I had an interesting experience yesterday working with a client who had a stack of 3 Avaya Ethernet Routing Switch 3549GTS-PWR+. The units were properly cabled but they wouldn’t stack with each other. In the past while working with the Avaya Ethernet Routing Switch 4000 or 5000 series you only needed to physically connect the stacking cables and power on the switches and they wouldstack together. You might have to check which switch was set to base using the dip/selector switch on the back of the switches, but there wasn’t much to it. I spent about 30 minutes fumbling with these switches until I stumbled across document NN47203-303 on Avaya’s support website.
It turns out that with the latest generation of switches from Avaya you need to manually enable “stacking” mode on the switches before they will stack. The ports on rear of the switch, usually associated with stacking, can be used as regular ports? Perhaps in a SPB type deployment?
I had to issue the following commands to all three switches;
>enable #config t #rear-ports mode stacking #save config #reboot
After making that configuration change to all three switches and rebooting them they finally all stacked together.
Learning something new every day!