topic Host based mirroring with an XP and an EVA in Disk Enclosures

Host based mirroring with an XP and an EVA

Rick vonR — Tue, 21 Jul 2009 17:58:18 GMT

I want to do host based LVM mirroring using two different types of storage. The LUNs would come from an XP12000 and an EVA8400. The XP has 2x16 port 2Gb cards, and 146GB 10K FC drives. The EVA8400 has 4Gb connections, 300GB 15K FC drives, and 22GB cache. The SAN is 4Gb.
This is for a DRLite (Disaster Recovery Lite) scenario. I.e. The XP is in one building on the campus and the EVA is in another building. There is one pair of HP-UX servers and one pair of AIX servers using VCS. The server pairs are split between the two buildings. A set of XP LUNs are given to the HP-UX servers and LVM mirrored to a set of EVA LUNs. Same with the AIX servers using a different set of LUNs.
What I want to know is if this is a workable solution? Are there any compatibility or performance issues that I need to be concerned about? Are there any documents or white papers for this type of setup? I was thinking about having the LUNs from each type of storage come into different HBAs on the servers.

Re: Host based mirroring with an XP and an EVA

Greybeard — Thu, 23 Jul 2009 12:20:34 GMT

so long as the LUNs used are matched and configured on the Host software the main issues are likely to be back end array performance and physical data path throughput, any mims-match can lead to a performance hit and a loss of synch, which if it gets too bad could corrupt data, I would suggest some performance testing on the pathways to each back end before implementing.

Re: Host based mirroring with an XP and an EVA

Rick vonR — Thu, 23 Jul 2009 15:30:34 GMT

Thanks Larry,
I will be testing a lot with my current slower hardware (8100 vs 8400). I will have to assume that any performance issues I get will be less with the newer hardware. Frankly, I'm more concerned about the XP keeping up with the 8400. 8-)

I had also posted this question in the LVM forum and wrote a much longer response if you would care to read and comment. Points still assigned.

http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1357584