's Bifrost service to provision the control plane hosts, the
use of ``glean`` may be configured via the ``kolla_bifrost_dib_init_element``
variable.
After the initial server bootstrapping, the glean service can cause problems as
it attempts to enable all network interfaces, which can lead to timeouts while
booting. To avoid this, the ``glean`` service is disabled. Additionally, any
network interface configuration files generated by ``glean`` and not
overwritten by Kayobe are removed.
Timezone
========
The timezone can be configured via the ``timezone`` variable in
``${KAYOBE_CONFIG_PATH}/ntp.yml``. The value must be a valid Linux
timezone. For example:
.. code-block:: yaml
:caption: ``ntp.yml``
timezone: Europe/London
NTP
===
Network Time Protocol (NTP) may be configured via variables in
``${KAYOBE_CONFIG_PATH}/ntp.yml``. The list of NTP servers is
configured via ``ntp_config_server``, and by default the ``pool.ntp.org``
servers are used. A list of restrictions may be added via
``ntp_config_restrict``, and a list of interfaces to listen on via
``ntp_config_listen``. Other options and their default values may be found in
the `resmo.ntp <https://galaxy.ansible.com/resmo/ntp>`__ Ansible role.
.. code-block:: yaml
:caption: ``ntp.yml``
ntp_config_server:
- 1.ubuntu.pool.ntp.org
- 2.ubuntu.pool.ntp.org
ntp_config_restrict:
- '-4 default kod notrap nomodify nopeer noquery'
ntp_config_listen:
- eth0
The NTP service may be disabled as follows:
.. code-block:: yaml
:caption: ``ntp.yml``
ntp_package_state: absent
ntp_service_state: stopped
ntp_service_enabled: false
.. _configuration-hosts-lvm:
LVM
===
Logical Volume Manager (LVM) physical volumes, volume groups, and logical
volumes may be configured via the ``lvm_groups`` variable. For convenience,
this is mapped to the following variables:
* ``seed_lvm_groups``
* ``compute_lvm_groups``
* ``controller_lvm_groups``
* ``monitoring_lvm_groups``
* ``storage_lvm_groups``
Note that LVM is not configured on the seed hypervisor.
The format of these variables is as defined by the ``lvm_groups`` variable of
the `mrlesmithjr.manage-lvm
<https://galaxy.ansible.com/mrlesmithjr/manage-lvm>`__ Ansible role.
LVM for Docker
--------------
The default LVM configuration is optimised for the ``devicemapper`` Docker
storage driver, which requires a thin provisioned LVM volume. A second logical
volume is used for storing Docker volume data, mounted at
``/var/lib/docker/volumes``. Both logical volumes are created from a single
``data`` volume group.
To use this configuration, a list of disks must be configured via the following
variables:
* ``seed_lvm_group_data_disks``
* ``compute_lvm_group_data_disks``
* ``controller_lvm_group_data_disks``
* ``monitoring_lvm_group_data_disks``
* ``storage_lvm_group_data_disks``
For example, to configure two of the seed's disks for use by LVM:
.. code-block:: yaml
:caption: ``seed.yml``
seed_lvm_group_data_disks:
- /dev/sdb
- /dev/sdc
The Docker volumes LVM volume is assigned a size given by the following
variables, with a default value of 75% (of the volume group's capacity):
* ``seed_lvm_group_data_lv_docker_volumes_size``
* ``compute_lvm_group_data_lv_docker_volumes_size``
* ``controller_lvm_group_data_lv_docker_volumes_size``
* ``monitoring_lvm_group_data_lv_docker_volumes_size``
* ``storage_lvm_group_data_lv_docker_volumes_size``
If using a Docker storage driver other than ``devicemapper``, the remaining 25%
of the volume group can be used for Docker volume data. In this case, the LVM
volume's size can be increased to 100%:
.. code-block:: yaml
:caption: ``controllers.yml``
controller_lvm_group_data_lv_docker_volumes_size: 100%
If using a Docker storage driver other than ``devicemapper``, it is possible to
avoid using LVM entirely, thus avoiding the requirement for multiple disks. In
this case, set the appropriate ``<host>_lvm_groups`` variable to an empty list:
.. code-block:: yaml
:caption: ``storage.yml``
storage_lvm_groups: []
Custom LVM
----------
To define additional logical logical volumes in the default ``data`` volume
group, modify one of the following variables:
