2.9. Managing LUN Snapshots¶
You can create and manage snapshots of specific LUNs. To create a snapshot of the entire target, you need to create snapshots of each LUN within it.
2.9.1. Creating LUN Snapshots¶
To create a snapshot of a LUN in an iSCSI target, use the vstorage-iscsi snapshot-create command. For example, for LUN 1 on target iqn.2014-04.com.vstorage:test1:
# vstorage-iscsi snapshot-create -t iqn.2014-04.com.vstorage:test1 -l 1
Snapshot a1f54314-bc06-40c6-a587-965feb9d85bb successfully created.
Note
To generate a UUID manually, use uuidgen.
2.9.2. Listing LUN Snapshots¶
To list snapshots for the specified LUN, use the vstorage-iscsi snapshot-list command. For example, for LUN 1 on target iqn.2014-04.com.vstorage:test1:
# vstorage-iscsi snapshot-list -t iqn.2014-04.com.vstorage:stor4 -l 1
CREATED C UUID PARENT_UUID
2014-04-11 13:16:51 a1f54314-bc06-40c6-a587-{...} 00000000-0000-0000-{...}
2014-04-11 13:16:57 * 9c98b442-7482-4fd0-9c45-{...} a1f54314-bc06-40c6-{...}
In the output above, the asterisk in the column C indicates the current snapshot, while the column PARENT_UUID shows snapshot dependency or history.
2.9.3. Switching Between LUN Snapshots¶
To switch to the specified LUN snapshot, use the vstorage-iscsi snapshot-switch command. For example:
# vstorage-iscsi snapshot-switch -u a1f54314-bc06-40c6-a587-965feb9d85bb
After you switch to a snapshot, the current LUN image will be removed.
Note
You can only switch between snapshots, if the LUN is offline.
2.9.4. Viewing LUN Snapshot Information¶
To view information about the specified snapshot, use the vstorage-iscsi snapshot-info command. For example:
# vstorage-iscsi snapshot-info -u 9c98b442-7482-4fd0-9c45-9259374ca84e
Target: iqn.2014-04.com.vstorage:stor4
LUN: 1
Created: 2014-04-11 13:16:57
Parent: 00000000-0000-0000-0000-000000000000}
{a1f54314-bc06-40c6-a587-965feb9d85bb}
{9c98b442-7482-4fd0-9c45-9259374ca84e
Description: None
2.9.5. Deleting LUN Snapshots¶
To delete the specifed LUN snapshot, use the vstorage-iscsi snapshot-delete command. For example:
# vstorage-iscsi snapshot-delete -u a1f54314-bc06-40c6-a587-965feb9d85bb
If the snapshot has no any children, it will be deleted. If the snapshot has a single child, it will be merged to that child.
Note
- You can only delete offline snapshots.
- Deleting a snapshot that has multiple children is currently not supported.