By Michael Letschin, Field CTO
There was a time when Fibre Channel was the only solution for those looking for a high speed transport. But that is not the case anymore. The predominant storage protocol in many virtualization environments is NFS, primarily because virtualization administrators know that administering file-based datastores is much easier than those based on LUNs. In addition, advances in NFS and combining NFS with flash storage make the system’s performance ideal for hosting virtualized workloads.
But Nexenta is seeing a resurgence in customers expressing an interest in using NexentaStor’s Fibre Channel option. This is particularly interesting because, unlike other platforms, NexentaStor does not lock you into a particular protocol. Customers are free to choose NFS, SMB, Fibre Channel, or iSCSI. This means the only reason they would be using Fibre Channel is that it offers something that the other alternatives don’t – performance.
Performance is the main historical reason IT professionals prefer Fibre Channel over Ethernet; however, some may read that statement and disagree. Ethernet offers 40 Gb and Fibre Channel is only 16 Gb. If Ethernet has more bandwidth, how could Fibre Channel have better performance? The answer is bandwidth is not the primary performance consideration for some applications. If an application is looking for low latency, Fibre Channel will win over Ethernet almost every time. A look at the design of the two protocols will explain why.
Fibre Channel design assumes very short connections that are never longer than a Kilometer and usually much shorter. In contrast, Ethernet networks can stretch around the world. Due to this design difference, Fibre Channel can assume that all frames make it to the other side, where Ethernet assumes that many of them will not make it. This means Fibre Channel doesn’t have to do as much error checking and re-transmitting as Ethernet does. This translates into significantly lower latency numbers.
Another low latency device that is quite popular is Flash. Fibre Channel offers a better latency match to Flash than Ethernet does. Perhaps one has to look no further to see the reason behind this resurgence in Fibre Channel. If a customer has a latency-sensitive application, they are going to consider Flash as their storage medium. And if they are going to use Flash, they will want a low-latency protocol to communicate with their storage – and Fibre Channel meets the bill.
Whatever the reason for this particular resurgence in Fibre Channel, Nexenta’s solution allows customers to take advantage of whatever storage protocols they think are appropriate for their environment. And if they change their mind at a later date, they can start using a different protocol without changing their storage product. This is the flexibility of an open storage product like NexentaStor.
For additional information, read up on NexentaStor.