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New Member

%EC-5-CANNOT_BUNDLE2: - Etherchannel wierdness or BUG???


Has anyone come across such a problem where:

- after a power outage to a building, the port channel between the distribution switch and the edge switch unbundles.

- note, that the configuration on both ends of the uplink are identical as far as:

o Speed, duplex,

o Spanning tree port cost, priority, portfast

o jabber frames

o trunked vlans, native vlan & trunk mode as shown below:

Distribution Switch & Edge Switch


interface Port-channel8

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 1-499,600-799

switchport mode trunk

interface GigabitEthernet1/0/17

switchport trunk encapsulation dot1q

switchport trunk allowed vlan 1-499,600-799

switchport mode trunk

channel-group 8 mode on

spanning-tree portfast disable

However, after a power outage, in some cases we find that the ether-channel unbundles, with the following syslog message:

Aug 31 12:02:54 clay-28-402-rk1-fes1 33332: Aug 31 12:02:52: %EC-5-CANNOT_BUNDLE2: Gi2/0/24 is not compatible with Gi1/0/24 and will be suspended (trunk mode of Gi2/0/24 is dynamic, Gi1/0/24 is trunk) (clay-28-402-rk1-fes1-2)

...when the configs haven't been changed at all.

After changing cables, etc, the only thing that brings things back to normal is a power cycle of the distribution and edge switches.

Seem to think that it is a bug with ether-channels with this version of IOS:





Re: %EC-5-CANNOT_BUNDLE2: - Etherchannel wierdness or BUG???

We saw this on a different piece of equipment this morning , fix was to pull the port channel config and then reinstall it , so I would consider it a bug .

New Member

Re: %EC-5-CANNOT_BUNDLE2: - Etherchannel wierdness or BUG???

I'm glad, that at least someone else has experienced the same issue with this version of IOS!

Cisco Employee

%EC-5-CANNOT_BUNDLE2: - Etherchannel wierdness or BUG???

Thanks a lot.... Glen.Grant  Even I experienced the same issue and it got fixed after I removed and pasted again the port channel configuration

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