We have 8 PowerConnect 5548 switches and are interested in using the HDMI stacking for 10GbE.
We currently have all 8 switches powered on and running production traffic on them. Each switch is currently either "home run'd" back to a Cisco switch, or daisy-chained to another PowerConnect 5548 that is.
The HDMI technology wroks great for stacking the PowerConnect 55xx series. You can only use the HDMI ports on the 55xx for stacking though and not for uplinking to a Cisco or other device. Also you can only stack 55xx switches with other 55xx and running the same version of firmware.
On the 55xx, you don't need to reboot the switches, but just plug in the cables to create the stack. An algorithm is used to determine which member becomes master, and wich members become slaves. I believe the master is determined by which switch has been powered up the longest. Just remember that if you have the switches in different subnets or vlans, they're configurations will now be changed since all switches will become as one large switch.
The type of HDMI cable is important, you will need to refer to the documentation that came with the switch, or you can download the User Guide at http://support.dell.com. You will need cables that provide throughput of 10.2 Gbps (max. allowed by HDMI specification). Usually the cheaper cables do not provide this.
According to the DOC, the switches requires a HDMI 1.3a or above cable. I tried a 1.3c cable. It shows connected properly but the traffic across the swtich is very very bad~~.. So you have solid experience that stacking via HDMI is stable?
I know this is an old thread now but in an attempt to provide some closure on this thread please read on:
I tried what was thought to be a 'high quality' HDMI cable, by high quality I mean it was more expensive than the Dell HDMI cable and the fact that the company's specifications stated the 3m HDMI v1.4 cable would carry 10Gbps, but the third party cable failed dismally!
I proved it was the third party cable as I had a Dell 1m HDMI cable included with the switch, which I used to stack the two Dell PC55xx switches and the throughtput was as expected.
(*I must note that the Dell HDMI stacking cable is thicker than the third party "high quality" HDMI cable.)
Subsequently, I have since purchased a Dell 3m HDMI stacking cable and the PC5524 and PC5548P stacked switches operate perfectly.
To avoid any mucking around, I simply suggest that for anyone considering HDMI stacking with the Dell PC55xx series of switches that you buy the Dell HDMI cable.
Thx David, I didn't update this thread. Finally we solve the problem by replacing the HDMI cables.