Ethernet channel on 02 switch 2960S

[Nam Nguyen Thanh]

Dear Team.

I have two switch 2960, WS-C2960S-24TS-L and WS-C2960S-48TS-L was stackable.

I was configured ethernet-channel, using one port on 2960S-24 port and other port on 2960S-48 port but not success.

After enter command channel-group 1 mode auto,

switch show error that it need two port belong to the same a switch.

Please help me solution?

Thanks.

[InayathUlla Sharieff]

Nam,

Few things I believe you have already checked:

1- Phycial interface is up

2- Before the etherchannel the port is up if directly connected between two switches.

3- Can you configure to use channel protocol or force that to on.

4- Give us the output of show etherchannel summary

HTH

Regards

Inayath

[Nam Nguyen Thanh]

Dear Team.

Yes, physical interface up.

On Stackable switch:

interface gi1/0/1

channel-group 1 mode auto

interface gi2/0/1

channel-group 1 mode auto

Stackable switch show error output, that it need port belong to the same a switch.

Thanks.

[Edison Ortiz]

Per documentation:

http://www.cisco.com/en/US/docs/switches/lan/catalyst2960/software/release/15.0_2_se/configuration/guide/swethchl.html

"

You can use PAgP only in single-switch EtherChannel configurations; PAgP cannot be enabled on cross-stack EtherChannels. "

Use LACP instead.

Regards,

[Nam Nguyen Thanh]

Dear Edison Ortiz.

It's mean, i need add more command below:

int gi1/0/1

channel-protocol lacp

channel-group 1 mode auto

on other port

int gi2/0/1

channel-protocol lacp

channel-group 1 mode auto

Thanks.

[InayathUlla Sharieff · Accepted solution]

Nam,

Try this

int gi1/0/1

channel-protocol lacp

channel-group 1 mode Active

on other port

int gi2/0/1

channel-protocol lacp

channel-group 1 mode Active

regards

Inayath

[Edison Ortiz · Accepted solution]

As I indicated before, PAgP does not support cross-stack etherchannel.

You are using PAgP with the 'auto' option.

Change the 'auto' option with 'passive' for LACP implementation.

Regards,

[Nam Nguyen Thanh]

Good solution.

Thanks Edison and Inayath.