====================================== Dell EMC POWERMAX iSCSI and FC drivers ====================================== The Dell EMC PowerMax drivers, ``PowerMaxISCSIDriver`` and ``PowerMaxFCDriver``, support the use of Dell EMC PowerMax and VMAX storage arrays with the Cinder Block Storage project. They both provide equivalent functions and differ only in support for their respective host attachment methods. The drivers perform volume operations by communicating with the back-end PowerMax storage management software. They use the Requests HTTP library to communicate with a Unisphere for PowerMax instance, using a RESTAPI interface in the backend to perform PowerMax and VMAX storage operations. .. note:: While ``PowerMax`` will be used throughout this document, it will be used to collectively categorize the following supported arrays, PowerMax 2000, 8000, VMAX All Flash 250F, 450F, 850F and 950F and VMAX Hybrid. Please note That we will no longer be supporting the VMAX Hybrid in the ``T`` release of OpenStack. .. note:: KNOWN ISSUE: Workload support was dropped in PowerMax OS 5978. If a VMAX All Flash array is upgraded to PowerMax OS 5978 or greater and existing volume types leveraged workload i.e. DSS, DSS_REP, OLTP and OLTP_REP, attaching and detaching will no longer work and the volume type will be unusable. Refrain from upgrading to PowerMax OS 5978 or greater on an All Flash until a fix is merged. Please contact your Dell EMC PowerMax customer support representative if in any doubt. System requirements and licensing ================================= The Dell EMC PowerMax Cinder driver supports the VMAX-3 hybrid series, VMAX All-Flash series and the PowerMax arrays. Please note we will be no longer supporting the VMAX hybrid series in the ``T`` release of OpenStack. The array operating system software, Solutions Enabler 9.0.x series, and Unisphere for PowerMax 9.0.x series are required to run Dell EMC PowerMax Cinder driver. Download Solutions Enabler and Unisphere from the Dell EMC's support web site (login is required). See the ``Dell EMC Solutions Enabler 9.0.x Installation and Configuration Guide`` and ``Dell EMC Unisphere for PowerMax Installation Guide`` at ``support.emc.com``. Required PowerMax software suites for OpenStack ----------------------------------------------- There are five Dell EMC Software Suites sold with the VMAX Hybrid arrays: - Base Suite - Advanced Suite - Local Replication Suite - Remote Replication Suite - Total Productivity Pack The Dell EMC PowerMax Cinder driver requires the Advanced Suite and the Local Replication Suite or the Total Productivity Pack (it includes the Advanced Suite and the Local Replication Suite) for the VMAX Hybrid. Using PowerMax Remote Replication functionality will also require the Remote Replication Suite. For full functionality including SRDF for the VMAX All Flash, the FX package, or the F package plus the SRDF ``a la carte`` add on is required. The storage system also requires a Unisphere for PowerMax (SMC) eLicence. Each are licensed separately. For further details on how to get the relevant license(s), reference eLicensing Support below. eLicensing support ------------------ To activate your entitlements and obtain your PowerMax license files, visit the Service Center on ``_, as directed on your License Authorization Code (LAC) letter emailed to you. - For help with missing or incorrect entitlements after activation (that is, expected functionality remains unavailable because it is not licensed), contact your EMC account representative or authorized reseller. - For help with any errors applying license files through Solutions Enabler, contact the Dell EMC Customer Support Center. - If you are missing a LAC letter or require further instructions on activating your licenses through the Online Support site, contact EMC's worldwide Licensing team at ``licensing@emc.com`` or call: North America, Latin America, APJK, Australia, New Zealand: SVC4EMC (800-782-4362) and follow the voice prompts. EMEA: +353 (0) 21 4879862 and follow the voice prompts. Supported operations ==================== PowerMax drivers support these operations: - Create, list, delete, attach, and detach volumes - Create, list, and delete volume snapshots - Copy an image to a volume - Copy a volume to an image - Clone a volume - Extend a volume - Retype a volume (Host and storage assisted volume migration) - Create a volume from a snapshot - Create and delete generic volume group - Create and delete generic volume group snapshot - Modify generic volume group (add and remove volumes) - Create generic volume group from source - Live Migration - Volume replication SRDF/S, SRDF/A and SRDF Metro - Quality of service (QoS) - Manage and unmanage volumes and snapshots - List Manageable Volumes/Snapshots - Backup create, delete, list, restore and show PowerMax drivers also support the following features: - Dynamic masking view creation - Dynamic determination of the target iSCSI IP address - iSCSI multipath support - Oversubscription - Service Level support - SnapVX support - Compression support(All Flash and PowerMax) - Deduplication support(PowerMax) - CHAP Authentication - Multi-attach support - Volume Metadata in logs - Encrypted Volume support - Extending attached volume - Replicated volume retype support - Retyping attached(in-use) volume - Unisphere high availability(HA) support .. note:: VMAX All Flash array with Solutions Enabler 8.3.0.11 or later have compression enabled by default when associated with Diamond Service Level. This means volumes added to any newly created storage groups will be compressed. PowerMax naming conventions =========================== Masking view names ------------------ Masking views are dynamically created by the PowerMax FC and iSCSI drivers using the following naming conventions. ``[protocol]`` is either ``I`` for volumes attached over iSCSI or ``F`` for volumes attached over Fiber Channel. .. code-block:: text OS-[shortHostName]-[protocol]-[portgroup_name]-MV Initiator group names --------------------- For each host that is attached to PowerMax volumes using the drivers, an initiator group is created or re-used (per attachment type). All initiators of the appropriate type known for that host are included in the group. At each new attach volume operation, the PowerMax driver retrieves the initiators (either WWNNs or IQNs) from OpenStack and adds or updates the contents of the Initiator Group as required. Names are of the following format. ``[protocol]`` is either ``I`` for volumes attached over iSCSI or ``F`` for volumes attached over Fiber Channel. .. code-block:: console OS-[shortHostName]-[protocol]-IG .. note:: Hosts attaching to OpenStack managed PowerMax storage cannot also attach to storage on the same PowerMax that are not managed by OpenStack. FA port groups -------------- PowerMax array FA ports to be used in a new masking view are retrieved from the port group provided as the extra spec on the volume type, or chosen from the list provided in the Dell EMC configuration file. Storage group names ------------------- As volumes are attached to a host, they are either added to an existing storage group (if it exists) or a new storage group is created and the volume is then added. Storage groups contain volumes created from a pool, attached to a single host, over a single connection type (iSCSI or FC). ``[protocol]`` is either ``I`` for volumes attached over iSCSI or ``F`` for volumes attached over Fiber Channel. PowerMax Cinder driver utilizes cascaded storage groups - a ``parent`` storage group which is associated with the masking view, which contains ``child`` storage groups for each configured SRP/slo/workload/compression-enabled or disabled/replication-enabled or disabled combination. PowerMax, VMAX All Flash and Hybrid Parent storage group: .. code-block:: text OS-[shortHostName]-[protocol]-[portgroup_name]-SG Child storage groups: .. code-block:: text OS-[shortHostName]-[SRP]-[ServiceLevel/Workload]-[portgroup_name]-CD-RE .. note:: CD and RE are only set if compression is explicitly disabled or replication explicitly enabled. See the compression and replication sections below. .. note:: For PowerMax and any All Flash with PowerMax OS (5978) or greater, workload is NONE PowerMax Driver Integration =========================== 1. Prerequisites ---------------- #. Download Solutions Enabler from ``support.emc.com`` and install it. You can install Solutions Enabler on a non-OpenStack host. Supported platforms include different flavors of Windows, Red Hat, and SUSE Linux. Solutions Enabler can be installed on a physical server, or as a Virtual Appliance (a VMware ESX server VM). Additionally, starting with HYPERMAX OS Q3 2015, you can manage VMAX3 arrays using the Embedded Management (eManagement) container application. See the ``Dell EMC Solutions Enabler 9.0.x Installation and Configuration Guide`` on ``support.emc.com`` for more details. .. note:: You must discover storage arrays before you can use the PowerMax drivers. Follow instructions in ```Dell EMC Solutions Enabler 9.0.x Installation and Configuration Guide`` on ``support.emc.com`` for more details. #. Download Unisphere from ``support.emc.com`` and install it. Unisphere can be installed in local, remote, or embedded configurations - i.e., on the same server running Solutions Enabler; on a server connected to the Solutions Enabler server; or using the eManagement container application (containing Solutions Enabler and Unisphere for PowerMax). See ``Dell EMC Solutions Enabler 9.0.x Installation and Configuration Guide`` at ``support.emc.com``. 2. FC Zoning with PowerMax -------------------------- Zone Manager is required when there is a fabric between the host and array. This is necessary for larger configurations where pre-zoning would be too complex and open-zoning would raise security concerns. 