It may be a weird question, but I'm facing the following problem at the moment:
I've got a DELL PowerConnect 6248 Switch (managed Gigabit-Ethernet) with the YY741-Stacking module in the back. The module has two ports for CX4 10GBit.
However, I need to connect it via SFP+ to an existing switch. There are other modules for the PowerConnect 6248 which output e.g. SFP+ or RJ45, but is there a cheaper way by actually converting InfiniBand (CX4) to the desired SFP+ (e.g. using a transceiver)?
The CX4 ports are "Infiniband style" but still Ethernet (10GBASE-CX4). Media converters for CX4 to SFP+ are (were) available, but they're costly if you can still get them. Swapping the port modules or even buying a new switch may be more reasonable, especially with a cheap model (depending on your requirements).
10BASE-CX4 uses four lanes of 2.5 Gbit/s each (8b/10b-encoded, 3.125 GBd) while SFP+ requires single-lane, 64b/66b-encoded data (10.3125 GBd). Those cannot be simply adapted but require a transcoder chip - a low-volume item.
There are two Dell part numbers for stacking modules (UY108, YY741) plus the CX4 module (GM765) but only the latter is supposed to work in Bay 2. The switch can configure any module as Ethernet or Stacking via the CLI. Ethernet-configured ports will operate at 10 GBit and Stacking-configured ports will operate at 12 Gbit.
Supposedly it's possible to get 96 GBit throughput in a stack using all 4 stack ports on each switch in a double ring configuration. See the "Stacking Dell PowerConnect 6200 Series Switches" white paper.
