HP Lefthand: Simple or Multi-Site cluster?

[GTMK]

Hello,

we have recently purchased a HP LeftHand P4500 G2 SAN consisting of 4 nodes to be placed in two sites which are approximately 200 m apart. I have still not made up mind whether of install them as an ordinary cluster or whether I should choose the multi-site setup. I assume that this decision will be hard to change afterwards.

The multi-site setup seems far more complicated - would that be worth the benefit of generally lower latencies? It is my feeling that the performance would not suffer too much from higher cross-site traffic and more switch/router hops but I don't have hard numbers. What about HA and FT in either scenario?

What are your recommendations and experiences?

Georg.

[dcoz]

A multi-site SAN is alot more complicated. You have to understand how HA will react in the event of link failure between sites, default gateway placement as well as the order in which you place the storage nodes to ensure you are mirroring the blocks between sites.

Multisite scenarios do work, but you really have to go through every aspect in detail before deploying.

Best thing to do is have a good look at the HP P4000 docs and understand what you are trying to achive by using multi-site.

Hope this helps

Dougie

[GTMK]

Thanks for your response. Unfortunately, I have posted my question a little alittle late. We started today to deploy the multi-site solution because the professional who performed the installation appeared to be quite experienced and recommended multi-site because of higher overall reliability. There will be sufficient time to do all kinds of failover tests before the SAN will go into production.

Nonetheless I am still interested in hearing from other LH users.

Georg.