Connecting a new switch in via fibre
Morning my fellow heroes of EduGeek... I'm afraid I come crawling for assistance again as I am feeling thoroughly stumped at this juncture.
I've bought a load of 3Com 2928-HPWR switches to let us plug in some PoE WAPs, and I'm trying to connect the switches to the network via fibre uplinks. For whatever reason, though, the switches utterly refuse to actually connect to the network :(
I know all the physical gear is ok - after many combinations of SFP transceivers, patch cables and other switches - and the only common link is the new switch(es). Somewhere in the configuration (I imagine) is something that is stopping the fibre uplink from working properly.
As I look at the switch back in my main server room (that this fibre run goes to) - if I plug the SFP module I'm using into any of my current switches, the port shows up as active on said server room switch and everything is dandy. As soon as I plug the fibre module into the new switch, it shows as inactive. I've compared and contrasted settings across the different (but all 3Com) switches and everything seems the same. The manual is no use whatsoever. The switch is otherwise working (transmitting power, I am logged into it via web interface on a laptop). Just something, somewhere, is stopping the switches actually talking to each other. It lights up this end on the new switch, but never flashes for activity, and the other end never lights up at all.
This is getting excessively frustrating now, it's starting to take the :censored: somewhat. So I beg of you fellow geekers - any advice? Any clues? Anything incredibly obvious I have so far missed?