On 2016-08-25 12:06, Edward Rolison wrote:

I'm migrating a bunch of volumes from a 7 mode filer, to CDOT.

For various reasons, I'd _like_ to split these volumes apart prior to
migration - mostly around filecount. We have a few qtrees with really high
file counts, and generally they don't make sense to group together anyway.

Splitting up file trees that have grown too large in this way is often desirable when migrating, but you should avoid doing it with this messing around with QSM and VSM.
Instead you should best use the NetApp tool xcp, which was created for the purpose of effective 7m -> C.DOT migration of data.  It works over NFS, so there's no problem with compatibility.

With this you can use a suported SnapMirrir 7m -> C.DOT for the bulk of the data, pick out parts that you do with xcp and then delete the superflous files afterwards (when it has landed on C.DOT, after your cut over window). Hopefully you have some extra swing space to be able to pull this off, if not then...

Yes, I know it's daunting w.r.t. Very High Filecount. But it's still the best way IMO... rsync is impossible due to the traversing of all the inodes it does every single time on source and target, xcp keeps track of a state that avoids this and it has its own NFS stack built in, which makes it a very different and effective animal than anything else I've ever seen or herad of

/M

So - what I'm thinking is:

QSM from source qtree to 'staging' volume within filer.
VSM from staging volume to CDOT TDP volume.

Should I be able to do this, or is there a better way?

Ideally - I'd like to avoid a 'double cutover' scenario. My 'plan B'
involves just creating about 10 replicas of the source volume, and - post
cutover - delete all the stuff I didn't need from each of them, but this
seems a suboptimal solution. (I think I have the same problem, in that I
can't lower the inodes of the volume, so I'll have 10 volumes with 100M+
inodes, instead of 10 with considerably fewer)

It certainly seems like a TDP snapmirror doesn't work when a QSM is inbound
to the volume in question - but a break and resync _might_ do the trick?
(trying to do that now)

Is there a better approach I should be taking?

_______________________________________________
Toasters mailing list
Toasters@teaparty.net
http://www.teaparty.net/mailman/listinfo/toasters