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ndmpcopy across aggregates

Can ndmpcopy be used to migrate a volume between aggregates on the same controller and if so would all ntfs permissions  also be migrated?

Re: ndmpcopy across aggregates

Yes, you can use ndmpcopy. All NTFS permission will be transfered. Any reason, why you are choosing ndmpcopy to migrate volume, and not 'vol copy' or 'snapmirror' ?

Re: ndmpcopy across aggregates

Great thanks. I can't snapmirror as src and dest are on the same filer. Will vol copy work across aggrs?

Re: ndmpcopy across aggregates

You can snapmirror on the same filer.

filer>snapmirror initialize –S FILER1Smiley Surprisedldvol FILER1:newvol

Yes, voly copy work across aggrs. Both vol copy & snapmirror works at block level so its faster, whereas NDMPcopy works at file-lelve.

Some differences between vol copy & ndmpcopy:

cmd:
filer>vol copy start source_volume target_volume

Restrictions
•The destination volume must be >= the source volume size
•The source and destination volumes must be of same type (traditional, flexible, 32bit, or 64bit volumes).  To copy from 32bit to 64bit or from traditional to flexible you must use ndmpcopy.


If you wish to copy all snapshots then:
vol copy start src dst


If you wish to copy only specific snapshot then:
vol copy -S src dst

vol copy -S important_vol new_important_vol


cmd:
filer>ndmpcopy /vol/source_volume /vol/target_volume
Restrictions
•Snapshots can’t be copied from the source volume to the target volume.
•The console will not be available for other operations until the copy is completed.  This limits you to running one ndmpcopy command at a time.


The important differences between these 2 methods are as follows:

1. vol copy only copies entire volumes, ndmpcopy can copy at any level (even down to a single file).
2. vol copy is a level 0 copy only. Ndmpcopy can do file-level incrementals
3. vol copy is a physical copy, ndmpcopy is logical. Where this can matter is that vol copy doesn't care what your file layout is because it doesn't have to walk the directories. Ndmpcopy's performance can be affected by the data layout (e.g. lots of small files will perform worse than a few large ones, etc.). It also means that vol copy brings over all of the snapshots in one pass. Ndmpcopy doesn't do this.

In general vol copy is probably faster.

Re: ndmpcopy across aggregates

I am very glad I posted this question.. I did not know you could use snapmirror on the same filer. I also believe you cannot snapmirror between filers in the same HA pair, I am wrong here also?

If you can snapmirror does this mean you can also schedule snapmirror updates in an attempt to reduce your cutover time (to the new volume)?

Lastly, within your vol copy example for moving snapshots are you moving the vol first then each snapshot after the initial vol copy? IE:

vol copy start src dst ----- This takes the volume and all snaps

vol copy -S src dst ----- This takes volume ONLY

vol copy -S important_vol new_important_vol ----- This moves specific snaps to the new volume ???????

Re: ndmpcopy across aggregates

Yes, you can schedule snapmirror updates.

Small correction from my last example for vol copy :

Select one of the following commands based on your needs.

a.  Copy source volume to the target volume, do not copy the snapshots.

filer>vol copy start source_volume target_volume

b.  Copy source volume to the target volume, and one snapshot (nightly.1), whatever snapshot you choose.

filer>vol copy start -s nightly.1 source_volume target_volume

c.  Copy the source volume and all its snapshots to the target volume

filer>vol copy start -S source_volume target_volume

Thanks,

-Ashwin

Re: ndmpcopy across aggregates

You can schedule replications so that way when you are ready to migrate, less data will need to be migrated during the cut-over.

Add the schedule to /etc/snapmirror.conf

FILER1Smiley Surprisedldvol FILER1:newvol – 0 22 * *

Example: This scheduled replication runs every night at 10:00 PM.

Re: ndmpcopy across aggregates

Thanks - Can you mirror between filers in the same HA pair (7 mode)?

Re: ndmpcopy across aggregates

Yes, absolutely.