* ``seed_lvm_group_data_lvs``
* ``compute_lvm_group_data_lvs``
* ``controller_lvm_group_data_lvs``
* ``monitoring_lvm_group_data_lvs``
* ``storage_lvm_group_data_lvs``
Include the variable ``<host>_lvm_group_data_lv_docker_volumes`` in the list to
include the LVM volume for Docker volume data:
.. code-block:: yaml
:caption: ``monitoring.yml``
monitoring_lvm_group_data_lvs:
- "{{ monitoring_lvm_group_data_lv_docker_volumes }}"
- lvname: other-vol
size: 1%
create: true
filesystem: ext4
mount: true
mntp: /path/to/mount
It is possible to define additional LVM volume groups via the following
variables:
* ``seed_lvm_groups_extra``
* ``compute_lvm_groups_extra``
* ``controller_lvm_groups_extra``
* ``monitoring_lvm_groups_extra``
* ``storage_lvm_groups_extra``
For example:
.. code-block:: yaml
:caption: ``compute.yml``
compute_lvm_groups_extra:
- vgname: other-vg
disks: /dev/sdb
create: true
lvnames:
- lvname: other-vol
size: 100%
create: true
mount: false
Alternatively, replace the entire volume group list via one of the
``<host>_lvm_groups`` variables to replace the default configuration with a
custom one.
.. code-block:: yaml
:caption: ``controllers.yml``
controller_lvm_groups:
- vgname: only-vg
disks: /dev/sdb
create: true
lvnames:
- lvname: only-vol
size: 100%
create: true
mount: false
Kolla-ansible bootstrap-servers
===============================
Kolla Ansible provides some host configuration functionality via the
``bootstrap-servers`` command, which may be leveraged by Kayobe. Due to the
bootstrapping nature of the command, Kayobe uses ``kayobe_ansible_user`` to
execute it, and uses the Kayobe remote Python virtual environment (or the
system Python interpreter if no virtual environment is in use).
See the `Kolla Ansible documentation
<https://docs.openstack.org/kolla-ansible/latest/reference/deployment-and-bootstrapping/bootstrap-servers.html>`__
for more information on the functions performed by this command, and how to
configure it.
Kolla-ansible Remote Virtual Environment
========================================
See :ref:`configuration-kolla-ansible-venv` for information about remote Python
virtual environments for Kolla Ansible.
Docker Engine
=============
Docker engine configuration is applied by both Kayobe and Kolla Ansible (during
bootstrap-servers).
The ``docker_storage_driver`` variable sets the Docker storage driver, and by
default the ``devicemapper`` driver is used. If using this driver, see
:ref:`configuration-hosts-lvm` for information about configuring LVM for
Docker.
Various options are defined in ``${KAYOBE_CONFIG_PATH}/docker.yml``
for configuring the ``devicemapper`` storage.
A private Docker registry may be configured via ``docker_registry``, with a
Certificate Authority (CA) file configured via ``docker_registry_ca``.
To use one or more Docker Registry mirrors, use the ``docker_registry_mirrors``
variable.
If using an MTU other than 1500, ``docker_daemon_mtu`` can be used to configure
this. This setting does not apply to containers using ``net=host`` (as Kolla
Ansible's containers do), but may be necessary when building images.
Docker's live restore feature can be configured via
``docker_daemon_live_restore``, although it is disabled by default due to
issues observed.
Ceph Block Devices
==================
If using Kolla Ansible to deploy Ceph, some preparation of block devices is
required. The list of disks to configure for use by Ceph is specified via
``ceph_disks``. This is mapped to the following variables:
* ``compute_ceph_disks``
* ``controller_ceph_disks``
* ``storage_ceph_disks``
The format of the variable is a list of dict/mapping objects. Each mapping
should contain an ``osd`` item that defines the full path to a block device to
use for data. Optionally, each mapping may contain a ``journal`` item that
specifies the full path to a block device to use for journal data.
The following example defines two OSDs for use by controllers, one of which has
a journal:
.. code-block:: yaml
:caption: ``controller.yml``
controller_ceph_disks:
- osd: /dev/sdb
- osd: /dev/sdc
journal: /dev/sdd

