iSCSI/Nas

kj0

Hi All. Hope all are doing well and keeping to your resolutions, so far.

I'm currently reading through the storage section of Mastering vSphere 5.5 and writing up a post for my blog and I have come across a question I asked myself a while ago when I was using OpenFiler as my "SAN" for my LAB. I don't remember reading it when I was reading Mastering vSphere 5. and I can't find much online, but, what is the take on using NFS on a NAS connected to vSphere instead of iSCSI (Providing the NAS has iSCSI capabilities)??

IN the book, it only talks about NAS and NFS as a relationship, but nothing about using the iSCSI on the NAS. Now, I know in most business cases you would use a proper SAN over a NAS for your production, but If either cost or just to keep the price down on a dev infrastructure (Which I would assume you wouldn't do, so you can try and keep it identical to your production) was the case, would you use NFS over iSCSI?

We have multiple NAS' around our business, we use NFS to connect our deploy Studio Mac server to the repository and we use iSCSI to leverage MS iSCSI Initiator so we can use AD security groups for folders. So I haven't had to have them touch vSphere.


This is just a hypothetical question.

Thanks

EV42TMAN

Granted I could be looking at this wrong, but i was always under the impression that(Generally) iSCSI was for block based access and nfs was for File based access. So with that in mind you couldn't use NFS over iSCSI unless you created an iSCSI lun, added it to ESXi, and deployed a server OS that can be a NFS server. That way it would technically be "NFS over iSCSI" but it would really be, you and an iSCSI SAN and you deployed an NFS VM. When I took my current job a year ago we use ESXi and iSCSI SANs to host our infrastructure. At that time I wanted to get more familiar with ESXi and iSCSI so I just bought an Synology NAS and made it an iSCSI Target and connected to an extra computer I had running esxi

emerald_octane

Back in the day you wouldn't dream of deploying NFS for production VMs. You only connected it as a datastore for ISOs, imgs and such. Now, the performance is such that it really doesn't matter for lower end environments. Obviously you can't do things such as (true) iSCSI Multipathing with NFS but you can achieve some redundancies.

Ask your vendor for best guidance. For instance, NetApp users may prefer NFS.

SimonD.

We are a large NetApp house (170+ Filers) and went down the NFS route for our initial vCloud deployment but discovered that performance just didn't meet our expectations. Add to that issues we were seeing with locking and a move to iSCSI was on the books for us sooner than we originally thought.

The move to iSCSI for us improved our deployment times and removed the lockout issues we were experiencing, various tests were carried out and the improvements for us definitely warranted the change to iSCSI.

I did some testing on various home based NAS solutions (OpenFiler, OpenDSS, Iomega IX4-200d) that showed that actually for the most part iSCSI was a better performing choice when compared to NFS, there were some exceptions to the rule (Open-E DSS NFS performance just rocked when I did it back then, I haven't tested it recently tho).

Home Lab NAS/SAN Shoot-Out Part 1 « Everything Virtual
Home Lab NAS/SAN Shoot-Out Part 2 « Everything Virtual

I would suggest testing for yourselves to see what kind of performance differences you experience when moving from NFS to iSCSI but I wouldn't be surprised if for the most part you do see an improvement.