Aaron Delp’s BladeVault

I had a chance to play with the IBM Blade Center Intelligent Pass-thru Module (IPM) on Friday. The device looks pretty slick, as long as you are using it in the right environment. We were told by IBM that the OPM (old 2GB max Optical Pass-thru Module) was going End of Life in January. So, being the good little Partner we are, we moved our customer to the IPM.

It turns out the IPM is a whole different beast. The OPM was a device that simply passed the optical signal from the expansion card on the blade to an external optical network or FC switch. This relationship was a one to one ratio.

The new IPM is basically a “dumb” Q-Logic FC switch that doesn’t participate in the FC fabric. It takes the 14 internal connections and pipes them through 6 external connections. The internal to external port mapping is configurable in the switch. The switch can also be upgraded (and downgraded back down) at any time to either a 10-port or 20-port FC switch.

All in all, it is a pretty slick set up but this approach does have down sides that the OPM didn’t have. First, the OPM had a one to one ratio (limited to 2GB speed) and second, the OPM can be used for Ethernet. The IPM has the advantage of 4GB speed and user configurable mapping of internal to external ports.

Our customer was using the OPM to pass Ethernet to Cisco switches so this wasn’t a good solution for them!! We made a few calls and it turns out we weren’t the only ones. IBM is now planning to continue production of the OPM for the near future.

Link to the IBM Redpaper on the IPM

This entry was posted on Sunday, February 10th, 2008 at 12:08 pm and is filed under IBM Blades, Q-Logic.You can follow any responses to this entry through the RSS 2.0 feed.You can leave a response, or trackback from your own site.