Adding a block device to an existing LVM volume group

Use the following instructions to add a block device to an existing LVM volume group on a block storage node. You can do this at any time.

Before you begin

Note: Not supported for the HA controller +n compute topology.

Identify the block devices that you want to use on the block storage node. This can be an entire disk (for example, /dev/sdb) or a partition (for example, /dev/sdba). You can use tools like df and pvs to identify devices that are used by existing mounted file system or LVM volume groups.
Create an LVM physical volume over each block device using the pvcreate command. To create an LVM physical volume for /dev/sdb, use this command:
```
# pvcreate /dev/sdb
```
Extend the LVM volume group using the physical volume or volumes you previously created:
```
# vgextend cinder-volumes /dev/sdb [additional devices]
```