volume mirror start

Starts mirroring on the specified volume from its source volume.

  • License required: Enterprise Edition
  • Permissions required: fc or restore on the volume

When a mirror is started, the mirror volume is synchronized from a hidden internal snapshot so that the mirroring process is not affected by any concurrent changes to the source volume. The volume mirror start command does not wait for mirror completion, but returns immediately. The changes to the mirror volume occur atomically at the end of the mirroring process; deltas transmitted from the source volume do not appear until mirroring is complete.

To provide rollback capability for the mirror volume, the mirroring process creates a snapshot of the mirror volume before starting the mirror, with the following naming format: <volume>.mirrorsnap.<date>.<time>.

Normally, the mirroring operation transfers only deltas from the last successful mirror. Under certain conditions (mirroring a volume repaired by fsck, for example), the source and mirror volumes can become out of sync. In such cases, it is impossible to transfer deltas, because the state is not the same for both volumes. Use the -full option to force the mirroring operation to transfer all data to bring the volumes back in sync.

NOTE
If you are creating a local mirror of the root volume, root(/) points to the mirror volume, hence root is read-only. For read-write copy of root (/), you must use the special path, /.rw

Syntax

CLI
maprcli volume mirror start
    [ -cluster <cluster> ]
    [ -full true|false ]
    -name <volume name>
REST
Request Type POST
Request URL
http[s]://<host>:<port>/rest/volume/mirror/start?<parameters> 

Parameters

Parameter Description
cluster The cluster on which to run the command.
full Specifies whether to perform a full copy of all data. If false, only the deltas are copied.
name The volume for which to start the mirror.

Output

Sample Output

messages                                            
Started mirror operation for volumes 'testMirror'  

Examples

Start mirroring the mirror volume "testMirror":

maprcli volume mirror start -name testMirror
https://abc.sj.us:8443/rest/volume/mirror/start?name=testMirror