Friday, October 28, 2011

Storage MBps Performance Concepts

We recently had a reader post a question about the other aspect of storage performance – MBps. In most cases my clients are concerned with IOPS more so than transfer rate so it doesn’t come up that often. When it does it normally gets back to economics, applications such as streaming video, audio or even backups tend to be sequential and require a lot of capacity. As with IOPS the higher RPM drives tend to outperform the lower RPM drives but the difference in not nearly as substantial as it is with IOPS.


Monday, October 24, 2011

Cisco MDS switch interoperability with Brocade Access Gateway and Qlogic Adapters

During a recent SAN switch migration from McData directors to Cisco MDS 9509 switches, I came across two interoperability issues. The first issue involves certain Qlogic adapters connected to the Cisco MDS switches where the area portion of the Fiber Channel ID (FCID) is the same for the initiator and target. The second issue has to do with internal routing in the Brocade 4Gb switches running in "Access Gateway" mode. In my case the Brocades were embedded in blade chassis, but they could be stand alone. Note, the 8Gb version of the Brocade switches did not exhibit the routing issue.