3. iSCSI with PowerMax ---------------------- - Make sure the ``iscsi-initiator-utils`` package is installed on all Compute nodes. .. note:: You can only ping the PowerMax iSCSI target ports when there is a valid masking view. An attach operation creates this masking view. 4. Configure Block Storage in cinder.conf ----------------------------------------- .. note:: VMAX driver was rebranded to PowerMax in Stein, so some of the driver specific tags have also changed. Legacy tags like vmax_srp, vmax_array, vmax_service_level and vmax_port_group, as well as the old driver location, will continue to work until the 'V' release. .. config-table:: :config-target: PowerMax cinder.volume.drivers.dell_emc.powermax.common .. note:: For security and backend uniformity, the use of the XML file for PowerMax backend configuration was deprecated in Queens and removed entirely in Rocky. .. note:: ``san_api_port`` is ``8443`` by default but can be changed if necessary. For the purposes of this documentation the default is assumed so the tag will not appear in any of the ``cinder.conf`` extracts below. .. note:: PowerMax ``PortGroups`` must be pre-configured to expose volumes managed by the array. Port groups can be supplied in the ``cinder.conf``, or can be specified as an extra spec ``storagetype:portgroupname`` on a volume type. The latter gives the user more control. When a dynamic masking view is created by the PowerMax driver, if there is no port group specified as an extra specification, the port group is chosen randomly from the PortGroup list, to evenly distribute load across the set of groups provided. .. note:: Service Level and workload can be added to the cinder.conf when the backend is the default case and there is no associated volume type. This not a recommended configuration as it is too restrictive. Workload is NONE for PowerMax and any All Flash with PowerMax OS (5978) or greater. +--------------------+----------------------------+---------+----------+ | PowerMax parameter | cinder.conf parameter | Default | Required | +====================+============================+=========+==========+ | ServiceLevel | powermax_service_level | None | No | +--------------------+----------------------------+---------+----------+ | Workload | powermax_workload | None | No | +--------------------+----------------------------+---------+----------+ Configure Block Storage in cinder.conf Add the following entries to ``/etc/cinder/cinder.conf``: .. code-block:: ini enabled_backends = CONF_GROUP_ISCSI, CONF_GROUP_FC [CONF_GROUP_ISCSI] volume_driver = cinder.volume.drivers.dell_emc.powermax.iscsi.PowerMaxISCSIDriver volume_backend_name = POWERMAX_ISCSI powermax_port_groups = [OS-ISCSI-PG] san_ip = 10.10.10.10 san_login = my_username san_password = my_password powermax_array = 000123456789 powermax_srp = SRP_1 [CONF_GROUP_FC] volume_driver = cinder.volume.drivers.dell_emc.powermax.fc.PowerMaxFCDriver volume_backend_name = POWERMAX_FC powermax_port_groups = [OS-FC-PG] san_ip = 10.10.10.10 san_login = my_username san_password = my_password powermax_array = 000123456789 powermax_srp = SRP_1 In this example, two back-end configuration groups are enabled: ``CONF_GROUP_ISCSI`` and ``CONF_GROUP_FC``. Each configuration group has a section describing unique parameters for connections, drivers and the ``volume_backend_name``. 5. SSL support -------------- #. Get the CA certificate of the Unisphere server. This pulls the CA cert file and saves it as .pem file: .. code-block:: console # openssl s_client -showcerts \ -connect my_unisphere_host:8443 \ /dev/null \ | openssl x509 -outform PEM > my_unisphere_host.pem Where ``my_unisphere_host`` is the hostname of the unisphere instance and ``my_unisphere_host.pem`` is the name of the .pem file. #. Add this path to ``cinder.conf`` under the PowerMax backend stanza and set SSL verify to True .. code-block:: console driver_ssl_cert_verify = True driver_ssl_cert_path = /path/to/my_unisphere_host.pem ``OR`` follow the steps 3-6 below if you would like to add the CA cert to the system certificate bundle instead of specifying the path to cert: #. OPTIONAL: Copy the ``.pem`` cert to the system certificate directory and convert to ``.crt``: .. code-block:: console # cp my_unisphere_host.pem /usr/share/ca-certificates/ca_cert.crt #. OPTIONAL: Update CA certificate database with the following command. Ensure you select to enable the cert from step 3 when prompted: .. code-block:: console # sudo dpkg-reconfigure ca-certificates #. OPTIONAL: Set a system environment variable to tell the Requests library to use the system cert bundle instead of the default Certifi bundle: .. code-block:: console # export REQUESTS_CA_BUNDLE = /etc/ssl/certs/ca-certificates.crt #. OPTIONAL: Set cert verification to ``true`` under the PowerMax backend stanza in ``cinder.conf``: .. code-block:: console # driver_ssl_cert_verify = True #. Ensure ``driver_ssl_cert_path`` is set to ``True`` in ``cinder.conf`` backend stanza if steps 3-6 are skipped, otherwise ensure both ``driver_ssl_cert_path`` and ``driver_ssl_cert_path`` are set in ``cinder.conf`` backend stanza. 6. Create Volume Types ---------------------- Once the ``cinder.conf`` has been updated, :command:`openstack` commands need to be issued in order to create and associate OpenStack volume types with the declared ``volume_backend_names``. Additionally, each volume type will need an associated ``pool_name`` - an extra specification indicating the service level/ workload combination to be used for that volume type. There is also the option to assign a port group to a volume type by setting the ``storagetype:portgroupname`` extra specification. .. note:: It is possible to create as many volume types as the number of Service Level and Workload(available) combination for provisioning volumes. The pool_name is the additional property which has to be set and is of the format: ``+++``. This can be obtained from the output of the ``cinder get-pools--detail``. Workload is NONE for PowerMax or any All Flash with PowerMax OS (5978) or greater. .. code-block:: console $ openstack volume type create POWERMAX_ISCSI_SILVER_OLTP $ openstack volume type set --property volume_backend_name=ISCSI_backend \ --property pool_name=Silver+OLTP+SRP_1+000123456789 \ --property storagetype:portgroupname=OS-PG2 \ POWERMAX_ISCSI_SILVER_OLTP $ openstack volume type create POWERMAX_FC_DIAMOND_DSS $ openstack volume type set --property volume_backend_name=FC_backend \ --property pool_name=Diamond+DSS+SRP_1+000123456789 \ --property storagetype:portgroupname=OS-PG1 \ POWERMAX_FC_DIAMOND_DSS By issuing these commands, the Block Storage volume type ``POWERMAX_ISCSI_SILVER_OLTP`` is associated with the ``ISCSI_backend``, a Silver Service Level, and an OLTP workload. The type ``POWERMAX_FC_DIAMOND_DSS`` is associated with the ``FC_backend``, a Diamond Service Level, and a DSS workload. The ``ServiceLevel`` manages the underlying storage to provide expected performance. Setting the ``ServiceLevel`` to ``None`` means that non-FAST managed storage groups will be created instead (storage groups not associated with any service level). If ``ServiceLevel`` is ``None`` then ``Workload`` must be ``None``. .. code-block:: console openstack volume type set --property pool_name=None+None+SRP_1+000123456789 When a ``Workload`` is added, the latency range is reduced due to the added information. Setting the ``Workload`` to ``None`` means the latency range will be the widest for its Service Level type. Please note that you cannot set a Workload without a Service Level. .. code-block:: console openstack volume type set --property pool_name=Diamond+None+SRP_1+000123456789 .. note:: PowerMax and Hybrid support Optimized, Diamond, Platinum, Gold, Silver, Bronze, and NONE service levels. VMAX All Flash supports Diamond and None. Hybrid and All Flash support DSS_REP, DSS, OLTP_REP, OLTP, and None workloads, the latter up until ucode 5977. There is no support for workloads in PowerMax OS (5978) or greater. 7. Interval and Retries ----------------------- By default, ``interval`` and ``retries`` are ``3`` seconds and ``200`` retries respectively. These determine how long (``interval``) and how many times (``retries``) a user is willing to wait for a single Rest call, ``3*200=600seconds``. Depending on usage, these may need to be overridden by the user in the cinder.conf. For example, if performance is a factor, then the ``interval`` should be decreased to check the job status more frequently, and if multiple concurrent provisioning requests are issued then ``retries`` should be increased so calls will not timeout prematurely. In the example below, the driver checks every 3 seconds for the status of the job. It will continue checking for 200 retries before it times out. Add the following lines to the PowerMax backend in the cinder.conf: .. code-block:: console [CONF_GROUP_ISCSI] volume_driver = cinder.volume.drivers.dell_emc.powermax.iscsi.PowerMaxISCSIDriver volume_backend_name = POWERMAX_ISCSI powermax_port_groups = [OS-ISCSI-PG] san_ip = 10.10.10.10 san_login = my_username san_password = my_password powermax_array = 000123456789 powermax_srp = SRP_1 interval = 1 retries = 700 8. CHAP Authentication Support ------------------------------ This supports one way initiator CHAP authentication functionality into the PowerMax backend. With CHAP one-way authentication, the storage array challenges the host during the initial link negotiation process and expects to receive a valid credential and CHAP secret in response. When challenged, the host transmits a CHAP credential and CHAP secret to the storage array. The storagearray looks for this credential and CHAP secret which stored in the host initiator's initiator group (IG) information in the ACLX database. Once a positive authentication occurs, the storage array sends an acceptance message to the host. However, if the storage array fails to find any record of the credential/secret pair, it sends a rejection message, and the link is closed. Assumptions, Restrictions and Pre-Requisites ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #. The