NFSv4.1 Webcast Q&A

Our recent Webcast: NFSv4.1 – Plan for a Smooth Migration was very well received and well attended. We thank everyone who was able to make the live event. For those of you who couldn’t make it, it’s now available on demand. Check it out here.

There wasn’t enough time to respond to all of the questions during the Webcast, so we have consolidated answers to all of them in this blog post from the presentation team. Feel free to comment and provide your input.

Q. Will NFS 4.2 be any easier to migrate to than 4.1? Would it be worth waiting for?

A. NFSv4.2 is a set of additional functionality that will be easy to take advantage of – if you’re on NFSv4.1. The first move is to NFSv4.1, as it offers a wealth of features over and above NFSv3. Waiting for NFSv4.2 features wouldn’t be advisable; it’s unlikely to be ratified until the end of 2012, and enterprise server solutions and the required downstream client distributions will be a lot further out than that.

Q. Since NFS 4.1 is out, what is the uptake in the industry?

A. There aren’t any global figures, since not all suppliers collect detailed information about protocol usage, and of those that do, many can’t differentiate between NFS versions. Anecdotally, it’s slow. That’s because NFSv4.1 servers (particularly for file-layout) have only been available for less than a year, and the needed Linux client support has only recently made it through to the enterprise distributions.. NFSv4 (as opposed to 4.1) is more widely used; but the only figures I have are anecdotal, and would be misleading.
Q. Are there any network architecture design considerations that need to be taken before implementing NFSv4.1?

A. No. In fact, (if you’re not using pNFS) NFSv4.1 should get you more “bang for your buck” as there’s a reduction in network traffic compared with NFSv3. pNFS requires a different architecture; your storage vendor should be able to assist in the planning.

Q. Clustered servers – you mentioned that vendors had to provide a special server for this… are these enhancements going to be ported into the general linux nfs server stream?

A. I’m not sure to what this refers; perhaps the MDS (metadata server)? Although this server is often shown as a separate box in diagrams for simplicity, that’s not how it is normally implemented. The MDS is normally part of the cluster running on one or more fo the data servers.

Q. If you recommend AD for kerberos, do all of the NFS clients need to be joined to the same AD domain as well? Or only the servers?

A. Any time a client in one domain (or realm) attempts to access a server, the server must be in the same realm as the client, or if it’s in another realm, there must be cross realm trust so that the principal (the client) can be correctly authenticated.

Q. Can you talk about any difficulties in using Active Directory with NFS? Are there changes needed on AD?

A. No changes are needed to AD. It’s relatively straightforward security administration, and storage vendors should be able to provide you with implementation checklists.

Q. What is the impact on clustering and failover by introducing statefulness?

A. Significant! And much better. Recovery is much improved, as the server and client after a failure can attempt to agree on what locks were held, what files were open, what data had been written and so on. It’s a big improvement on NFSv3.

Q. Will it be possible to mount root file systems from NFSV4? Like boot from the SAN that we already have in FC or iSCSI?

A. Yes, that doesn’t change.

Q. Can you explain the reasons why home dir and hpc would benefit with v4.1?

A. Home directories are an easy win; no application (well, at least that you care about) and easily migrated. The same is often true of HPC. For example where the data is transient – served from a store to local disk, computed and crunched, and then sent back to the store – the store could be migrated to NFSv4 and the app later; or the app first and the store later.

SNIA Highlights NVM Programming TWG at Intel Developers Forum

SNIA is proud to participate at the Intel Developers Forum this week at Moscone West In San Francisco.  Our booth in the NVM Express Community area focuses on SNIA and SSSI work in non volatile memory.

Attendees are very interested in the newly launched SNIA NVM Programming Technical Work Group (NVMp TWG).

The purpose of the NVMp TWG is to create specifications which will provide guidance to operating system, device driver, and application developers to be able to accelerate the availability of hardware-enabling Non-Volatile Memory (NVM) software.  A concrete example is database software which can use NVM to assure the database is available quickly after a system reboot.

The TWG will develop two specifications. The first is for NVM Extensions between OS Components. The work on a first version is starting now with an expected completion of about Q4’12.  The second specification is for NVM Application Extensions; with the first version expected Q2’13.

The Solid State Storage Initiative (SSSI) will  provide marketing and outreach support to the NVMp TWG, extending its educational mission.

The NVMp TWG is supported by EMC, Fusion-io, HP, Intel (also chairs the TWG), LSI, NetApp, Oracle, Samsung, SanDisk, Seagate, Symantec, Toshiba, Virident, and VMware.  More companies are in the process of joining SNIA and the SSSI.

If you are interested in the NVMp TWG, and/or want more information on SSSI activities  visit www.snia.org/forums/sssi

Flash Webcast – Are You Ready for the Disruption?

There’s no doubt that flash is a game changer. Even a relatively small percentage of flash can drive a significant improvement in peak storage performance. How are you planning for the disruption? Join me and my SNIA colleague, Paul Feresten, for a live Webcast next week, Thursday, September 20th (11:00 a.m. ET, 8:00 am. PT) as we discuss the impact of flash. We’ll take a look at how flash is being deployed in storage systems, key considerations and tradeoffs, performance benefits, trends in non-volatile memory and more. And because it’s live we’ll take your questions on the spot. We hope to see you there. Register now.

Solid State A Winner at Flash Memory Summit

SNIA Solid State Storage Initiative (SSSI) enjoyed a lively following at the recent Flash Memory Summit in Santa Clara CA.

PCIe SSD was a favorite topic.  A Tuesday Chat with the Experts found SSSI members Eden Kim (PCIe Flash), Paul Wassenberg (SATA Express), and Jim Pappas (Solid State Storage Standards) speaking to full tables.  A SSSI-sponsored PCIe SSD panel on Thursday moderated by Eden Kim of Calypso Systems included talks on PCIe performance testing, SATA Express, PCIe 2.5 form factor, SCSI Express, and PCIe and Storage Class Memory.  The SSSI booth was packed with individuals and companies eager to learn more about our PCIe SSD, NVM programming, and workload I/O capture program activities.

Solid state technology dominated sessions and the show floor.  SSSI Marketing Chair Tom Coughlin of Coughlin Associates gives his technology perspective of the show in his Storage Bytes blog for Forbes at http://blogs.forbes.com/tomcoughlin/.  Check it out and let us know your thoughts!