Recover from misconfigured remote LACP channel

[jedavis]

So I am sure that I am not the only person that has done this.  I was staging some switches at a remote site and I removed a VLAN on 2 physical interfaces that were part of a LACP channel.  This of course caused a configuration mismatch between the physical interfaces and the port-channel interface and IOS suspended the channel.  The problem was that this channel was the uplink to the network and I lost connectivity.  

Is there any way to recover from this without physical access to the switch?   I think it would be possible if this were a static etherchannel rather than LACP or PAgP, because I think that at times in the past I have been enable to recover by disabling the channel on the upstream device.  I was lucky this time because it was a non-production device, but I have shot myself in the foot at least once on a production switch.  You all know that feeling, just after you hit enter and realize what you just did.......

Thanks!

-Jeff

[pieterh]

try shutting down the connected ports on the uplink switch (and maybe disable LACP here), then no shut only one,

no LACP channel should form and you can correct the misconfiguration?

[Cristian Matei]

Hi,

    In general the only safe net of the engineer is himself not screwing up. Don't get me wrong, maybe this is not the answer you were looking for, but i prefer to give an answer which works as opposed to one which may not work and cost you more in the end. With this specific example, based on the design of the network and the actual impact of that port channel being misconfigured, your problem may be way bigger that not being able to get access to the switches again, but a possible huge loop which may cause the whole remote network being "unreachable".

   If you ask me, i always recommend pay more attention before doing any changes, ensure you do things in the proper order of operation, try to have an easy life basically. What you can do is work with "reload in" option, for a remote device that you reconfigure, so that in case you loose access it reload with a working configuration. Don't save any configuration changes till you have confirmation that things still work and don't forget to cancel "reload in" after the changes have been verified and saved.

Regards,

Cristian Matei.