The LVM volume driver enables you to use the iSCSI protocol to connect to volumes in a volume group managed by the Linux Logical Volume Manager (LVM) on a storage node.

The LVM volume driver is supported only with Oracle Linux 7 storage nodes. You cannot use this driver with Oracle VM Server storage nodes.

The Cinder service (the enable_cinder property) and the LVM storage backend (the enable_cinder_backend_lvm property) are enabled by default.

By default, the Cinder service creates and manages the volumes in an LVM volume group named cinder-volumes on the storage nodes. If you prefer, you can configure a different LVM volume group name:

$ kollacli property set cinder_volume_group openstack-volumes

Whether you use the default LVM volume group name or your own, you have to manually create the LVM volume group on the storage nodes. Perform the following steps on each storage node:

For more information, see the lvm(8), pvcreate(8), vgcreate(8), and other LVM manual pages.

If you have dedicated storage appliances that support iSCSI volume drivers for Cinder, you can use these instead of, or in addition to, the Cinder LVM volume driver.

The Cinder service (the enable_cinder property) and the iSCSI storage backend (the enable_cinder_backend_iscsi property) are enabled by default.

To enable an iSCSI volume driver, you add the configuration settings for the driver to the /etc/kolla/config/cinder.conf file on the master node. If this file does not exist, create it. The format of the configuration settings is as follows:

[DEFAULT]
enabled_backends = MYdriver-1

[MYdriver-1]
volume_backend_name = name
volume_driver = cinder.volume.drivers.driver_name
setting_name = setting
...

The enabled_backends setting is required to enable the [MYdriver-1] configuration section. The volume_driver configuration setting is used to specify the volume driver, and the settings that follow this are specific to the selected volume driver.

For more information about the available Cinder volume drivers and their configuration settings, see the OpenStack Configuration Reference:

http://docs.openstack.org/mitaka/config-reference/block-storage/volume-drivers.html

For the Oracle ZFS Storage Appliance iSCSI driver, use:

volume_driver = cinder.volume.drivers.zfssa.zfssaiscsi.ZFSSAISCSIDriver

For more information about this driver, including the required configuration on the storage appliance itself, see http://docs.openstack.org/mitaka/config-reference/block-storage/drivers/zfssa-iscsi-driver.html.

The following is an example configuration for the Oracle ZFS Storage Appliance iSCSI driver:

enabled_backends = zfsISCSIdriver-1

[zfsISCSIdriver-1]
volume_backend_name = cinder-volumes
volume_driver = cinder.volume.drivers.zfssa.zfssaiscsi.ZFSSAISCSIDriver
san_ip = 10.10.10.10
san_login = cinder
san_password = password
zfssa_pool = mypool
zfssa_project = myproject
zfssa_initiator_username = iqn.name
zfssa_initiator_group = default
zfssa_target_portal = 10.10.10.11:3260
zfssa_target_interfaces = e1000g0

By default, the Cinder block storage service uses the iSCSI protocol to connect instances to volumes. The iscsid container runs on compute nodes and handles the iSCSI session using an iSCSI initiator name that is generated when you deploy Nova compute services.

If you prefer, you can configure your own iSCSI initiator name. You set the iSCSI initiator name in the /etc/iscsi/initiatorname.iscsi file on each compute node. If the initiatorname.iscsi file does not exist, create it. The file has one line, which contains the name of the initiator, in the format:

InitiatorName=iqn.yyyy-mm.naming-authority:unique_name

For example:

InitiatorName=iqn.1988-12.com.oracle:myiscsihost

The Nova compute service supports iSCSI multipath for failover purposes and increased performance. Multipath is enabled by default (configured with the enable_multipathd property). When multipath is enabled, the iSCSI initiator (the Compute node) is able to obtain a list of addresses from the storage node that the initiator can use as multiple paths to the iSCSI LUN.

The Cinder service provides the ability to back up Cinder volumes to an external storage. By default, the backup driver is configured to use NFS. However, you need to configure the NFS share as the location for the backups, as follows:

$ kollacli property set cinder_backup_share host_name:path

where host_name is the fully qualified DNS name or IP address of the host that exports the NFS share, and path is the full path to the share on that host.

You can configure separate shares for individual hosts or groups, see Section 4.5, “Setting Properties for Groups or Hosts” for details.

You can also configure mount options for the NFS share, as follows:

$ kollacli property set backup_mount_options_nfs nfs_mount-options

For example, by default Cinder supports NFS version 4.1 or higher. If the NFS host uses an earlier version of NFS, this can cause errors. To downgrade the NFS version, configure the NFS version as a mount option. For example to specify that NFS version 4 is used:

$ kollacli property set backup_mount_options_nfs "vers=4,minorversion=0"

If you enable the Swift object storage service (see Section 4.12, “Setting up Swift” for details), you can back up Cinder volumes to Swift instead of an NFS share. To do this you, need to change the default backup driver, as follows:

$ kollacli property set cinder_backup_driver swift