I recently install a 4006 switch as my core switch. Everything is fine except for one thing. I got a 3661 router and when I connect (fast ethernet 0/0) it to one of the gigabit port it says that the port is connected but I couldnt ping the router. It comes up for about 5 minutes then drop.
In fact this router is the default gateway of the switch. I have connected a 1751 router and a 2522 router to this switch and it works fine.
Is there anything that I should enable on the switch end ?
