topic Re: XP512 vs EVA5000 in Disk Enclosures

XP512 vs EVA5000

Dave La Mar — Thu, 20 Jan 2005 16:50:17 GMT

We currently have an XP512 and, for financial reasons concerning additional storage, we are now looking at replacing our XP with an EVA5000.

Though all comments are welcome, I would especially like to hear some pros and cons on the EVA5000, in regards to an XP replacement, from those of you that have worked with (or currently have) both.

Points to be assigned at thread closing.

Best regards,

dl

Re: XP512 vs EVA5000

Ian Vaughan — Fri, 21 Jan 2005 04:37:18 GMT

Howdy,
Big question is - do you have applications that need lots of cache at the array end? i.e. reporting type applications or are you in an OLTP environment. You can put lots of cache in a XP whereas the the EVA is based on a "virtualization" approach where you just let the array get on with it.
In either case you'll want to have a look at the quickspecs and sit down with an HP reseller who knows what he/she is talking about. These things are too much money to just choose it from a website.
An EVA5000 will probably give you at least as much performance as your XP512 does but of course it depends upon your environment and how well it is set up. The EVA's are certainly a lot easier to manage as you can do most of the operations yourself through the Command View interface. If you have any specific questions please ask.
ttfn
Ian

Re: XP512 vs EVA5000

Zinky — Fri, 21 Jan 2005 08:49:59 GMT

We have both the XP512 and EVA 5000s. I would say 2 EVA5000's will roughly equal the performance of an XP512. We have never experienced any problems with the XP512 for the last 4+ years whilst the EVA5000 - even if easier and speedier, we've had problems with it and is not conducive to being a "single array solution".

EVA 5000's can fail but they should still be viable enterprise storage solutions if proerly implemented. By proper implementation - I mean use some form of failover or mirroring (ie. VxVM mirroring) accross at least 2 EVAs so your protected. With VxVM - you can have the ability to mirror and do snapshots accross the 2 EVAs as opposed to EVA BusinessCopy which only do snapshots within a single EVA.

If cost is really an issue.. then 2 EVA5000's (or even 2 XP128s or EVA 3000s) should be a good value proposition.

Re: XP512 vs EVA5000

Ian Vaughan — Fri, 21 Jan 2005 11:14:45 GMT

Forgot to say...
The EVA 5000 & 3000 are only just getting to the stage where you can do "hot" (should really be "warm") firmware updates on the controller VCS firmware. Prior to VCS 30.20 IIRC the controllers needed to reboot after any upgrade. If you have a very high uptime requirement this could be an issue.
HTH
Ian

Re: XP512 vs EVA5000

Dave La Mar — Fri, 21 Jan 2005 11:53:04 GMT

Ian -
We have had a very detailed presentation on the EVA 5000 from the reseller with HP present.
On the cache issue, their claim is that the logic in the EVA applies cache to array luns as required while removing cache from low activity luns. Thus, "they say", this offsets the additional cache the XP512 has. The majority of the applications are Oracle with little OLTP. I believe we were told, hot swap ablility and hot firmware updates are available, but I will verify.
Nelson -
Your comment, "we've had problems with it and is not conducive to being a "single array solution", is of grave concern. Our fabric is extremely redundant, but there has been no consideration of a second EVA for failover. This was supposed to be a "High Availability" solution as the XP has been for us. If 2 EVA's are required for the same value of "High Availabilty", then the cost factor negates an EVA solution. Incidentally, we will be using the Snapshot (Cloning) option as we currently Business Copy 1.75 tb in it's entirety daily.
I would like to hear more on your - "we've had problems with it and is not conducive to being a "single array solution" - comment.

Great input from both, and thank you.

Regards,
dl

Re: XP512 vs EVA5000

Zinky — Mon, 24 Jan 2005 09:40:20 GMT

Dave,

Yes we did have a couple of problems with our EVA5000's (purchased in the last 18 months) that ranged in disruption from a few minutes to one that lasted nearly a day - with some loss of data on one outage! These failures have been attributed to bad drive firmware or VCS code or simply "load related". ALL of our EVA5Ks are HP-UX connected and subjected to very very high loads. We use BusinessCopy/EVA to do snapshot/snapclones as fallback but since the copy/snapshot resides on the SAME EVA as your production - ALL YOUR DATA will be unavailable if your lone EVA Fails. IF you've two EVAs - you can use LVM or VxVM mirroring to mitigate the risks and provide HA uptime or use the more expensive solution - called Continous Access/EVA - which is not really a mirroring solution but rather a DR solution.

If your environment is Windows, Tru64 or OpenVMS - then the EVA's should be a right fit as I've never gone accross any failures of EVA's hooked up to those environments. Which makes me suspect that the EVAs were really meant for those environments to begin with -- being a Compaq (DEC) product that was inherited by HP...

Go with the XP if your environment needs predictive scalability and performance and uptime out of a single array solution. Longer term - it will actually come out cheaper than most IT ROI formulas will indicate.

Re: XP512 vs EVA5000

Dave La Mar — Fri, 28 Jan 2005 14:33:11 GMT

Back to the top.
I would hope there are more opinions out there.
I will be closing this thread on 02/02 unless there is sufficient response to justify keeping it open longer.

Thanks to the Ian and Nelson for contributions thus far.

Regards,

dl

Re: XP512 vs EVA5000

Dave La Mar — Wed, 02 Feb 2005 16:28:03 GMT

Points were awarded for the relevance of the input as well as the value.
A bit disappointed in the number of responses, possibly should have cross posted, but I abhor doing that.
Ian and Nelson, thank you for taking the time to share your insights.

I sincerely hope we are making the right decision since the EVA purchase appears to be a forgone conclusion.

dl