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@ -8,4 +8,5 @@ Configuration Guide
kayobe
physical-network
network
hosts
kolla-ansible

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@ -116,23 +116,3 @@ configuration files may be encrypted. Since encryption can make working with
Kayobe difficult, it is recommended to follow `best practice
<http://docs.ansible.com/ansible/playbooks_best_practices.html#best-practices-for-variables-and-vaults>`_,
adding a layer of indirection and using encryption only where necessary.
Remote Execution Environment
----------------------------
By default, ansible executes modules remotely using the system python
interpreter, even if the ansible control process is executed from within a
virtual environment (unless the ``local`` connection plugin is used).
This is not ideal if there are python dependencies that must be installed
without isolation from the system python packages. Ansible can be configured to
use a virtualenv by setting the host variable ``ansible_python_interpreter``
to a path to a python interpreter in an existing virtual environment.
If kayobe detects that ``ansible_python_interpreter`` is set and references a
virtual environment, it will create the virtual environment if it does not
exist. Typically this variable should be set via a group variable for hosts in
the ``seed``, ``seed-hypervisor``, and/or ``overcloud`` groups.
The default Kayobe configuration in the ``kayobe-config`` repository sets
``ansible_python_interpreter`` to ``{{ virtualenv_path }}/kayobe/bin/python``
for the ``seed``, ``seed-hypervisor``, and ``overcloud`` groups.

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@ -43,6 +43,8 @@ lookup plugin
kolla_ansible_venv_extra_requirements:
- "hvac"
.. _configuration-kolla-ansible-venv:
Remote Execution Environment
============================
@ -50,7 +52,7 @@ By default, ansible executes modules remotely using the system python
interpreter, even if the ansible control process is executed from within a
virtual environment (unless the ``local`` connection plugin is used).
This is not ideal if there are python dependencies that must be installed
without isolation from the system python packages. Ansible can be configured to
with isolation from the system python packages. Ansible can be configured to
use a virtualenv by setting the host variable ``ansible_python_interpreter``
to a path to a python interpreter in an existing virtual environment.

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@ -1,3 +1,5 @@
.. _configuration-network:
=====================
Network Configuration
=====================
@ -39,6 +41,10 @@ supported:
VLAN ID.
``mtu``
Maximum Transmission Unit (MTU).
``vip_address``
Virtual IP address (VIP) used by API services on this network.
``fqdn``
Fully Qualified Domain Name (FQDN) used by API services on this network.
``routes``
List of static IP routes. Each item should be a dict containing the
item ``cidr``, and optionally ``gateway`` and ``table``. ``cidr`` is the CIDR
@ -85,6 +91,36 @@ This gateway will be configured on all hosts to which the network is mapped.
Note that configuring multiple IP gateways on a single host will lead to
unpredictable results.
Configuring an API Virtual IP Address
-------------------------------------
A virtual IP (VIP) address may be configured for use by Kolla Ansible on the
internal and external networks, on which the API services will be exposed.
The variable will be passed through to the ``kolla_internal_vip_address`` or
``kolla_external_vip_address`` Kolla Ansible variable.
To configure a network called ``example`` with a VIP at ``10.0.0.2``:
.. code-block:: yaml
:caption: ``networks.yml``
example_vip_address: 10.0.0.2
Configuring an API Fully Qualified Domain Name
----------------------------------------------
A Fully Qualified Domain Name (FQDN) may be configured for use by Kolla Ansible
on the internal and external networks, on which the API services will be
exposed. The variable will be passed through to the ``kolla_internal_fqdn`` or
``kolla_external_fqdn`` Kolla Ansible variable.
To configure a network called ``example`` with an FQDN at ``api.example.com``:
.. code-block:: yaml
:caption: ``networks.yml``
example_fqdn: api.example.com
Configuring Static IP Routes
----------------------------
@ -116,6 +152,8 @@ To configure a network called ``example`` with VLAN ID ``123``:
example_vlan: 123
.. _configuration-network-ip-allocation:
IP Address Allocation
=====================

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@ -13,6 +13,9 @@
# Base path for kayobe state on remote hosts.
#base_path:
# Path in which to store configuration on remote hosts.
#config_path:
# Path in which to cache downloaded images on remote hosts.
#image_cache_path:
@ -25,8 +28,8 @@
###############################################################################
# User configuration.
# User with which to access seed and controller nodes. This user will be
# created if it does not exist.
# User with which to access remote hosts. This user will be created if it does
# not exist.
#kayobe_ansible_user:
###############################################################################