Last week I wrote an article on IT environments that chose Network File System (NFS) for their shared VMware storage, and at least one large IT shop corroborates my story. An IT administrator at a well-known investment management firm writes that he runs 45 VMware ESX 3.0.2 hosts that run more than 1,000 VMs entirely on Network Appliance network-attached storage (NAS) 3070 boxes — and with great success.
“We haven’t seen any issue with speed, that is for sure,” he writes.
Before switching to NetApp, the firm ran its environment on EMC and Hitachi storage area networks (SANs). The admin described the latter as “a pain,” “expensive,” and suffering from SCSI lock, manageability and host bus adapter (HBA) issues.
By moving to NetApp NAS, the firm has also realized another benefit: improved data protection. “We also love the fact that we save a lot of money on the backup solution. We just use snaps to another NetApp — no agents, no tapes, no overpaid workers, no maintenance contracts on over 1,000 servers.”
Bless its heart, NetApp also chimed in on the article, taking umbrage at statements made by Fairway Consulting Group CEO James Price. About a year ago, NetApp began testing NFS for VMware at the behest of customers looking for more manageable storage but who were worried about the ability of NAS and NFS to scale. What they found is that “NFS is robust enough to run production environments,” said Vaughn Stewart, virtualization evangelist with the company. In the coming months, NetApp plans to publish results of tests performed in conjunction with VMware.
At the same time, NetApp is working with VMware to get the company on board with NetApp’s “NFS is good” message. As it stands, “VMware is inconsistent throughout its documentation about the role of NFS,” said Phil Brotherton, NetApp senior director of enterprise solutions. It may be a tall order, as the storage community has a strong bias in favor of Fibre Channel SANs.
But in Brotherton’s view, some of that preference is a bit self-serving. “A lot of people are trained on a technology, and that’s a good reason to be biased toward it,” he said, adding that many shops have sunk a lot of money into existing Fibre Channel infrastructure. “But I also see a lot of people try to spin technical arguments to justify what is really a sunken cost argument. . . . I would love to see the discussion move past performance to why people are really using NFS; performance is not the issue.”
When it comes to displacing SAN with NFS, our nameless IT administrator echoed Brotherton’s opinion. “I can tell you that you there are some old-school SAN guys (myself included) that are scared that they might not be needed as much as they think. It is becoming easier and easier to use NFS for most everything. There are certain cases where a SAN is needed, but it is not necessary for every case.”