Removing port from channel-group

[emily00001]

I've run into an odd issue with port aggregation where I decided to remove a port from a port channel and put it into another but in my SNMP tool it still belongs to the old port channel and the new simultaneously.

The port channel was created by using:

(config)#interface gigabitEthernet 1/0/22

(config-if)#switchport mode trunk           

(config-if)#channel-group 1 mode active

And then changed through

(config)#interface gigabitEthernet 1/0/22    

(config-if)#no channel-group 1 mode active
(config-if)#channel-group 2 mode active

I also get this when I pull information on etherchannel.

#show interfaces gigabitEthernet 1/0/22 etherchannel 

Port state    = Up Mstr Assoc In-Bndl 

Channel group = 2           Mode = Active          Gcchange = -

Port-channel  = Po2         GC   =   -             Pseudo port-channel = Po2

Port index    = 0           Load = 0x00            Protocol =   LACP

Flags:  S - Device is sending Slow LACPDUs   F - Device is sending fast LACPDUs.

        A - Device is in active mode.        P - Device is in passive mode.

Local information:

                            LACP port     Admin     Oper    Port        Port

Port      Flags   State     Priority      Key       Key     Number      State

Gi1/0/22  SA      bndl      32768         0x2       0x2     0x117       0x3D  

Partner's information:

                  LACP port                        Admin  Oper   Port    Port

Port      Flags   Priority  Dev ID          Age    key    Key    Number  State

Gi1/0/22  SA      32768     0817.35e4.2c80  26s    0x0    0x2    0x118   0x3D  

Age of the port in the current state: 164d:21h:32m:44s

Could this be an issue with my snmp tool (observium) or are there any additional steps for removing a port from a channel-group? Switch restart?

System image file is "flash:c2960s-universalk9-mz.150-2.SE4.bin"

[Jose Solano · Accepted solution]

Hi,

I would say that this is related to the snmp tool, once you remove the port from the previous channel and added to the new it will belong to that one only, there is no way that an interface will below to 2 different port channels.

Also there is no need to restart the switch or anything like that, you can use the following commands to confirm that the interface is now part of the new channel group:

Show etherchannel summary 

Show run interface gi1/0/22

With those commands you will see that the interface belongs to channel group 2, and the command you attached above shows that the interface belongs to po2.

Hope this helps

[emily00001]

Thanks Leo,

This does seem most plausible. I did try removing the switch and rrd-data from observium although this did not change the report of double port-channel membership when device was added again. When I have more time I will try moving it to another snmp tool to see if it changes.

Marking your answer as correct as it is the most likely explanation although I haven't yet verified it.