host initiator IQN is required along with the credentials the host initiator will use to log into the storage array with. The same credentials should be used in a multi node system if connecting to the same array. #. Enable one way CHAP authentication for the iscsi initiator on the storage array using SYMCLI. Template and example shown below. For the purpose of this setup, the credential/secret used would be my_username/my_password with iscsi initiator of iqn.1991-05.com.company.lcseb130 .. code-block:: console # symaccess -sid -iscsi \ {enable chap | disable chap | set chap} \ -cred -secret # symaccess -sid 128 \ -iscsi iqn.1991-05.com.company.lcseb130 \ set chap -cred my_username -secret my_password Settings and Configuration ~~~~~~~~~~~~~~~~~~~~~~~~~~ #. Set the configuration in the PowerMax backend group in cinder.conf using the following parameters and restart cinder. +-----------------------+-------------------------+-------------------+ | Configuration options | Value required for CHAP | Required for CHAP | +=======================+=========================+===================+ | use_chap_auth | True | Yes | +-----------------------+-------------------------+-------------------+ | chap_username | my_username | Yes | +-----------------------+-------------------------+-------------------+ | chap_password | my_password | Yes | +-----------------------+-------------------------+-------------------+ .. code-block:: ini [POWERMAX_ISCSI] volume_driver = cinder.volume.drivers.dell_emc.powermax.iscsi.PowerMaxISCSIDriver volume_backend_name = POWERMAX_ISCSI san_ip = 10.10.10.10 san_login = my_u4v_username san_password = my_u4v_password powermax_srp = SRP_1 powermax_array = 000123456789 powermax_port_groups = [OS-ISCSI-PG] use_chap_auth = True chap_username = my_username chap_password = my_password Usage ~~~~~ #. Using SYMCLI, enable CHAP authentication for a host initiator as described above, but do not set ``use_chap_auth``, ``chap_username`` or ``chap_password`` in ``cinder.conf``. Create a bootable volume. .. code-block:: console openstack volume create --size 1 \ --image \ --type \ test #. Boot instance named test_server using the volume created above: .. code-block:: console openstack server create --volume test \ --flavor m1.small \ --nic net-id=private \ test_server #. Verify the volume operation succeeds but the boot instance fails as CHAP authentication fails. #. Update the ``cinder.conf`` with ``use_chap_auth`` set to true and ``chap_username`` and ``chap_password`` set with the correct credentials. #. Rerun ``openstack server create`` #. Verify that the boot instance operation ran correctly and the volume is accessible. #. Verify that both the volume and boot instance operations ran successfully and the user is able to access the volume. 9. QoS (Quality of Service) support ----------------------------------- Quality of service (QoS) has traditionally been associated with network bandwidth usage. Network administrators set limitations on certain networks in terms of bandwidth usage for clients. This enables them to provide a tiered level of service based on cost. The Nova/Cinder QoS offer similar functionality based on volume type setting limits on host storage bandwidth per service offering. Each volume type is tied to specific QoS attributes some of which are unique to each storage vendor. In the hypervisor, the QoS limits the following: - Limit by throughput - Total bytes/sec, read bytes/sec, write bytes/sec - Limit by IOPS - Total IOPS/sec, read IOPS/sec, write IOPS/sec QoS enforcement in Cinder is done either at the hypervisor (front end), the storage subsystem (back end), or both. This section focuses on QoS limits that are enforced by either the PowerMax backend and the hypervisor front end interchangeably or just back end (Vendor Specific). The PowerMax driver offers support for Total bytes/sec limit in throughput and Total IOPS/sec limit of IOPS. The PowerMax driver supports the following attributes that are front end/back end agnostic - total_iops_sec - Maximum IOPs (in I/Os per second). Valid values range from 100 IO/Sec to 100,000 IO/sec. - total_bytes_sec - Maximum bandwidth (throughput) in bytes per second. Valid values range from 1048576 bytes (1MB) to 104857600000 bytes (100, 000MB) The PowerMax driver offers the following attribute that is vendor specific to the PowerMax and dependent on the total_iops_sec and/or total_bytes_sec being set. - Dynamic Distribution - Enables/Disables dynamic distribution of host I/O limits. Possible values are: - Always - Enables full dynamic distribution mode. When enabled, the configured host I/O limits will be dynamically distributed across the configured ports, thereby allowing the limits on each individual port to adjust to fluctuating demand. - OnFailure - Enables port failure capability. When enabled, the fraction of configured host I/O limits available to a configured port will adjust based on the number of ports currently online. - Never - Disables this feature (Default). USE CASE 1 - Default values ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Prerequisites - PowerMax - Host I/O Limit (MB/Sec) - No Limit - Host I/O Limit (IO/Sec) - No Limit - Set Dynamic Distribution - N/A .. table:: **Prerequisites - Block Storage (Cinder) back end (storage group)** +-------------------+-------------------+ | Key | Value | +===================+===================+ | total_iops_sec | 500 | +-------------------+-------------------+ | total_bytes_sec | 104857600 (100MB) | +-------------------+-------------------+ | DistributionType | Always | +-------------------+-------------------+ #. Create QoS Specs with the prerequisite values above: .. code-block:: console $ openstack volume qos create --consumer back-end \ --property total_iops_sec=500 \ --property total_bytes_sec=104857600 \ --property DistributionType=Always \ my_qos #. Associate QoS specs with specified volume type: .. code-block:: console $ openstack volume qos associate my_qos my_volume_type #. Create volume with the volume type indicated above: .. code-block:: console $ openstack volume create --size 1 --type my_volume_type my_volume **Outcome - PowerMax (storage group)** - Host I/O Limit (MB/Sec) - 100 - Host I/O Limit (IO/Sec) - 500 - Set Dynamic Distribution - Always **Outcome - Block Storage (Cinder)** Volume is created against volume type and QoS is enforced with the parameters above. USE CASE 2 - Preset limits ~~~~~~~~~~~~~~~~~~~~~~~~~~ Prerequisites - PowerMax - Host I/O Limit (MB/Sec) - 2000 - Host I/O Limit (IO/Sec) - 2000 - Set Dynamic Distribution - Never .. table:: **Prerequisites - Block Storage (Cinder) back end (storage group)** +-------------------+-------------------+ | Key | Value | +===================+===================+ | total_iops_sec | 500 | +-------------------+-------------------+ | total_bytes_sec | 104857600 (100MB) | +-------------------+-------------------+ | DistributionType | Always | +-------------------+-------------------+ #. Create QoS specifications with the prerequisite values above. The consumer in this case use case is both for front end and back end: .. code-block:: console $ openstack volume qos create --consumer back-end \ --property total_iops_sec=500 \ --property total_bytes_sec=104857600 \ --property DistributionType=Always \ my_qos #. Associate QoS specifications with specified volume type: .. code-block:: console $ openstack volume qos associate my_qos my_volume_type #. Create volume with the volume type indicated above: .. code-block:: console $ openstack volume create --size 1 --type my_volume_type my_volume #. Attach the volume created in step 3 to an instance .. code-block:: console $ openstack server add volume my_volume my_instance **Outcome - PowerMax (storage group)** - Host I/O Limit (MB/Sec) - 100 - Host I/O Limit (IO/Sec) - 500 - Set Dynamic Distribution - Always **Outcome - Block Storage (Cinder)** Volume is created against volume type and QoS is enforced with the parameters above. **Outcome - Hypervisor (Nova)** Libvirt includes an extra xml flag within the section called iotune that is responsible for rate limitation. To confirm that, first get the ``OS-EXT-SRV-ATTR:instance_name`` value of the server instance i.e. instance-00000003. .. code-block:: console $ openstack server show +-------------------------------------+-----------------------------------------------------------------+ | Field | Value | +-------------------------------------+-----------------------------------------------------------------+ | OS-DCF:diskConfig | AUTO | | OS-EXT-AZ:availability_zone | nova | | OS-EXT-SRV-ATTR:host | myhost | | OS-EXT-SRV-ATTR:hypervisor_hostname | myhost | | OS-EXT-SRV-ATTR:instance_name | instance-00000003 | | OS-EXT-STS:power_state | Running | | OS-EXT-STS:task_state | None | | OS-EXT-STS:vm_state | active | | OS-SRV-USG:launched_at | 2017-11-02T08:15:42.000000 | | OS-SRV-USG:terminated_at | None | | accessIPv4 | | | accessIPv6 | | | addresses | private=fd21:99c2:73f3:0:f816:3eff:febe:30ed, 10.0.0.3 | | config_drive | | | created | 2017-11-02T08:15:34Z | | flavor | m1.tiny (1) | | hostId | e7b8312581f9fbb8508587d45c0b6fb4dc86102c632ed1f3a6a49d42 | | id | 0ef0ff4c-dbda-4dc7-b8ed-45d2fc2f31db | | image | cirros-0.3.5-x86_64-disk (b7c220f5-2408-4296-9e58-fc5a41cb7e9d) | | key_name | myhostname | | name | myhosthame | | progress | 0 | | project_id | bae4b97a0d8b42c28a5add483981e5db | | properties | | | security_groups | name='default' | | status | ACTIVE | | updated | 2017-11-02T08:15:42Z | | user_id | 7bccf456740546799a7e20457f13c38b | | volumes_attached | | +-------------------------------------+-----------------------------------------------------------------+ We then run the following command using the ``OS-EXT-SRV-ATTR:instance_name`` retrieved above. .. code-block:: console $ virsh dumpxml instance-00000003 | grep -1 "total_bytes_sec\|total_iops_sec" The output of the command contains the xml below. It is found between the ```` start and end