etherchannel between WS-C4506-E and stacked WS-C2960S-48LPS-L

[Alexander Kluge-Wolf]

Hello,

we are having a "suspend" issue to portchannels with 2960S switches only.

On our core switch we have the following setup:

interface Port-channel68
 description EC DELEJ02SAC88
 switchport
 switchport trunk allowed vlan 6,7,10-12,19-21,30,63
 switchport mode trunk
 

and the two ports are:

interface GigabitEthernet1/3/10
 description SAC88
 switchport trunk allowed vlan 6,7,10-12,19-21,30,63
 switchport mode trunk
 logging event link-status
 udld port aggressive
 channel-group 68 mode active

!
interface GigabitEthernet2/3/10
 description ECM DELEJ02SAC88-D20
 switchport trunk allowed vlan 6,7,10-12,19-21,30,63
 switchport mode trunk
 logging event link-status
 udld port aggressive
 channel-group 68 mode active

On the other end we have a stacked 2960s with two switches.

Ports are configured as this:

interface Port-channel1
 description Uplink Core
 switchport trunk allowed vlan 6,7,19,21
 switchport mode trunk

and the two stack ports (one of each switch):

!
interface GigabitEthernet1/0/49
 description Uplink Core/Chassis1
 switchport trunk allowed vlan 6,7,19,21
 switchport mode trunk
 udld port aggressive
 mls qos trust dscp
 channel-group 1 mode active

and

interface GigabitEthernet2/0/49
 description Uplink Core/Chassis2
 switchport trunk allowed vlan 6,7,19,21
 switchport mode trunk
 udld port aggressive
 mls qos trust dscp
 channel-group 1 mode active

Same configuration we do have on our not stacked 2960 and is working fine. But here we have one port in supended state:

Group  Port-channel  Protocol    Ports
------+-------------+-----------+-----------------------------------------------
1      Po1(SU)         LACP      Gi1/0/49(P) Gi2/0/49(s)

We don't have anything in the logs.

Do anybody came across with this issue or having nay idea how to fix it?

Many thanks in advance

@Lex

[glen.grant]

   Verify your ports are correct , you have different descr on the 4500 on the ports so i would verify they go where you think.  Trace them and or use CDP to verify they go where you think .  Config looks ok though i would match the allowed vlans on both sides to keep it consistent.  Look in the logs also , it usually gives an indication why it is suspending the ports.

[Filip Po]

I met similiar problem on C4500.

Try to remove etherchannel configuration by taking ports to it's defaults and also interface Port-channel68.

Then create port channel interface by first issuing :

interface GigabitEthernet1/3/10
 description SAC88
 channel-group 68 mode active

!

interface GigabitEthernet2/3/10

  description ECM DELEJ02SAC88-D20
  channel-group 68 mode active

Then configure all stuff around switchport under interface Port-channel68.

[Alexander Kluge-Wolf]

Hi guys,

thanks for quick respond. CDP neigh allready checked, connected to the right ports.

I will try removing / adding port channel on core but have to wait getting a time window from site.

THX

[Filip Po]

Did you get it worked?