topic Re: First time DB copy using CA/XP in Disk Enclosures

First time DB copy using CA/XP

Srinikalyan — Tue, 03 Feb 2009 12:22:52 GMT

Hi,
My requirement is to copy the database(initial first time copy) of size 30TB from production site to performance/DR site which is separated by 100KM. We have a dedicated 2Gbit DWDM link for CA/XP. Is it feasible to use CA/XP for taking the initial copy i.e 30TB of DB size? If yes, what are the things need to be considered before doing this?
Note:
Array: XP12000
No sufficient tape library.
Thanks,
Srini

Re: First time DB copy using CA/XP

Srinikalyan — Wed, 04 Feb 2009 10:32:33 GMT

Can we do an initial copy of an P-VOL to S-VOL without an outage on the p-vol server?
Thanks,
Srini

Re: First time DB copy using CA/XP

Nigel Poulton — Wed, 04 Feb 2009 11:28:38 GMT

Is it feasible? That depends on your environment (DWDM utilisation etc etc etc)..

yes you can run a CA initial copy operation without an outage on the PVOL. However, if you are creating a synchronous CA pair, you will probably notice a performance impact on the PVOL server (writes are not acknowledged back to the host/app until the write is committed to cache at the SVOL end).

You may also want to think about the impact to the DWDM while you are shoving 30TB of data over it. You can throttle the pace of the initial copy operation by limiting the number of tracks copied at a time and if I rememer right, the CA software will only allow a certain number of LDEVs (may be 15) to be in initial copy at the same time (you can tell it pair up x amount of LDEVs but it will break them down so that no more than 15 are in COPY at the same time.

You will of course require 30TB of LDEVs at the SVOL end configured the same as at the PVOL end. E.g. if your PVOL side is comprised of 100GB LDEVs then you SVOL site will also have to be 100GB LDEVs. You may want to stagger the times at which you create each pair. For example create 5 TB per night for 6 nights. This really depends on how busy your pipe is.

Re: First time DB copy using CA/XP

Srinikalyan — Wed, 04 Feb 2009 11:42:03 GMT

Thanks Nigel for your suggestion.
-yes you can run a CA initial copy operation without an outage on the PVOL.
What happens if the update happens on the P-VOL while initial copying? will that the updated data be omitted or it will be copied anyway?
Note:
We are going to use CA Asynchronous Journal for the replication. So no much performance impact.

Thanks,
Srini

Re: First time DB copy using CA/XP

Nigel Poulton — Wed, 04 Feb 2009 11:59:04 GMT

All updates to the PVOL, while in COPY (initial copy) or PAIR will be copied to the SVOL. CA will not miss any updates.