tag. .. code-block:: xml 104857600 500 USE CASE 3 - Preset limits ~~~~~~~~~~~~~~~~~~~~~~~~~~ Prerequisites - PowerMax - Host I/O Limit (MB/Sec) - 100 - Host I/O Limit (IO/Sec) - 500 - Set Dynamic Distribution - Always .. table:: **Prerequisites - Block Storage (Cinder) back end (storage group)** +-------------------+-------------------+ | Key | Value | +===================+===================+ | total_iops_sec | 500 | +-------------------+-------------------+ | total_bytes_sec | 104857600 (100MB) | +-------------------+-------------------+ | DistributionType | OnFailure | +-------------------+-------------------+ #. Create QoS specifications with the prerequisite values above: .. code-block:: console $ openstack volume qos create --consumer back-end \ --property total_iops_sec=500 \ --property total_bytes_sec=104857600 \ --property DistributionType=Always \ my_qos #. Associate QoS specifications with specified volume type: .. code-block:: console $ openstack volume qos associate my_qos my_volume #. Create volume with the volume type indicated above: .. code-block:: console $ openstack volume create --size 1 --type my_volume_type my_volume **Outcome - PowerMax (storage group)** - Host I/O Limit (MB/Sec) - 100 - Host I/O Limit (IO/Sec) - 500 - Set Dynamic Distribution - OnFailure **Outcome - Block Storage (Cinder)** Volume is created against volume type and QOS is enforced with the parameters above. USE CASE 4 - Default values ~~~~~~~~~~~~~~~~~~~~~~~~~~~ Prerequisites - PowerMax - Host I/O Limit (MB/Sec) - No Limit - Host I/O Limit (IO/Sec) - No Limit - Set Dynamic Distribution - N/A .. table:: **Prerequisites - Block Storage (Cinder) back end (storage group)** +-------------------+-----------+ | Key | Value | +===================+===========+ | DistributionType | Always | +-------------------+-----------+ #. Create QoS specifications with the prerequisite values above: .. code-block:: console $ openstack volume qos create --consumer back-end \ --property DistributionType=Always \ my_qos #. Associate QoS specifications with specified volume type: .. code-block:: console $ openstack volume qos associate my_qos my_volume_type #. Create volume with the volume type indicated above: .. code-block:: console $ openstack volume create --size 1 --type my_volume_type my_volume **Outcome - PowerMax (storage group)** - Host I/O Limit (MB/Sec) - No Limit - Host I/O Limit (IO/Sec) - No Limit - Set Dynamic Distribution - N/A **Outcome - Block Storage (Cinder)** Volume is created against volume type and there is no QoS change. 10. iSCSI multipathing support ------------------------------ - Install open-iscsi on all nodes on your system - Do not install EMC PowerPath as they cannot co-exist with native multipath software - Multipath tools must be installed on all Nova compute nodes On Ubuntu: .. code-block:: console # apt-get install multipath-tools #multipath modules # apt-get install sysfsutils sg3-utils #file system utilities # apt-get install scsitools #SCSI tools On openSUSE and SUSE Linux Enterprise Server: .. code-block:: console # zipper install multipath-tools #multipath modules # zipper install sysfsutils sg3-utils #file system utilities # zipper install scsitools #SCSI tools On Red Hat Enterprise Linux and CentOS: .. code-block:: console # yum install iscsi-initiator-utils #ensure iSCSI is installed # yum install device-mapper-multipath #multipath modules # yum install sysfsutils sg3-utils #file system utilities Multipath configuration file ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The multipath configuration file may be edited for better management and performance. Log in as a privileged user and make the following changes to :file:`/etc/multipath.conf` on the Compute (Nova) node(s). .. code-block:: vim devices { # Device attributed for EMC PowerMax device { vendor "EMC" product "SYMMETRIX" path_grouping_policy multibus getuid_callout "/lib/udev/scsi_id --page=pre-spc3-83 --whitelisted --device=/dev/%n" path_selector "round-robin 0" path_checker tur features "0" hardware_handler "0" prio const rr_weight uniform no_path_retry 6 rr_min_io 1000 rr_min_io_rq 1 } } You may need to reboot the host after installing the MPIO tools or restart iSCSI and multipath services. On Ubuntu: .. code-block:: console # service open-iscsi restart # service multipath-tools restart On openSUSE, SUSE Linux Enterprise Server, Red Hat Enterprise Linux, and CentOS: .. code-block:: console # systemctl restart open-iscsi # systemctl restart multipath-tools .. code-block:: console $ lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 1G 0 disk ..360000970000196701868533030303235 (dm-6) 252:6 0 1G 0 mpath sdb 8:16 0 1G 0 disk ..360000970000196701868533030303235 (dm-6) 252:6 0 1G 0 mpath vda 253:0 0 1T 0 disk OpenStack configurations ~~~~~~~~~~~~~~~~~~~~~~~~ On Compute (Nova) node, add the following flag in the ``[libvirt]`` section of :file:`/etc/nova/nova.conf` and :file:`/etc/nova/nova-cpu.conf`: .. code-block:: ini volume_use_multipath = True On Cinder controller node, iSCSI MPIO can be set globally in the [DEFAULT] section or set individually in the PowerMax backend stanza in :file:`/etc/cinder/cinder.conf`: .. code-block:: ini use_multipath_for_image_xfer = True Restart ``nova-compute`` and ``cinder-volume`` services after the change. Verify you have multiple initiators available on the compute node for I/O ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #. Create a 3GB PowerMax volume. #. Create an instance from image out of native LVM storage or from PowerMax storage, for example, from a bootable volume #. Attach the 3GB volume to the new instance: .. code-block:: console # multipath -ll mpath102 (360000970000196700531533030383039) dm-3 EMC,SYMMETRIX size=3G features='1 queue_if_no_path' hwhandler='0' wp=rw '-+- policy='round-robin 0' prio=1 status=active 33:0:0:1 sdb 8:16 active ready running '- 34:0:0:1 sdc 8:32 active ready running #. Use the ``lsblk`` command to see the multipath device: .. code-block:: console # lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdb 8:0 0 3G 0 disk ..360000970000196700531533030383039 (dm-6) 252:6 0 3G 0 mpath sdc 8:16 0 3G 0 disk ..360000970000196700531533030383039 (dm-6) 252:6 0 3G 0 mpath vda 11. All Flash compression support --------------------------------- On an All Flash array, the creation of any storage group has a compressed attribute by default. Setting compression on a storage group does not mean that all the devices will be immediately compressed. It means that for all incoming writes compression will be considered. Setting compression ``off`` on a storage group does not mean that all the devices will be uncompressed. It means all the writes to compressed tracks will make these tracks uncompressed. .. note:: This feature is only applicable for All Flash arrays, 250F, 450F, 850F and 950F and PowerMax 2000 and 8000. Use case 1 - Compression disabled create, attach, detach, and delete volume ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #. Create a new volume type called ``POWERMAX_COMPRESSION_DISABLED``. #. Set an extra spec ``volume_backend_name``. #. Set a new extra spec ``storagetype:disablecompression = True``. #. Create a new volume. #. Check in Unisphere or symcli to see if the volume exists in storage group ``OS----CD-SG``, and compression is disabled on that storage group. #. Attach the volume to an instance. Check in Unisphere or symcli to see if the volume exists in storage group ``OS-----CD``, and compression is disabled on that storage group. #. Detach volume from instance. Check in Unisphere or symcli to see if the volume exists in storage group ``OS----CD-SG``, and compression is disabled on that storage group. #. Delete the volume. If this was the last volume in the ``OS----CD-SG`` storage group, it should also be deleted. Use case 2 - Retype from compression disabled to compression enabled ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #. Repeat steps 1-4 of Use case 1. #. Create a new volume type. For example ``POWERMAX_COMPRESSION_ENABLED``. #. Set extra spec ``volume_backend_name`` as before. #. Set the new extra spec's compression as ``storagetype:disablecompression = False`` or DO NOT set this extra spec. #. Retype from volume type ``POWERMAX_COMPRESSION_DISABLED`` to ``POWERMAX_COMPRESSION_ENABLED``. #. Check in Unisphere or symcli to see if the volume exists in storage group ``OS----SG``, and compression is enabled on that storage group. .. note:: If extra spec ``storagetype:disablecompression`` is set on a hybrid, it is ignored because compression is not a feature on a VMAX3 hybrid. 12. Oversubscription support ---------------------------- Please refer to the following: :doc:`/admin/blockstorage-over-subscription`. 