Problem connecting to cabletron switch

[omohatarem]

I'm trying to connect a cisco cat 4006 w/L3 module, to a cabletron switch (5000 i believe). the problem is, as soon as i plug in the LAN cable, the cabeltron freaks out and pretty much grinds to a halt. has anyone had this problem before when connecting to a cabletron?

[j-block]

It sounds like you are creating a loop and all ports are remaining in forwarding mode. Have you setup STP? http://www.cisco.com/warp/public/473/5.html