NFS - ESXI experience DSM 3.0 with DS1010 or RS810?

[rs407]

Hi,
After reading the forum there seem to be issues with ISCSI and ESX (stability and/or performance).
Its also reports that NFS performance is lower than ISCSI even with "Async" option on the NFS volume.
NFS are the only supported protocoll according to Vmware HCL in RS810 and DS1010

My questions are:
1.Any production experiance of NFS and DSM 3.0 on the boxes above?
if yes:
2.How long have it been used in production?
3.Stability?
4.Performance?
5.Version of ESX/ESXI? (3.5,4.0 or 4.1)
6.Any "special" in the NAS config? (type of disk,volume/raid config)
7.Added extra RAM in synology?
8.Using DX510/RX410?

Thanks
/R

[miguel]

Ds1010+

1.Any production experiance of NFS and DSM 3.0 on the boxes above?
if yes:
2.How long have it been used in production?

about 3 weeks

3.Stability?

Unstable. I don't recommend it. If you simply try stop your vms, reboot the diskstation, the datastore in esxi will be unavailable and you'll have to remove and re-add it. I think this is somekind due to the nfs version used in DSM because noticied the same behaviour with rsync on nfs shares between other server and the diskstation. Mount point will respond with permission denied until you unmount it and re-mount. I don't get how Synology got nfs certification from Vmware sincerely..
I tried Iscsi (unsupported, altought my reseller told me it's certified..he said he has an e-mail mentioning it..) but I dumped it. sometimes vms stop responding and the datastore is gone.. The only way of getting it working again is to go the webpage and disable and re-enable iscsi


4.Performance?

Not as good as I see in other Nas we work with

5.Version of ESX/ESXI? (3.5,4.0 or 4.1)

4.1

6.Any "special" in the NAS config? (type of disk,volume/raid config)

Nope

7.Added extra RAM in synology?

Nope

8.Using DX510/RX410?

Nope

[jgallagher]

Miguel contact Synology support. They have a fix for the datastore missing or unavailable.

After that its stable.

I am working on benchmarking NFS speed I will have number soon for the RS810

esx 4.0

nothing added for my nas as far as ram. CPU and Ram seem fine in the default 810.

By the way I have contacted vmware support who went to the department who certifies devices. No certification for ISCSI only NFS.

Edit so far 45-50 MBps on ESX service console traffic.

[miguel]

"Miguel contact Synology support. They have a fix for the datastore missing or unavailable."

I've already contacted. Waiting for a response.. I still don't understand why I have to contact support to get nfs to work properly with vmware on an unit that's as the "Vmware Ready" sign.. At least this information should be public.

[jgallagher]

Tell them to refer to my case #54320

[miguel]

Hello,

They told me to upgrade to DSM3.1 beta. I'll not do it of course.. I replied mentioning your case

Thanks

[rs407]

Thanks miguel for the feedback.
It feels a bit strange that the oldest protocol (and implementation) NFS is that unstable.
VMware certification seems to be a simple test, not for durability or performance.
We have a other low-end NAS (non-synology) with Vmware certification for both ISCSI and NFS that have a NFS implementation so slow that it cant be used in practice.

But according to your experience synology isnt the first choise of low-end NAS for ESXI.

I know that ESXI 4.1 have change (improved) NFS
"NFS improvements
Using storage microbenchmarks, we observe that vSphere 4.1 NFS shows improvements in the range of 12–40% for Reads,
and improvements in the range of 32–124% for Writes, over 10GbE."

Do you used the "async flag" on the NFS share?

Please post your findings/resolution.

Edit 2011-03-30
Hi jgallagher, what kind of fix did you get from synology? I cant find any indication in the relese notes that NFS have been patched.
/R



/R

[jgallagher]

Just saw this post rs407, 3.1 fixes the timeout to esx when you reboot the synology. Before you had to re-add the synology every time due to the synology disconnecting.

I had a intrim .sh patch that fixed it before 3.1 came out

I found this after the fix which proabally would have helped. But it is nice that they fixed it.

http://miketrellosblog.arcadecab.com/20 ... on-reboot/

Also at some point I noticed that synology now has ext4 for the filesystem. This seems to be a good idea for vmware

http://blog.peacon.co.uk/file-system-ch ... fs-servers

I have had some delete or move big vmdks issues before with the synology 810. This may help it now. It wasnt a big issue before but a few timeouts here and there.

Another good article.
http://deinoscloud.wordpress.com/2010/1 ... atastores/

However I would trade a little perf loss with ext4 for stability.

Now how do we turn off the OPSlock on the synology to get some more perf?

EDIT *** just found out OPSlock as referred to the deinoscloud article is located in

Admin Menu\Network Services\Win/Mac OS, option labeled "Optimize CIFS database operations" as per this link.

viewtopic.php?f=106&t=3485

However not sure if it applies to NFS shares as the wording refers to CIFS.

[jgallagher]

One last article that is good for NFS

http://virtualgeek.typepad.com/virtual_ ... mware.html


As per your original question, I am happy with the speeds and stability now. Using iozone with a 8 gig file with sequential writes or reads at 32k I am maxing out my gig spees and around 120mbs read and write.

the nic is the bottle neck and not the drives or device. Im going to try to bond them since 3.1 allows you to.

[rs407]

Thanks jgallagher for the information.
Good to hear that the NFS are stable, it is after all certified against ESXI.

I will consider Synology next time we need low-end NFS storage to our ESXI.
NFS is still the prefeerd protcol over ISCSI on low-end due to the simplicity.
We have over 50 ISCSI and FC LUNs in our ESXI farm today but only two NFS shares, from both a admin and "storage" waste prespective thats a 25:1 advantage for NFS, regardless of I/O control for ISCSI.

If we will go the Synology trac for our low-end NFS storage we will use the extra RAM module and have 3 GB of RAM, just to get some extra "disk cache" and the fact that a "linux box" behaves stable and predictible as long as it have RAM memory. We use the same idea with extra RAM on our low-end ISCSI boxes (Promise Vessraid 1840I).

/R

[benedict]

Hi,

I just bought a DS1511+ as NFS datastore for ESXi 4.1 and I'm getting only 2-3 Mb/s transfer rate. I tried FTP to test the speed and it goes arounf 50 Mb/b. I just upgraded to the last DSM and I'm still getting those poor performances, any suggestion to help me?

Using FTP the drives are silent but with NFS they seem to do a lot of read/write.

Thanks

[jgallagher]

Enable async writes on the nfs share and you will see the 50s

[congo]

Enable async writes on the nfs share and you will see the 50s

please, would you provide indepth knowledge of this for the world? -maybe syntax to fstab or similar level stuff..

[jgallagher]

Just go to your NFS share on the synology in the DSM gui. Somewhere in the NFS settings where you defined map to root or in another NFS server setting page should be a checkbox to enable async writes on that NFS share.