13. Live Migration support -------------------------- Non-live migration (sometimes referred to simply as 'migration'). The instance is shut down for a period of time to be moved to another hypervisor. In this case, the instance recognizes that it was rebooted. Live migration (or 'true live migration'). Almost no instance downtime. Useful when the instances must be kept running during the migration. The different types of live migration are: - Shared storage-based live migration. Both hypervisors have access to shared storage. - Block live migration. No shared storage is required. Incompatible with read-only devices such as CD-ROMs and Configuration Drive (config_drive). - Volume-backed live migration. Instances are backed by volumes rather than ephemeral disk. For PowerMax volume-backed live migration, shared storage is required. The PowerMax driver supports shared volume-backed live migration. Architecture ~~~~~~~~~~~~ In PowerMax, A volume cannot belong to two or more FAST storage groups at the same time. To get around this limitation we leverage both cascaded storage groups and a temporary non FAST storage group. A volume can remain 'live' if moved between masking views that have the same initiator group and port groups which preserves the host path. During live migration, the following steps are performed by the PowerMax driver on the volume: #. Within the originating masking view, the volume is moved from the FAST storage group to the non-FAST storage group within the parent storage group. #. The volume is added to the FAST storage group within the destination parent storage group of the destination masking view. At this point the volume belongs to two storage groups. #. One of two things happens: - If the connection to the destination instance is successful, the volume is removed from the non-FAST storage group in the originating masking view, deleting the storage group if it contains no other volumes. - If the connection to the destination instance fails, the volume is removed from the destination storage group, deleting the storage group, if empty. The volume is reverted back to the original storage group. Live migration configuration ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Please refer to the following for more information: https://docs.openstack.org/nova/latest/admin/live-migration-usage.html and https://docs.openstack.org/nova/latest/admin/configuring-migrations.html .. note:: OpenStack Oslo uses an open standard for messaging middleware known as AMQP. This messaging middleware (the RPC messaging system) enables the OpenStack services that run on multiple servers to talk to each other. By default, the RPC messaging client is set to timeout after 60 seconds, meaning if any operation you perform takes longer than 60 seconds to complete the operation will timeout and fail with the ERROR message "Messaging Timeout: Timed out waiting for a reply to message ID [message_id]" If this occurs, increase the ``rpc_response_timeout`` flag value in ``cinder.conf`` and ``nova.conf`` on all Cinder and Nova nodes and restart the services. What to change this value to will depend entirely on your own environment, you might only need to increase it slightly, or if your environment is under heavy network load it could need a bit more time than normal. Fine tuning is required here, change the value and run intensive operations to determine if your timeout value matches your environment requirements. At a minimum please set ``rpc_response_timeout`` to ``240``, but this will need to be raised if high concurrency is a factor. This should be sufficient for all Cinder backup commands also. System configuration ~~~~~~~~~~~~~~~~~~~~ ``NOVA-INST-DIR/instances/`` (for example, ``/opt/stack/data/nova/instances``) has to be mounted by shared storage. Ensure that NOVA-INST-DIR (set with state_path in the nova.conf file) is the same on all hosts. #. Configure your DNS or ``/etc/hosts`` and ensure it is consistent across all hosts. Make sure that the three hosts can perform name resolution with each other. As a test, use the ping command to ping each host from one another. .. code-block:: console $ ping HostA $ ping HostB $ ping HostC #. Export NOVA-INST-DIR/instances from HostA, and ensure it is readable and writable by the Compute user on HostB and HostC. Please refer to the relevant OS documentation for further details. e.g. https://help.ubuntu.com/lts/serverguide/network-file-system.html #. On all compute nodes, enable the 'execute/search' bit on your shared directory to allow qemu to be able to use the images within the directories. On all hosts, run the following command: .. code-block:: console $ chmod o+x NOVA-INST-DIR/instances .. note:: If migrating from compute to controller, make sure to run step two above on the controller node to export the instance directory. Use case ~~~~~~~~ For our use case shown below, we have three hosts with host names HostA, HostB and HostC. HostA is the compute node while HostB and HostC are the compute nodes. The following were also used in live migration. - 2 gb bootable volume using the cirros image. - Instance created using the 2gb volume above with a flavor m1.small using 2048 RAM, 20GB of Disk and 1 VCPU. #. Create a bootable volume. .. code-block:: console $ openstack volume create --size 2 \ --image cirros-0.3.5-x86_64-disk \ --volume_lm_1 #. Launch an instance using the volume created above on HostB. .. code-block:: console $ openstack server create --volume volume_lm_1 \ --flavor m1.small \ --nic net-id=private \ --security-group default \ --availability-zone nova:HostB \ server_lm_1 #. Confirm on HostB has the instance created by running: .. code-block:: console $ openstack server show server_lm_1 | grep "hypervisor_hostname\|instance_name" | OS-EXT-SRV-ATTR:hypervisor_hostname | HostB | OS-EXT-SRV-ATTR:instance_name | instance-00000006 #. Confirm, through virsh using the instance_name returned in step 3 (instance-00000006), on HostB that the instance is created using: .. code-block:: console $ virsh list --all Id Name State -------------------------------- 1 instance-00000006 Running #. Migrate the instance from HostB to HostA with: .. code-block:: console $ openstack server migrate --live HostA \ server_lm_1 #. Run the command on step 3 above when the instance is back in available status. The hypervisor should be on Host A. #. Run the command on Step 4 on Host A to confirm that the instance is created through virsh. 14. Multi-attach support ------------------------ PowerMax cinder driver supports the ability to attach a volume to multiple hosts/servers simultaneously. Please see :doc:`/admin/blockstorage-volume-multiattach` for configuration information. Multi-attach Architecture ~~~~~~~~~~~~~~~~~~~~~~~~~ In PowerMax, a volume cannot belong to two or more FAST storage groups at the same time. This can cause issues when we are attaching a volume to multiple instances on different hosts. To get around this limitation, we leverage both cascaded storage groups and non-FAST storage groups (i.e. a storage group with no service level, workload, or SRP specified). .. note:: If no service level is assigned to the volume type, no extra work on the backend is required – the volume is attached to and detached from each host as normal. Example Use Case ~~~~~~~~~~~~~~~~ Volume ``Multi-attach-Vol-1`` (with a multi-attach capable volume type, and associated with a Diamond Service Level) is attached to Instance ``Multi-attach-Instance-A`` on HostA. We then issue the command to attach ``Multi-attach-Vol-1`` to ``Multi-attach-Instance-B`` on HostB: #. In the HostA masking view, the volume is moved from the FAST managed storage group to the non-FAST managed storage group within the parent storage group. #. The volume is attached as normal on Host B – i.e., it is added to a FAST managed storage group within the parent storage group of the HostB masking view. The volume now belongs to two masking views, and is exposed to both HostA and HostB. We then decide to detach the volume from ‘Multi-attach-Instance-B’ on HostB: #. The volume is detached as normal from Host B – i.e., it is removed from the FAST managed storage group within the parent storage group of the HostB masking view – this includes cleanup of the associated elements if required. The volume now belongs to one masking view, and is no longer exposed to HostB. #. In the HostA masking view, the volume is returned to the FAST managed storage group from the non-FAST managed storage group within the parent storage group. The non-FAST managed storage group is cleaned up, if required. .. note:: Known issue - the multi-attach flag is still false after a retype. This is being addressed in https://bugs.launchpad.net/cinder/+bug/1790840 15. Volume Encryption support ----------------------------- Please refer to the following: :doc:`/configuration/block-storage/volume-encryption`. 16. Volume metadata in logs --------------------------- If debug is enabled in the default section of the cinder.conf, PowerMax Cinder driver will log additional volume information in the Cinder volume log, on each successful operation. The facilitates bridging the gap between OpenStack and the Array by tracing and describing the volume from a VMAX/ PowerMax view point. .. code-block:: console +------------------------------------+---------------------------------------------------------+ | Key | Value | +------------------------------------+---------------------------------------------------------+ | service_level | Gold | | is_compression_disabled | no | | powermax_cinder_driver_version | 3.2.0 | | identifier_name | OS-819470ab-a6d4-49cc-b4db-6f85e82822b7 | | openstack_release | 13.0.0.0b3.dev3 | | volume_id | 819470ab-a6d4-49cc-b4db-6f85e82822b7 | | storage_model | PowerMax_8000 | | successful_operation | delete | | default_sg_name | OS-DEFAULT_SRP-Gold-NONE-SG | | device_id | 01C03 | | unisphere_for_powermax_version | V9.0.0.9 | | workload | NONE | | openstack_version | 13.0.0 | | volume_updated_time | 2018-08-03 03:13:53 | | platform | Linux-4.4.0-127-generic-x86_64-with-Ubuntu-16.04-xenial | | python_version | 2.7.12 | | volume_size | 20 | | srp | DEFAULT_SRP | | openstack_name | 90_Test_Vol56 | | storage_firmware_version | 5978.143.144 | | serial_number | 000123456789 | +------------------------------------+---------------------------------------------------------+ 17. Unisphere high availability(HA) support ------------------------------------------- This feature facilitates high availability of Unisphere for PowerMax servers, allowing for one or more backup unisphere instances in the event of a loss in connection to the primary Unisphere instance. The PowerMax driver will cycle through the list of failover instances, trying each until a successful connection is made. The ordering is first in, first out (FIFO), so the first ``u4p_failover_target`` specified in ``cinder.conf`` will be the first selected, the second ``u4p_failover_target`` in ``cinder.conf`` will be the second selected, and so on until all failover targets are exhausted. Requirements ~~~~~~~~~~~~ - All required instances of Unisphere for PowerMax are set up and configured for the array(s) - Array(s) are locally registered with the instance of Unisphere that will