We've configured a head-end layer 3 switch and, downstream from it, an access switch (CatOS). The 2 ints (2/4 & 3/4) on the head-end switch are in an Etherchannel and the 2 corresponding ports on the access switch (2/4 & 3/4) form a trunk. The 2/4 int on the router is patched into 2/4 on the switch and the 3/4 is patched into the 3/4 on the switch.
This was working OK for awhile, but this morning we noticed the int 3/4 on the head-end switch was up/down and not in the channel. Yet, it's partner port 3/4 on the access switch is up/up. We verified the cables to make sure the two ports are patched to each other. The error msg we're seeing on the head-end switch is saying: " Te3/4 is not compatible with Te2/4 and will be suspended (trunk mode of Te3/4 is access, Te2/4 is trunk)"...Both ports on the head-end switch are configured identically. The only anomaly we found was that the vlans on the 2 ports forming the trunk on the access switch are not the same, but the native vlan is the same. Could that be the culprit here?
Thanks..
_ Greg
