ESXi 4 and Windows NFS

[peedy]

Does ESXi 4 work any better with any windows based nfs server? Built in or SFU 3.5?

thanks,

chris

[Schorschi]

Sure. I have used SFU 3.5 on Windows 2003 and Windows 2008 support NAS for ESX and ESXi 3.5 Update 4 or 4.0. The issue is performance, Windows based NFS is not as good as straight Unbuntu, Fedora, or even RHEL 5.3 based NAS via NFS. Windows SFU is ok, but not great. I would never implement production on NAS based on Windows SFU.

[peedy]

What kind of performance did you get when using SFU or Built in NFS in 2003 R2? Also is there a 3rd party nfs server for windows you would recommend?

[Schorschi]

In the past, since it was in a lab context, just to validate NAS/NFS functionality in ESX, we did not benchmark it per se. Our production then was EMC SAN based, and we expected NetApp based production in the future. So while we were evaluating iSCSI, and had a NAS network configured in the lab, we did the Windows NFS setup just because we could.

Recently, i had Windows 2008 wth SFU setup as well as, Ubuntu, Fedora and then RHEL 5.3 serving NFS for NAS for ESXi, and Ubuntu was the fastest. RHEL, Fedora also bet Windows NFS hands down. It was obvious so we discontinued Windows SFU NFS. On the same hardware, where all we changed was the OS and NFS implementation in that OS, Windows NFS served VMs, loading Windows 2008, the difference was strikingly apparent on the write operations, where Windows 2008 installer is expanding files. Again,we did not bench mark it, since the difference was so obvious.

[DSTAVERT]

I did see somewhere in a VMware document that NFS on Windows wasn't recommended as a datastore. It is also far too easy to implement on LINUX to even consider Windows. A LINUX export file doesn't need to be anymore complex than a single line. Where I have used it is to install the Windows client to assess the NFS shares on LINUX.

[RParker]

VMware document that NFS on Windows wasn't recommended as a datastore

Using windows for ANY type of server is generally a bad idea.. It's great for services / hosting but NOT for any type of storage, File Storage, NFS, iSCSI, or any backend storage Windows is a FAIL!

You will get much better efficiency as you say.. with Linux, I agree.

[DSTAVERT]

In case someone from VMware is watching RParkers comment could be extended to " windows for ANY type of server or virtualization platform is generally a bad idea"

[Schorschi]

OOOOHHHHHHHH! That was just TOO easy!

[peedy]

While your comment may have some merit, I as a consultant have a duty to fulfill my customer needs. That means working within the environment and condition they may or may not have. Im clear that NFS on a unix box is better. But that doesn't exactly answer my question.

[DSTAVERT]

If the customer is asking does it work. Yes. Is it recommended. I will try and find the reference but I was pretty sure the document from VMware's perspective was that it wasn't recommended. If the question is which is better Windows 2008 or 2003? 2008. If the question is Addon or Windows storage server??? The bottom like is performance is poor. Does the customer wants to be convinced that they should choose Windows as an NFS platform?

[peedy]

No essentially the customer is saying please make our already purchased and in production windows based SAN/NAS work for our VM datastore.

[DSTAVERT]

Then you get to prepare them for poor performance or use local storage for OS partitions and use the Windows device as it was intended, for file shares.

[Dave_Mishchenko]

The post by Paul here describes the root problem should you have performance issues. Are you able to enable iSCSI on the Windows server?

[Schorschi]

Thanks for the thread on the performance, but writes were not that bad, just not as good as Linux distros (various) on same hardware. Maybe we dodged a bullet? WIndows was not as slow or as bad as the thread discusses, if memory serves, just not better than Linux. So we stopped using Windows based NAS/NFS performance in the lab only because we had better options, the entire NAS testing at the time, for NFS was really a sanity check against our iSCSI testing, on AX150 series devices. Since our production was all FC based, even the iSCSI work on AX150 series was all lab evaluation work.

As for iSCSI on Windows, yes we did it as well. You have to hack things a bit, since we wanted to use the Windows iSCSI target not a 3rd party. Windows support for, or I should say Microsoft support, on Windows for an iSCSI target is part of Windows Storage Server, and you can Google for details on that. A few people have used Windows 2003 WDS evaluation media to do this. Microsoft has an evaluation of Windows Storage Server that is good for 90 or 120 days as I recall, and buried in WDS is an iSCSI target tool, but this hack is not recommended by Microsoft, they of course want you to purchase WDS.

We also did iSCSI on Linux (on Ubuntu 8.04 and Fedora 10 and recently 11) and again, we saw the noticable delta on same hardware between Windows and Linux. Microsoft is completely geared to SMB for network transport of data from a file system perspective, and iSCSI as NFS has to suffer as a service based entity, whereas, integrated to the Windows kernel SCSI supports are FC or DASD focused, so our expecations where that Windows as NAS will never be identical to Linux nor supercede Linux. WIndows Core may change this scenario to degree, since some of the Windows overhead that Linux avoids is removed. We have not tested WIndows for NAS on Windows 2008 Core yet. As long as Microsoft is indifferent or declines NAS support for Hyper-V? Does anyone expect Microsoft to change the kernel architecture to improve NAS performance?

[Mr_Gimper]

Is it worth you looking at the StarWind iSCSI Target, available from here

Gets favourable reviews, and the company are a vmware technology alliance partner.

G

[Schorschi]

Since the customer just wants it to happen? I would not use SFU under any circumstances, that leaves you with WDS or 3rd Party solution, neither is free of course. StarWind would appear to be a significant option for iSCSI. I don't see any great difference between NFS or iSCSI based on my experience on Windows. But both rely on the network design and switch infrastrcture. I would strongly suggest you isolate your storage traffic from other traffic, this includes dedicated NICs, portgroups and vSwitches on the ESX host side as well. VLAN tagging works but without proper packet priortization at the network side, you can expect some interesting issues and quirks. We VMs have significat writes to complete, or VM snapping is being done, especially snapshot consolidation, expect some issues, you are absorbing bandwidth. Even in a FC based environment, such write intense operations impact over all performance that is visible to the customer with in the VMs.