Listing SnapMirror snapshots

About SnapMirror listing

You can use the Data ONTAP snap list command to list all snapshots, including the SnapMirror-specific snapshots, that are stored on your filer.

To list all the snapshots on your system, complete the following step.

Step

Action

1
In the console of either your source or destination filer, enter the following command:

snap list vol_name

Result

A listing of all snapshots stored on your system appears. SnapMirror snapshots are distinguished from system snapshots by a more elaborate naming convention and the label "snapmirror" in parentheses.

Step	Action
1	In the console of either your source or destination filer, enter the following command: snap list vol_name Result A listing of all snapshots stored on your system appears. SnapMirror snapshots are distinguished from system snapshots by a more elaborate naming convention and the label "snapmirror" in parentheses.

Naming conventions for snapshots used by SnapMirror

When you run the snap list command, SnapMirror snapshots are distinguished from the regular filer system snapshots by their naming conventions.

For volume replication, SnapMirror creates a snapshot of the whole source volume that is copied to the destination volume. For qtree replication, SnapMirror creates snapshots of one or more source qtrees on the source volume that are copied to a qtree on the destination volume.

A SnapMirror volume snapshot name is in the following format:

dest_filer(sysid)_name.number

dest_filer is the host name of the destination filer.

sysid is the destination system ID number.

name is the name of the destination volume.

number is the number of successful transfers for the snapshot, starting at 1. Data ONTAP increments this number for each transfer.

A SnapMirror qtree snapshot name is in the following format:

dest_filer(sysid)_name-src|dst.number

dest_filer is the host name of the destination filer.

sysid is the destination system ID number.

name is the name of the destination volume or qtree path.

src|dst is the source or destination name.

number is an arbitrary start point number for the snapshot. Data ONTAP increments this number for each transfer.

In the output of the snap list command, SnapMirror snapshots are followed by the SnapMirror name in parentheses.

Volume example

filerA(0016791363)_vol0.9 (snapmirror)

Qtree example

filerA(0016789302)_vol1_qtree3-dst.15 (snapmirror)

Caution
Do not delete manually created snapshots marked "snapmirror" in the output of the snap list command.

Using snap list to show SnapMirror updates on the destination volume

The following example describes SnapMirror snapshots that are created on a source volume and copied to a destination volume. In this example, data is copied from vol1 of filerA (the source) to vol2 of filerB (the destination).

To create a baseline version of a destination volume, filerA creates a snapshot named filerB(0016782130)_vol2.1 on filerA. All snapshots in vol1 of filerA, including filerB(0016782130)_vol2.1, are transferred to vol2 of filerB. When replicating a qtree, SnapMirror transfers only the qtree's data in the snapshot for the qtree.

If the administrator were to run the snap list command on the destination filerB after the filerB(0016782130)_vol2.1 snapshot was transferred from filerA to filerB, a listing similar to the following example would be generated.

filerB> snap list vol2

working.....

%/used    %/total  date          name

-------- --------  ------------  --------

0% ( 0%) 0% ( 0%)  Nov 17 10:50  filerB(0016782130)_vol2.1 
(snapmirror)

1% ( 0%) 0% ( 0%)  Nov 17 10:00  hourly.0

1% ( 0%) 0% ( 0%)  Nov 17 00:00  nightly.0

1% ( 0%) 0% ( 0%)  Nov 15 16:00  hourly.1

1% ( 0%) 1% ( 0%)  Nov 15 15:00  hourly.2

2% ( 0%) 1% ( 0%)  Nov 15 14:00  hourly.3

2% ( 0%) 1% ( 0%)  Nov 15 13:00  hourly.4

2% ( 0%) 1% ( 0%)  Nov 15 12:00  hourly.5

When it is time to update the destination, another snapshot is created on filerA.

The snap list command on filerA would generate the following display after the filerB(0016782130)_vol2.2 snapshot was created on filerA:

filerA> snap list vol1

working....

%/used   %/total     date          name

-------- ----------  ------------  --------

0% ( 0%) 0% ( 0%)    Nov 17 10:52  filerB(0016782130)_vol2.2 
(snapmirror)

0% ( 0%) 0% ( 0%)    Nov 17 10:51  filerB(0016782130)_vol2.1 
(snapmirror)

1% ( 0%) 0% ( 0%)    Nov 17 10:00  hourly.0

1% ( 0%) 0% ( 0%)    Nov 17 00:00  nightly.0

1% ( 0%) 0% ( 0%)    Nov 15 16:00  hourly.1

1% ( 0%) 1% ( 0%)    Nov 15 15:00  hourly.2

After the filerB(0016782130)_vol2.2 snapshot is transferred from filerA to filerB, both snapshots exist on filerB. On filerA, however, filerB(0016782130)_vol2.1 is no longer needed and is deleted; only filerB(0016782130)_vol2.2 is retained to be used for the next transfer.

You can see a list of each SnapMirror snapshot on the server, and the qtrees it contains, and the client sources of those qtrees and their timestamps by using the snap list -q command.

You can use the snap list -o command to display the names, timestamps, and sources (if they are copies) of the qtrees in a specified volume or at a path name.