be used as a failover instance. There are two failover types, local and remote: - `Local failover` - Primary Unisphere is unreachable, failover to secondary local instance of Unisphere to resume normal operations at primary site. - `Remote failover` - Complete loss of primary site so primary instance of Unisphere is unreachable, failover to secondary instance of Unisphere at remote site to resume operations with the R2 array. .. note:: Replication must be configured in advance for remote failover to work successfully. Human intervention will also be required to failover from R1 array to R2 array in Cinder using ``cinder failover-host`` command (see ``Volume replication support`` for replication setup details). .. note:: The remote target array must be registered as local to the remote instance of Unisphere Configuration ~~~~~~~~~~~~~ The following configuration changes need to be made in cinder.conf in order to support the failover to secondary Unisphere. Cinder services will need to be restarted for changes to take effect. .. code-block:: console u4p_failover_timeout = 30 u4p_failover_retries = 3 u4p_failover_backoff_factor = 1 u4p_failover_autofailback = True u4p_failover_target = san_ip:10.10.10.12, san_api_port: 8443, san_login:my_username, san_password:my_password, driver_ssl_cert_verify: False, u4p_failover_target = san_ip:10.10.10.13, san_api_port: 8443 san_login:my_username, san_password:my_password, driver_ssl_cert_verify: True, driver_ssl_cert_path: /path/to/my_unisphere_host.pem .. note:: ``u4p_failover_target`` key value pairs will need to be on the same line (separated by commas) in cinder.conf. They are displayed on separated lines above for readiblity. .. note:: To add more than one Unisphere failover target create additional ``u4p_failover_target`` details for the Unisphere instance. These will be cycled through in a first-in, first-out (FIFO) basis, the first failover target in ``cinder.conf`` will be the first backup instance of Unisphere used by the PowerMax driver. Cinder supported operations =========================== Volume replication support -------------------------- Configure the source and target arrays ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ #. Configure an SRDF group between the chosen source and target arrays for the PowerMax Cinder driver to use. The source array must correspond with the 'powermax_array' entry in the cinder.conf. #. Select both the director and the ports for the SRDF emulation to use on both sides. Bear in mind that network topology is important when choosing director endpoints. Supported modes are `Synchronous`, `Asynchronous`, and `Metro`. .. note:: If the source and target arrays are not managed by the same Unisphere server (that is, the target array is remotely connected to server - for example, if you are using embedded management), in the event of a full disaster scenario (i.e. the primary array is completely lost and all connectivity to it is gone), the Unisphere server would no longer be able to contact the target array. In this scenario, the volumes would be automatically failed over to the target array, but administrator intervention would be required to either; configure the target (remote) array as local to the current Unisphere server (if it is a stand-alone server), or enter the details of a second Unisphere server to the ``cinder.conf``, which is locally connected to the target array (for example, the embedded management Unisphere server of the target array), and restart the Cinder volume service. .. note:: If you are setting up an SRDF/Metro configuration, it is recommended that you configure a Witness or vWitness for bias management. Please see https://www.emc.com/collateral/technical-documentation/h14556-vmax3-srdf-metro-overview-and-best-practices-tech-note.pdf #. Enable replication in ``/etc/cinder/cinder.conf``. To enable the replication functionality in PowerMax Cinder driver, it is necessary to create a replication volume-type. The corresponding back-end stanza in the ``cinder.conf`` for this volume-type must then include a ``replication_device`` parameter. This parameter defines a single replication target array and takes the form of a list of key value pairs. .. code-block:: console enabled_backends = POWERMAX_FC_REPLICATION [POWERMAX_FC_REPLICATION] volume_driver = cinder.volume.drivers.dell_emc.powermax.fc.PowerMaxFCDriver san_ip = 10.10.10.10 san_login = my_u4v_username san_password = my_u4v_password powermax_srp = SRP_1 powermax_array = 000123456789 powermax_port_groups = [OS-FC-PG] volume_backend_name = POWERMAX_FC_REPLICATION replication_device = target_device_id:000197811111, remote_port_group:os-failover-pg, remote_pool:SRP_1, rdf_group_label: 28_11_07, allow_extend:False, mode:Metro, metro_use_bias:False, allow_delete_metro:False .. note:: ``replication_device`` key value pairs will need to be on the same line (separated by commas) in cinder.conf. They are displayed on separated lines above for readiblity. * ``target_device_id`` is a unique PowerMax array serial number of the target array. For full failover functionality, the source and target PowerMax arrays must be discovered and managed by the same U4V server. * ``remote_port_group`` is the name of a PowerMax port group that has been pre-configured to expose volumes managed by this backend in the event of a failover. Make sure that this portgroup contains either all FC or all iSCSI port groups (for a given back end), as appropriate for the configured driver (iSCSI or FC). * ``remote_pool`` is the unique pool name for the given target array. * ``rdf_group_label`` is the name of a PowerMax SRDF group that has been pre-configured between the source and target arrays. * ``allow_extend`` is a flag for allowing the extension of replicated volumes. To extend a volume in an SRDF relationship, this relationship must first be broken, both the source and target volumes are then independently extended, and then the replication relationship is re-established. If not explicitly set, this flag defaults to ``False``. .. note:: As the SRDF link must be severed, due caution should be exercised when performing this operation. If absolutely necessary, only one source and target pair should be extended at a time. .. note:: It is not currently possible to extend SRDF/Metro protected volumes. * ``mode`` is the required replication mode. Options are 'Synchronous', 'Asynchronous', and 'Metro'. This defaults to 'Synchronous'. * ``metro_use_bias`` is a flag to indicate if 'bias' protection should be used instead of Witness. This defaults to False. * ``allow_delete_metro`` is a flag to indicate if metro devices can be deleted. All Metro devices in an RDF group need to be managed together, so in order to delete one of the pairings, the whole group needs to be first suspended. Because of this, we require this flag to be explicitly set. This flag defaults to False. .. note:: Service Level and Workload: An attempt will be made to create a storage group on the target array with the same service level and workload combination as the primary. However, if this combination is unavailable on the target (for example, in a situation where the source array is a Hybrid, the target array is an All Flash, and an All Flash incompatible service level like Bronze is configured), no service level will be applied. .. note:: The PowerMax Cinder drivers can support a single replication target per back-end, that is we do not support Concurrent SRDF or Cascaded SRDF. Ensure there is only a single ``replication_device`` entry per back-end stanza. #. Create a ``replication-enabled`` volume type. Once the ``replication_device`` parameter has been entered in the PowerMax backend entry in the ``cinder.conf``, a corresponding volume type needs to be created ``replication_enabled`` property set. See above ``Setup PowerMax drivers`` for details. .. code-block:: console # openstack volume type set --property replication_enabled=" True" \ POWERMAX_FC_REPLICATION Volume replication interoperability with other features ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Most features are supported, except for the following: * Replication Group operations are available for volumes in Synchronous mode only. * Storage-assisted retype operations on replication-enabled PowerMax volumes (moving from a non-replicated type to a replicated-type and vice-versa. Moving to another service level/workload combination, for example) are not supported. * It is not currently possible to extend SRDF/Metro protected volumes. If a bigger volume size is required for a SRDF/Metro protected volume, this can be achieved by cloning the original volume and choosing a larger size for the new cloned volume. * The image volume cache functionality is supported (enabled by setting ``image_volume_cache_enabled = True``), but one of two actions must be taken when creating the cached volume: * The first boot volume created on a backend (which will trigger the cached volume to be created) should be the smallest necessary size. For example, if the minimum size disk to hold an image is 5GB, create the first boot volume as 5GB. * Alternatively, ensure that the ``allow_extend`` option in the ``replication_device parameter`` is set to ``True`` (Please note that it is not possible to extend SRDF/Metro protected volumes). This is because the initial boot volume is created at the minimum required size for the requested image, and then extended to the user specified size. Failover host ~~~~~~~~~~~~~ In the event of a disaster, or where there is required downtime, upgrade of the primary array for example, the administrator can issue the failover host command to failover to the configured target: .. code-block:: console # cinder failover-host cinder_host@POWERMAX_FC_REPLICATION If the primary array becomes available again, you can initiate a failback using the same command and specifying ``--backend_id default``: .. code-block:: console # cinder failover-host cinder_host@POWERMAX_FC_REPLICATION --backend_id default .. note:: Failover and Failback operations are not applicable in Metro configurations. Asynchronous and Metro replication management groups ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Asynchronous and Metro volumes in an RDF session, i.e. belonging to an SRDF group, must be managed together for RDF operations (although there is a ``consistency exempt`` option for creating and deleting pairs in an Async group). To facilitate this management, we create an internal RDF management storage group on the backend. It is crucial for correct management that the volumes in this storage group directly correspond to the volumes in the RDF group. For this reason, it is imperative that the RDF group specified in the ``cinder.conf`` is for the exclusive use by this Cinder backend. Metro support ~~~~~~~~~~~~~ SRDF/Metro is a High Availabilty solution. It works by masking both sides of the RDF relationship to the host, and presenting all paths to the host, appearing that they all point to the one device. In order to do this, there needs to be multipath software running to manage writing to the multiple paths. .. note:: There is an known issue on Unisphere for PowerMax where volumes are formatted when added to existing metro RDF Groups. The issue will only be addressed on arrays with PowerMax OS as the option not to format a metro volume is not available on HyperMax OS. Please refrain on cloning metro volumes until further notice. If in any doubt please contact your Dell EMC Representative. Known issues ~~~~~~~~~~~~ .. note:: Due to to nature of SRDF/Metro and issues around extending and cloning Metro devices we cannot support image_volume_cache_enabled=True on bootable Metro devices. .. note:: There is an known issue on Unisphere for PowerMax where volumes are formatted when added to existing metro RDF Groups. The issue will only be addressed on arrays with PowerMax OS as the option not to format a metro volume is not available on HyperMax OS. Please refrain on cloning metro volumes until further notice. If in any doubt please contact your Dell EMC Representative. .. note:: There is a known issue which can occasionally occur when certain operations on replicated volumes are invoked concurrently. This can cause some of these operations to fail, but they should be successful on subsequent attempts. Currently, this limitation applies to concurrent deletion of replicated volumes, and concurrent management of existing volumes into a replication volume type. Volume retype - storage assisted volume migration -------------------------------------------------- Volume retype with storage assisted migration is supported now for PowerMax arrays. Cinder requires that for storage assisted migration, a volume cannot be retyped across backends. For using storage assisted volume retype, follow these steps: #. For migrating a volume from one Service Level or Workload combination to another, use volume retype with the migration-policy to on-demand. The target volume type should have the same volume_backend_name configured and should have the desired pool_name to which you are trying to retype to (please refer to ``Setup PowerMax Drivers`` for details). .. code-block:: console $ cinder retype --migration-policy on-demand .. note:: With the Rocky release the following is now supported - Retype non-replicated volume to a replicated volume type - Retype replicated volume to a non-replicated volume type - Retype a replicated volume to a different replicated volume type .. note:: With the Stein release, In Use (attached) volume retype is supported Generic volume group support ---------------------------- Generic volume group operations are performed through the CLI using API version 3.1x of the Cinder API. Generic volume groups are multi-purpose groups which can be used for various features. The PowerMax driver supports consistent group snapshots and replication groups. Consistent group snapshots allows the user to take group snapshots which are consistent based on the group specs. Replication groups allow for/ tenant facing APIs to enable and disable replication, and to failover and failback, a group of volumes. Generic volume groups have replaced the deprecated consistency groups. Consistent group snapshot ~~~~~~~~~~~~~~~~~~~~~~~~~ To create a consistent group snapshot, set a group-spec, having the key ``consistent_group_snapshot_enabled`` set to `` True`` on the group. .. code-block:: console cinder --os-volume-api-version 3.11 group-type-key GROUP_TYPE set consistent_group_snapshot_enabled=" True" Similarly the same key should be set on any volume type which is specified while creating the group. .. code-block:: console # openstack volume type set --property replication_enabled=" True" / POWERMAX_REPLICATION If this key is not set on the group-spec or volume type, then the generic volume group will be created/managed by Cinder (not the PowerMax driver). .. note:: The consistent group snapshot should not be confused with the PowerMax consistency group which is an SRDF construct. Replication groups ~~~~~~~~~~~~~~~~~~ As with Consistent group snapshot ``consistent_group_snapshot_enabled`` should be set to true on the group and the volume type for replication groups. Only Synchronous replication is supported for use with Replication Groups. When a volume is created into a replication group, replication is on by default. The ``disable_replication`` api suspends I/O traffic on the devices, but does NOT remove replication for the group. The ``enable_replication`` api resumes I/O traffic on the RDF links. The "failover_group" api allows a group to be failed over and back without failing over the entire host. See below for usage. .. note:: A generic volume group can be both consistent group snapshot enabled and consistent group replication enabled. Storage Group Names ~~~~~~~~~~~~~~~~~~~ Storage groups are created on the PowerMax as a result of creation of generic volume groups. These storage groups follow a different naming convention and are of the following format depending upon whether the groups have a name. .. code-block:: text TruncatedGroupName_GroupUUID or GroupUUID Group type operations ~~~~~~~~~~~~~~~~~~~~~ - Create a group type .. code-block:: console cinder --os-volume-api-version 3.11 group-type-create GROUP_TYPE - Show a group type .. code-block:: console cinder --os-volume-api-version 3.11 group-type-show GROUP_TYPE - List group types .. code-block:: console cinder --os-volume-api-version 3.11 group-type-list - Delete group type .. code-block:: console cinder --os-volume-api-version 3.11 group-type-delete GROUP_TYPE - Set/unset a group spec .. code-block:: console cinder --os-volume-api-version 3.11 group-type-key GROUP_TYPE set consistent_group_snapshot_enabled=" True" - List group types and group specs: .. code-block:: console cinder --os-volume-api-version 3.11 group-specs-list Group operations ~~~~~~~~~~~~~~~~ - Create a group: .. code-block:: console cinder --os-volume-api-version 3.13 group-create --name GROUP GROUP_TYPE VOLUME_TYPE1,VOLUME_TYPE2 - Show a group: .. code-block:: console cinder --os-volume-api-version 3.13 group-show GROUP - List all groups: .. code-block:: console cinder --os-volume-api-version 3.13 group-list - Create a volume and add it to a group at the time of creation: .. code-block:: console cinder --os-volume-api-version 3.13 create --volume-type VOLUME_TYPE1 --group-id GROUP_ID 1 - Modify a group to add or remove volumes: .. code-block:: console cinder --os-volume-api-version 3.13 group-update --add-volumes UUID1,UUID2 --remove-volumes UUID3,UUID4 GROUP - Delete a group .. code-block:: console cinder --os-volume-api-version 3.13 group-delete --delete-volumes GROUP Group snapshot operations ~~~~~~~~~~~~~~~~~~~~~~~~~ - Create a group snapshot: .. code-block:: console cinder --os-volume-api-version 3.14 group-snapshot-create --name GROUP_SNAPSHOT GROUP - Delete group snapshot(s): .. code-block:: console cinder --os-volume-api-version 3.14 group-snapshot-delete GROUP_SNAPSHOT - Create a group from a group snapshot: .. code-block:: console $ cinder --os-volume-api-version 3.14 group-create-from-src --group-snapshot GROUP_SNAPSHOT --name GROUP - Create a group from a source snapshot: .. code-block:: console $ cinder --os-volume-api-version 3.14 group-create-from-src --source-group SOURCE_GROUP --name GROUP Group replication operations ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - Enable group replication .. code-block:: console cinder --os-volume-api-version 3.38 group-enable-replication GROUP - Disable group replication .. code-block:: console cinder --os-volume-api-version 3.38 group-disable-replication GROUP - Failover group .. code-block:: console cinder --os-volume-api-version 3.38 group-failover-replication GROUP - Failback group .. code-block:: console cinder --os-volume-api-version 3.38 group-failover-replication GROUP / --secondary-backend-id default Manage and Unmanage Volumes --------------------------- Managing volumes in OpenStack is the process whereby a volume which exists on the storage device is imported into OpenStack to be made available for use in the OpenStack environment. For a volume to be valid for managing into OpenStack, the following prerequisites must be met: - The volume exists in a Cinder managed pool - The volume is not part of a Masking View - The volume is not part of an SRDF relationship - The volume is configured as a TDEV (thin device) - The volume is set to FBA emulation - The volume must a whole GB e.g. 5.5GB is not a valid size - The volume cannot be a snapvx target For a volume to exist in a Cinder managed pool, it must reside in the same Storage Resource Pool (SRP) as the backend which is configured for use in OpenStack. Specifying the pool correctly can be entered manually as it follows the same format: .. code-block:: console Pool format: +++ Pool example 1: Diamond+DSS+SRP_1+111111111111 Pool example 2: Diamond+SRP_1+111111111111 .. list-table:: Pool values :header-rows: 1 * - Key - Value * - service_level - The service level of the volume to be managed * - workload - The workload of the volume to be managed * - SRP - The Storage Resource Pool configured for use by the backend * - array_id - The PowerMax serial number (12 digit numerical) Manage Volumes ~~~~~~~~~~~~~~ With your pool name defined you can now manage the volume into OpenStack, this is possible with the CLI command ``cinder manage``. The bootable parameter is optional in the command, if the volume to be managed into OpenStack is not bootable leave this parameter out. OpenStack will also determine the size of the value when it is managed so there is no need to specify the volume size. Command format: .. code-block:: console $ cinder manage --name --volume-type \ --availability-zone <--bootable> Command Example: .. code-block:: console $ cinder manage --name powermax_managed_volume --volume-type POWERMAX_ISCSI_DIAMOND \ --availability-zone nova demo@POWERMAX_ISCSI_DIAMOND#Diamond+SRP_1+111111111111 031D8 After the above command has been run, the volume will be available for use in the same way as any other OpenStack PowerMax volume. .. note:: An unmanaged volume with a prefix of 'OS-' in its identifier name cannot be managed into OpenStack, as this is a reserved keyword for managed volumes. If the identifier name has this prefix, an exception will be thrown by the PowerMax driver on a manage operation. Managing Volumes with Replication Enabled ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Whilst it is not possible to manage volumes into OpenStack that are part of a SRDF relationship, it is possible to manage a volume into OpenStack and enable replication at the same time. This is done by having a replication enabled PowerMax volume type (for more information see section Volume Replication) during the manage volume process you specify the replication volume type as the chosen volume type. Once managed, replication will be enabled for that volume. Unmanage Volume ~~~~~~~~~~~~~~~ Unmanaging a volume is not the same as deleting a volume. When a volume is deleted from OpenStack, it is also deleted from the PowerMax at the same time. Unmanaging a volume is the process whereby a volume is removed from OpenStack but it remains for further use on the PowerMax. The volume can also be managed back into OpenStack at a later date using the process discussed in the previous section. Unmanaging volume is carried out using the Cinder unmanage CLI command: Command format: .. code-block:: console $ cinder unmanage Command example: .. code-block:: console $ cinder unmanage powermax_test_vol Once unmanaged from OpenStack, the volume can still be retrieved using its device ID or OpenStack volume ID. Within Unisphere you will also notice that the 'OS-' prefix has been removed, this is another visual indication that the volume is no longer managed by OpenStack. Manage/Unmanage Snapshots ------------------------- Users can manage PowerMax SnapVX snapshots into OpenStack if the source volume already exists in Cinder. Similarly, users will be able to unmanage OpenStack snapshots to remove them from Cinder but keep them on the storage backend. Set-up, restrictions and requirements: #. No additional settings or configuration is required to support this functionality. #. Manage/Unmanage snapshots requires SnapVX functionality support on PowerMax. #. Manage/Unmanage Snapshots in OpenStack Cinder is only supported at present through Cinder CLI commands. #. It is only possible to manage or unmanage one snapshot at a time in Cinder. Manage SnapVX Snapshot ~~~~~~~~~~~~~~~~~~~~~~ It is possible to manage PowerMax SnapVX snapshots into OpenStack, where the source volume from which the snapshot is taken already exists in, and is managed by OpenStack Cinder. The source volume may have been created in OpenStack Cinder, or it may have been managed in to OpenStack Cinder also. With the support of managing SnapVX snapshots included in OpenStack Queens, the restriction around managing SnapVX source volumes has been removed. .. note:: It is not possible to manage into OpenStack SnapVX linked target volumes, or volumes which exist in a replication session. Requirements/Restrictions: #. The SnapVX source volume must be present in and managed by Cinder. #. The SnapVX snapshot name must not begin with ``OS-``. #. The SnapVX snapshot source volume must not be in a failed-over state. #. Managing a SnapVX snapshot will only be allowed if the snapshot has no linked target volumes. Command Structure: #. Identify your SnapVX snapshot for management on the PowerMax, note the name. #. Ensure the source volume is already managed into OpenStack Cinder, note the device ID. #. Using the Cinder CLI, use the following command structure to manage a Snapshot into OpenStack Cinder: .. code-block:: console $ cinder snapshot-manage --id-type source-name [--name ] [--description ] [--metadata [ [ ...]]] Positional arguments: - - Source OpenStack volume name - - Name of existing snapshot on PowerMax backend Optional arguments: - --name - Snapshot name (Default=None) - --description - Snapshot description (Default=None) - --metadata [ [ ...]] Metadata key=value pairs (Default=None) Example: .. code-block:: console $ cinder snapshot-manage --name SnapshotManaged \ --description "Managed Queens Feb18" \ 0021A PowerMaxSnapshot Where: - The name in OpenStack after managing the SnapVX snapshot will be ``SnapshotManaged``. - The snapshot will have the description ``Managed Queens Feb18``. - The source volume device ID is ``0021A``. - The name of the SnapVX snapshot on the PowerMax backend is ``PowerMaxSnapshot``. Outcome: After the process of managing the Snapshot has completed, the SnapVX snapshot on the PowerMax backend will be prefixed by the letters ``OS-``, leaving the snapshot in this example named ``OS-PowerMaxSnapshot``. The associated snapshot managed by Cinder will be present for use under the name ``SnapshotManaged``. Unmanage Cinder Snapshot ~~~~~~~~~~~~~~~~~~~~~~~~ Unmanaging a snapshot in Cinder is the process whereby the snapshot is removed from and no longer managed by Cinder, but it still exists on the storage backend. Unmanaging a SnapVX snapshot in OpenStack Cinder follows this behaviour, whereby after unmanaging a PowerMax SnapVX snapshot from Cinder, the snapshot is removed from OpenStack but is still present for use on the PowerMax backend. Requirements/Restrictions: - The SnapVX source volume must not be in a failed over state. Command Structure: Identify the SnapVX snapshot you want to unmanage from OpenStack Cinder, note the snapshot name or ID as specified by Cinder. Using the Cinder CLI use the following command structure to unmanage the SnapVX snapshot from Cinder: .. code-block:: console $ cinder snapshot-unmanage Positional arguments: - - Cinder snapshot name or ID. Example: .. code-block:: console $ cinder snapshot-unmanage SnapshotManaged Where: - The SnapVX snapshot name in OpenStack Cinder is SnapshotManaged. After the process of unmanaging the SnapVX snapshot in Cinder, the snapshot on the PowerMax backend will have the ``OS-`` prefix removed to indicate it is no longer OpenStack managed. In the example above, the snapshot after unmanaging from OpenStack will be named ``PowerMaxSnapshot`` on the storage backend. List manageable volumes and snapshots ------------------------------------- Manageable volumes ~~~~~~~~~~~~~~~~~~ Volumes that can be managed by and imported into Openstack. List manageable volume is filtered by: - Volume size should be 1026MB or greater (1GB PowerMax Cinder Vol = 1026 MB) - Volume size should be a whole integer GB capacity - Volume should not be a part of masking view. - Volume status should be ``Ready`` - Volume service state should be ``Normal`` - Volume emulation type should be ``FBA`` - Volume configuration should be ``TDEV`` - Volume should not be a system resource. - Volume should not be ``private`` - Volume should not be ``encapsulated`` - Volume should not be ``reserved`` - Volume should not be a part of an RDF session - Volume should not be a snapVX Target - Volume identifier should not begin with ``OS-``. Manageable snaphots ~~~~~~~~~~~~~~~~~~~ Snapshots that can be managed by and imported into Openstack List manageable snapshots is filtered by: - The source volume should be marked as SnapVX source. - The source volume should be 1026MB or greater - The source volume should be a whole integer GB capacity. - The source volume emulation type should be ``FBA``. - The source volume configuration should be ``TDEV``. - The source volume should not be ``private``. - The source volume should be not be a system resource. - The snapshot identifier should not start with ``OS-`` or ``temp-``. - The snapshot should not be expired. - The snapshot generation number should npt be greater than 0. .. note:: There is some delay in the syncing of the Unisphere for PowerMax database when the state/properties of a volume is modified using ``symcli``. To prevent this it is preferrable to modify state/properties of volumes within Unisphere. Cinder backup support --------------------- PowerMax cinder driver supports cinder backup functionality. See :doc:`/configuration/block-storage/backup-drivers` and https://docs.openstack.org/python-openstackclient/latest/cli/command-objects/backup.html for more details. Upgrading from SMI-S based driver to RESTAPI based driver ========================================================= Seamless upgrades from an SMI-S based driver to RESTAPI based driver, following the setup instructions above, are supported with a few exceptions: #. Live migration functionality will not work on already attached/in-use legacy volumes. These volumes will first need to be detached and reattached using the RESTAPI based driver. This is because we have changed the masking view architecture from Pike to better support this functionality. #. Consistency groups are deprecated in Pike. Generic Volume Groups are supported from Pike onwards.