Adding storage to VMWare ESXi host

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Dear Experts,

We are running one ESXi host with a mixture of live and test servers. Hardware is an HP DL360 G6 with 4 SAS drives.
Our aim is to purchase another server (DL380G6) to run another host ESXi server and a separate (preferably HP) storage unit to host the images and share them across both servers.
I have contacted our suppliers and have been recommended several different HP StorageWorks products, however they do not seem to be able to adequately explain the difference between the various types and whether we need DAS/NAS/SAN/iSCSI etc -what each type can achieve for us and ideally which one can also enable us to share storage amongst all servers on our LAN (not just virtual machine images)?

Thanks for your help
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Top Expert 2010
Well, each is going to achieve what you need; the first and more prominent difference among them is cost, based off the technology (Fibre is your most expensive technology). You can use them to host your VMs, as well as data. You can use it as data storage by connecting a LUN to a VM and using it as a volume as you would in a physical environment (i.e. File Server/shares) to use network drive mapping. I guess the first thing to decide is your goals & SLAs. Is performance a great concern (this has to do with not only the type of storage technology, but disk types used [SAS as opposed to SATA])? And what's your budget for implementation? Many variables to consider....

The NAS and SAN solutions will both provide the option for shared storage across the LAN and for Virtual machines.  The SAN is generally higher performance.
iSCSI and Fibre Channel are two methods of connecting to a SAN or NAS.  Fibre Channel is a long standing standard that is being replaced with iSCSI so either is still a valid choice.
For sharing between LAN servers and the VM guest storage, I would recommend the SAN with iSCSI solution personally.  The NAS is more for large file shares in my experience.
Top Expert 2014
Shared storage for VMware from HP you're probably looking at MSA2000 - you have 3 interface options; Fibre Channel - fast but expensive, iSCSI - slow but cheap, SAS - fast and cheap but limited to 4 hosts.

With only one host and now going for two it sounds like SAS attached may be a good option for you, so take a look at the MSA2000sa G2, the large form factor one has its own type of disk caddies but the smal form factor one takes the same disks that are in your current server (although should use dual ported ones as it has two controllers). The SAS HBAs to go in the servers (SC08Ge) are a lot cheaper than the F/C HBAs.

If you thnik you're going to need more than 4 servers you can start off with iSCSI instead, then if it's too slow replace the controllers with fibre channel ones, although the G3 has fc/iSCSI combo, loog at the G2 instead.

Alternatively a HP LeftHand P4000 could be used but for high availability you need two of them so gets a bit expensive.

If cash is a problem, then you can probably a serial attached SAN, such as a MSA2000sa.

It outperforms iSCSI, however you can only link 8 servers to it and they have to be close.

You get FC performance for a iSCSI price.

Top Expert 2014
Technically you can attach 8 hosts to a MSA2000sa but there are only 4 host ports per controller so the effective limit is 4 hosts if you want any form of high availability.
That is true, but you probably don't need that many servers, as there are 2 now. As well the fact that there are also test servers - for which you probably do not need High availability.

I would also get SAS disks for the SAN, as the HP SATA disks only have 1 year warranty. And SAS disks are also much faster, and expensive yes.
You can also access the MSA2000sa from other servers as well using a Serial attached HBA. How many servers do you want to connect to it?



Thanks for all the info.

As I see it, if we buy an MSA2000, it can do what we need - it all depends on the HBA we buy to go with it, so let me clarify, if we get a SAS HBA it only can connect directly to a max 4 servers, however if we get an iSCSI HBA or FC HBA we can connect to any number of servers on the LAN?

Although we only need to connect to 1 or 2 initially it would be helpful for expandibility if the storage could be utilised any other server.

Top Expert 2014
That's correct (although it's both the HBAs in the servers and the controllers in the MSA that have to match of course). You should be able to connect more servers via SAS as LSI logic have a SAS switch which would fan-out to 15 servers but it isn't a supported option from HP. It's probably the same SAS switch near enough that HP uses inside the blade enclosure (so you can connect two or more blade enclosures - 32 or more blade servers via SAS)

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