April 30th, 2013
In this third and final blog post on NFS (see previous blog posts Why NFSv4.1 and pNFS are Better than NFSv3 Could Ever Be and The Advantages of NFSv4.1) I’ll cover pNFS (parallel NFS), an optional feature of NFSv4.1 that improves the bandwidth available for NFS protocol access, and some of the proposed features of NFSv4.2 – some of which are already implemented in commercially available servers, but will be standardized with the ratification of NFSv4.2 (for details, see the IETF NFSv4.2 draft documents).
Finally, I’ll point out where you can get NFSv4.1 clients with support for pNFS … Read the rest
April 18th, 2013
Seamus Crehan, President, Crehan Research Inc.
2012 turned out be another very strong growth year for 10 Gigabit Ethernet (10GbE), with the data center switch market and the server-class adapter and LAN-on-Motherboard (LOM) market both growing more than 50%. Broad long-term trends such as virtualization, convergence, data center network traffic growth, cloud deployments, and price declines were helped further by more specific demand drivers, many of which materialized in the latter half of 2012. These included the adoption of Romley servers, expanded 10GBASE-T product offerings for both switches and servers, 10GbE LOM solutions for volume rack servers (which … Read the rest
April 15th, 2013
Storage traffic running over Ethernet-based networks has been around for as long as we have had Ethernet-based networks. Of course sometimes it is technically not accurate to think of the protocols as fundamentally Ethernet protocols – whilst FCoE, by definition, only runs on Ethernet, iSCSI, SMB, and NFS, they are, in reality, IP-based storage protocols and whilst most commonly run on Ethernet, could run on any network that supports IP. That notwithstanding, it is increasingly important to understand the real nature of Ethernet, and in particular, the nature of the new enhancements that we put under the umbrella of Data … Read the rest
March 21st, 2013
Red Hat Enterprise Linux shipped their first commercially supported parallel NFS client on February 21st. The Red Hat ecosystem can deploy pNFS with the confidence of engineering, test, and long-term support of the industry standard protocol.
Red Hat Engineering has been working with the upstream community and several SNIA ESF member companies to backport code and test interoperability with RHEL6. This release supports all IO functions in pNFS, including Direct IO. Direct IO support is required for KVM virtualization, as well as to support the leading databases. Shared workloads and Big Data have performance and capacity requirements … Read the rest
March 13th, 2013
I’ve gotten some interesting feedback on my recent 10GBASE-T blog, “How is 10GBASE-T Being Adopted and Deployed.” It’s prompted us at the ESF to learn more about your 10BASE-T plans. Please let us know by taking our 3-question poll. I’ll share the results in a future blog post.
March 5th, 2013
A challenge with traditional iSCSI deployments is the non-deterministic nature of Ethernet networks. When Ethernet networks only carried non-storage traffic, lost data packets where not a big issue as they would get retransmitted. However; as we layered storage traffic over Ethernet, lost data packets became a “no no” as storage traffic is not as forgiving as non-storage traffic and data retransmissions introduced I/O delays which are unacceptable to storage traffic. In addition, traditional Ethernet also had no mechanism to assign priorities to classes of I/O.
Therefore a new solution was needed. Short of creating a separate Ethernet network to handle … Read the rest
February 26th, 2013
The completion of a specification for FCoE (T11 FC-BB-5, 2009) held great promise for unifying storage and LAN over a unified Ethernet network, and now we are seeing the benefits. With FCoE, Fibre Channel protocol frames are encapsulated in Ethernet packets. To achieve the high reliability and “lossless” characteristics of Fibre Channel, Ethernet itself has been enhanced by a series of IEEE 802.1 specifications collectively known as Data Center Bridging (DCB). DCB is now widely supported in enterprise-class Ethernet switches. Several major switch vendors also support the capability known as Fibre Channel Forwarding (FCF) which can de-encapsulate /encapsulate the Fibre … Read the rest
February 19th, 2013
In a previous blog post Why NFSv4.1 and pNFS are Better than NFSv3 Could Ever Be, some of the issues with NFSv3 that made it difficult to implement as a WAN based or data center wide protocol were discussed. The question then becomes; why not move to NFSv4 instead of NFSv4.1? Isn’t that a bigger leap from NFSv3?
Well, practical experience and some issues with NFSv4 made NFSv4.1 a necessity; for one, it introduces the key concept of sessions, and provides a foundation for pNFS (parallel NFS) which we’ll discuss in a later blog post. And all the features … Read the rest
January 31st, 2013
I guess this is a blog that could either be very short or very long… The full name of the protocol – Data Center Bridging capability eXchange (DCBX) basically tells you all you need to know or maybe nothing at all. At its simplest, DCBX does what it says on the tin and the way it is in effect used is no more or less than the DCB auto negotiation capability to make sure that the data center network is correctly and consistently configured. It is important to note that technically you can debate if this is an auto negotiation … Read the rest
January 14th, 2013
A significant challenge in managing large amounts of data (or Big Data) is a lack of what I like to call “total data awareness”. It’s a situation where you know (or suspect) that you have data – you just can’t find it. When you think about many current IT environments, they are often not built for total data awareness. This starts with core elements of the IT infrastructure, such as file systems. Traditional file systems and access methods were not designed to store hundreds of millions or billions of files in a single namespace. This leads to admins storing … Read the rest