How to choose VMFS or NFS in vSphere5?

I am just confused about the technical difference and practical difference between VMFS and NFS.
For easy comparison, I assume the following.
(computer) box#1 and (computer) box#2 have same CPU, memory, same SCSI drives, same GigE NIC.
I  convert (by running some software) box#1 into a iSCSI SAN; box#2 into a NFS storage.
Now I also have 2 ESXi 5 hosts, called esxi-iscsi-host and esxi-nfs-host. Both have same hardware configuration.
Now esxi-iscsi-host connect to box#1 using iSCSI;
esxi-nfs-host connect to box#2 using NFS;
I also have identical typical virtual machines running on both hosts:
on esxi-iscsi-host:
dc11 (domain controller);
exch11 (Exchange server);
sql11 (Microsoft SQL server);
stream11 (Video streaming server)

on esxi-nfs-host:
dc21 (domain controller);
exch21 (Exchange server);
sql21 (Microsoft SQL server);
stream21 (Video streaming server)

Q#1. How will the dc11 compare to dc21 in terms of disk IO in the typical environment?
Q#2. How will the exch11 compare to exch21 in terms of disk IO in the typical environment?
Q#3. How will the sql11 compare to sql21 in terms of disk IO in the typical environment?
Q#4. How will the stream11 compare to stream21 in terms of disk IO in the typical environment?

Thanks a lot.
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
This topic has been an age old debate, which is fatest, better NFS versus iSCSI.

Many years ago, it was said by VMware, Fibre Channel was the best storage technology, followed by iSCSI, followed by NFS - something which is not necessarily true today.

Checkout this VMware Storage Protocol Performance document

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
It also does not matter which version of ESXi 3.5, 4.x, 5.0, its the storage protocol NFS versus iSCSI thats in question, if discussing performance, and no other features.

Other than performance you may want to consider if NFS has advantages over iSCSI.
I have not used NFS (just tested briefly), but I have read that it supports 'thin provisioning' for example.
So having more options on the storage side may have more flexibility benefits.
Powerful Yet Easy-to-Use Network Monitoring

Identify excessive bandwidth utilization or unexpected application traffic with SolarWinds Bandwidth Analyzer Pack.

richtreeAuthor Commented:
Thank you for your responses, especially the VMware storage protocol documents.
Do you think virtual streaming server perform similary inside iSCSI and NFS environment given ESXi has enough CPU power? This question is same as my original Q#4.
Aaron TomoskyDirector of Solutions ConsultingCommented:
I just ha this same question and set things up oth ways. Here are some of the lessons I learned:
With lower end gear (1 gb nic for LAN 1 gb nic for SAN, i7 whitebox machines) nfs and iscsi are the same speed.
With iscsi you can assign a 3rd nic to the same iscsi target and get more speed and redundancy if your target has multiple nics. With nfs you can't have anther nic to the same nfs share.
Nfs is easier to add to esxi, add storage, put in the ip ad share name. Done. Iscsi you have to add the target adapter and reboot. It also slows down the boot process.
Nfs you can connect to and copy vmdk files, iscsi you have to use a vm to connect in to read anything. Kinda funky.

Since there was no speed difference with my setup, I stuck with nfs. if you are goin to put multiple nics and bond them or get hba adapters then iscsi will go faster.
Andrew Hancock (VMware vExpert / EE MVE^2)VMware and Virtualization ConsultantCommented:
We've seen NFS out perform iSCSI and vice versa, it depends on your environment, the use of iSCSI Hardware Initiators.
richtreeAuthor Commented:
Thanks a lot.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.