The 2nd installment of an occasional feature . . .
A reader writes:

I think your input would be valuable in helping me make a decision on storage for my company. I’ve done loads of research and I’m fairly certain I have good players narrowed down, but have reservations about both. . . .

-Datacore SANMelody H/A solution on HP hardware.
-Equallogic PS3800XV

The app
It’s is an up-to-the-minute commercial application supporting virtual machines. The VM’s run proprietary messaging/transactional servers that spend 99% of their disk I/O time appending very small messages – ~300 bytes – to transaction logs.

Update: After the initial comments, the prefers-to-remain-anonymous reader (BTW, I did check him out and his company is for real) added this clarification:

  • Yes, there are DR and HA requirements.
  • Each VM has its own transaction logs that can grow to GBs in size. These transaction logs are not for archival purposes, rather to recover state in the event of an application restart
  • Traffic: Traffic will come in bursts and maximize at about 1500 iops between 10 separate hosts.
  • Reservations: Is Equallogic a “true” H/A solution considering it does not support synchronous replication between completely separate hardware? Are the competitors claims of Datacore’s “unprotected cache” well-founded? (Datacore insists in H/A mode that all cache is synchronously written and requires a commit from its H/A partner before committing to client.)
  • Storage size requirements are small, so I’ll pay for SAS performance over SATA terabytes.

End update.

Update II: The anonymous reader comes back with more crucial detail:

Let’s pretend the budget is around $60k-$70k. I know the two finalists can provide an acceptable degree of HA, DR, and iSCSI performance at that price. What products should one be looking at from HDS/EMC/NetApp? They were not considered initially for the perception of being unaffordable.

End update II.

Update III:

The plan is for an H/A setup in a class 1 datacenter with asynchronous replication over an existing DS3 (..but dark fiber is in the works) to a remote site.

All things considered, the question could be framed, “Whom/What should be demanded for trial?”

End update III.

The StorageMojo take
It is interesting that this customer is NOT looking at the traditional OLTP storage vendors. This is a business-critical application – the company is handling Other People’s Money.

What are the questions the reader should be asking of vendors? How should the problem be framed? I surmise that price is an issue. Where else might the reader go?

I welcome comment from vendors, but please do us the courtesy of identifying yourself as such.

Comments welcome, of course.