Manage volumes¶

The default OpenStack Block Storage service implementation is an iSCSI solution that uses Logical Volume Manager (LVM) for Linux.

This high-level procedure shows you how to create and attach a volume to a server instance.

To create and attach a volume to an instance

1. Configure the OpenStack Compute and the OpenStack Block Storage services through the cinder.conf file.
2. Use the cinder create command to create a volume. This command creates an LV into the volume group (VG) cinder-volumes.
3. Use the nova volume-attach command to attach the volume to an instance. This command creates a unique iSCSI IQN that is exposed to the compute node.
   • The compute node, which runs the instance, now has an active iSCSI session and new local storage (usually a /dev/sdX disk).
   • Libvirt uses that local storage as storage for the instance. The instance gets a new disk (usually a /dev/vdX disk).

For this particular walk through, one cloud controller runs nova-api, nova-scheduler, nova-objectstore, nova-network and cinder-* services. Two additional compute nodes run nova-compute. The walk through uses a custom partitioning scheme that carves out 60 GB of space and labels it as LVM. The network uses the FlatManager and NetworkManager settings for OpenStack Compute.

The network mode does not interfere with OpenStack Block Storage operations, but you must set up networking for Block Storage to work. For details, see Networking.

To set up Compute to use volumes, ensure that Block Storage is installed along with lvm2. This guide describes how to troubleshoot your installation and back up your Compute volumes.