VMware solution - SAN advice, what storage solution?

The MSA2000 is normally from SMBs and your hardware can handle something more robust.  Take a look at the HP EVA (costly but good) or NetApp (provides NFS (may be close to performance as iSCSI), FC, Snapmanager for VI (quick restores for VMs)

Thanks for your advice guys.

@demazter: I did look at lefthand stuff, but I could only see the iSCSI stuff, and after looking at this http://www.vmware.com/files/pdf/perf_vsphere_storage_protocols.pdf I became convinced that FC was the way to go. Is there a lefthand FC option?

@paulsolov: Maybe you are right. I was looking at the MSA because I have a limited budget (about 5 -6 k GBP excluding disks). I guess I could just use server storage this year, and get a decent SAN in the next round of funding (next year).

Take a look a the NetApp, you may be able to use NFS or iSCSI for now and upgrade to FC later.  The EVA is nice but from my memory you could only add fully filled shelves.  The NetApp can scale with mixed SAS, FC, SAS drives and snapmanager for VI, SQL, Exchange can be used to make your life easier.  Also provides good SAN to SAN replication as an option down the road.

In leu of 8GB FC you may try 10GB Nics with iSCSI or software initiator, from reading up on vSphere the load on a typical ESX host for software initiator is very minute, especially with 6 cores.  You could also use a 10GB nic directly using NFS (since there's no encapsulation it's faster than iSCSI in most instances)

If you just want cheap you can use a iSCSI MSA2012i with SAS drives for under $8K US$ for around 4TB if you find a good deal.  It could be cheaper then getting the FC HBAs by themselves.

Are you discounting iSCSI because of that article?

I have actaully seen the lefthand in operation and an equivilent FC solution and there is very little differnce!  Remember the disks are all transfering data at the same rate so the connectivity method doesn't make a great deal of difference (in my opinion)

the benefit if the left hand solution is because if thecway it is structured you can keep adding to it and increasing your egficiency and tolerence levels.

With the virtualisation solution you are actually getting 2 SAN's mirrored (very expensive if you go the FC route) then if you add another you are in effect RAID5'ing (not sure if that's a proper word or not) your SAN.  The more you add the more tolerant it becomes and the more spindles you are using which improves performance.

If your budget is so low, you should forgo 8GB FC and I think 4GB FC may still be too expensive for your budget.  ISCSI is definitely a good solution. We personally don't use it as we have FC. But ISCSI is not bad.

If you look at the roadmap of technology, you get FCoE (fiber channel over ethernet) and you already have 10GB products out - so if you actually do manage to max out your ISCSI network, it's just a matter of buying 10GB switch and cards.. Of course I know FCoE is not ISCSI, I'm just saying 10GB ISCSI is there too right now!

Also look at this solution SanMelody (www.datacore.com) It supports FC, ISCSI, etc. We use it for our dual redundant FC SAN.

>The EVA is nice but from my memory you could only add fully filled shelves

Nope, there's a PSU limit meaning you have to have a few disks per enclosure but they don't have to be full, the only real limit is minimum 8 disks per disk group, you can even have mis-matched disk sizes although it isn't recommended for performance reasons.

I'd go for DL380 G6 rather than DL580 G5, just compare the VMmark results - http://www.vmware.com/products/vmmark/results.html

I'd strongly recommend aganist RAID 6, it has 6 physical I/Os per logical write as opposed to two physical I/Os per logical write of RAID 10, so is much slower especially with random I/O where write cache isn't so much use.

How may servers are you going to have in total? Four or less and you could use MSA2000sa G2, SAS connect is cheaper and faster than 8Gb fc or 10Gb iSCSI. More than 4 servers and you might as well use blades, again you can use SAS attached since you can have 2 full enclosures attached to a MSA2000sa through blade SAS switches. (Not that the bandwidth of the bus matters since you're very unlikely to have 4Gb worth of disk performance anyway).

Get in touch with NetApp - we just went through a similar exercise and got a FAS2020 with some disks on NFS for inside your £6k budget. There are some new models out soon and due to the recession the sales guys are making some very good deals.

Alternatively as suggested by paulsolov look at the HP EVA - these are good as you can actually buy the base model for very little and just add disks to scale up sine your hardware will kill anything smaller.

20,000 iops for an EVA4400, 17,700 for a MSA2024; hardly any difference. Hardly surprising since both were tested with same number of disks (96). I doubt you'll get much difference using a FAS2020. I'd recommend running the HP VMware ESX sizing tool, it obviously won't recommend a FAS2020 but it'll configure the correct number of disks for both MSA2000 and EVA4400 based on your I/O input requirements.

Thanks for all the input everyone. I'm very grateful.

It's not so much the speed advantage of FC, but the reduced latency that got my attention. I am now convinced that it's probably not within my budget. SAS is looking good as an alternative.

@andyalder: Are those VMark results actually compatible? (ESX v3.5u2 vs v4, 24 cores v 8) I get the feeling that the the 580 with E7450 chips in it would fare better. There are also VMware licensing benefits to 6 core processors, and the ability to add two more processors later on to take into account. I don't see this site needing more than three of the above servers in the next 3-5 (which ties in with vCenter foundation licensing), so blades don't seem to make much sense. It's interesting that you don't like RAID6. I had heard good things, but maybe I need to do some more research. I didn't know a bout the sizing tool, thanks for the tip. I'm downloading it now :-)


@paulsolov, eabeukes: I'm liking the look of the netapp offerings. I saw a FAS2020 3TB BUNDLE for about 8K GBP on froogle, I'm sure with a bit of hunting I can find it for less.

The Netapp can go one further in that it is able to do multi-protocol serving ie CIFS/SMB/SMB2 for Windows file shares (replacing a MS license and CALS), NFS for UNIX and VMware shares and FC/iSCSI for SAN. There are also all the benefits of using ONTAP so you can hold onto those skills for the future.

That price on Froogle is still quite high - like I said, get in touch with them and they'll make you a deal. It's all the rage now

6*500GB? You'll not take long to decide to throw them away and replace with 15K disks.