Netapp Volume DataMotion Highlights

Today i have performed Netapp DataMotion for volumes to migrate volumes from One Aggregate to another aggregate and i can see DataMotion uses SNAPMIRROR in the back end to move the data from OLD VOLUME to the NEW VOLUME. Please find the brief summary below how it works...

Note :- My volumes has ORACLE DB running on them and i have seen no disruption to the application during DataMotion it went smooth and Hassle Free.

prodfiler4> vol move start production_vol_adm ataggr0 -k

Use " -k " option if you want to keep the source volume as once after the VOL MOVE , Netapp destroys the source volume as all the new reads and writes were directed to the New Volume ( Destination Volume)

prodfiler4> Wed Feb 26 16:14:50 SGT [prodfiler4:vol.move.Start:info]: Move of volume production_vol_adm to aggr ataggr0 started
Creation of volume 'ndm_dstvol_1393402490' with size 21474836480  on containing aggregate
'ataggr0' has completed.

Volume 'ndm_dstvol_1393402490' is now restricted.

Wed Feb 26 16:15:13 SGT [prodfiler4:vol.move.transferStart:info]: Baseline transfer from volume production_vol_adm to ndm_dstvol_1393402490 started.
Transfer started.

Monitor progress with 'snapmirror status' or the snapmirror log.

Wed Feb 26 16:16:54 SGT prodfiler4:vol.move.transferStatus:info]: Baseline transfer from volume production_vol_adm to ndm_dstvol_1393402490 took 97 secs and transferred 1935528 KB data.

Wed Feb 26 16:16:56 SGT [prodfiler4:vol.move.transferStart:info]: Update from volume production_vol_adm to ndm_dstvol_1393402490 started.
Transfer started.

Monitor progress with 'snapmirror status' or the snapmirror log.

Wed Feb 26 16:17:18 SGT [prodfiler4:vol.move.transferStatus:info]: Update from volume production_vol_adm to ndm_dstvol_1393402490 took 13 secs and transferred 1160 KB data.

Wed Feb 26 16:17:23 SGT [prodfiler4:vol.move.transferStart:info]: Update from volume production_vol_adm to ndm_dstvol_1393402490 started.
Transfer started.

Monitor progress with 'snapmirror status' or the snapmirror log.

Wed Feb 26 16:17:44 SGT [prodfiler4:vol.move.transferStatus:info]: Update from volume production_vol_adm to ndm_dstvol_1393402490 took 12 secs and transferred 1104 KB data.

Wed Feb 26 16:17:44 SGT [prodfiler4:vol.move.updateTimePrediction:info]: Expected time for next update from volume production_vol_adm to ndm_dstvol_1393402490 is 12 secs to transfer 272 KB data.

Wed Feb 26 16:17:52 SGT [prodfiler4:vol.move.cutoverStart:info]: Cutover started for vol move of volume production_vol_adm to aggr ataggr0.
Transfer started.

Monitor progress with 'snapmirror status' or the snapmirror log.

prodfiler4> vol move status production_vol_adm
Source                Destination                     CO Attempts    CO Time     State
production_vol_adm    ataggr0                         3              60          cutover

prodfiler4> Wed Feb 26 16:18:07 SGT [prodfiler4:vol.move.cutoverEnd:info]: Cutover finished for vol move of volume production_vol_adm to aggregate ataggr0 - time taken 14 secs

prodfiler4> vol move status production_vol_adm
Source                Destination                     CO Attempts    CO Time     State
production_vol_adm    ataggr0                         3              60          cutover

prodfiler4> Wed Feb 26 16:18:16 SGT [prodfiler4:wafl.vvol.renamed:info]: Volume 'ndm_dstvol_1393402490' renamed to 'production_vol_adm_old_1393402490'.
'ndm_dstvol_1393402490' renamed to 'production_vol_adm_old_1393402490'
Wed Feb 26 16:18:17 SGT [prodfiler4:vol.move.End:info]: Successfully completed move of volume production_vol_adm to aggr ataggr0.



I have observed one important thing during the DataMotion is that you SOURCE VOLUME should have atleast 10% of FREE_SPACE left in it if not you may face issue during cut_over time as once after the base transfer it creates a snapshot on the Source Volume and do the updates based on the snapshot if you don't have enough space to create snapshots it will just show you transferring updates for more than 5 times which means you have to abort the DataMotion and increase the SOURCE VOLUME size and then start over again.

One more Important thing is the snap autodelete commitment settings on the volume should be set to Try 

Ex:- snap autodelete production_vol_adm commitment try ( Set this before initiating DataMotion )