Step-by-step EtherChannel between CatOS and IOS?

To have the switches use PAgP you need to set the mode to either auto or desirable. Try the following and see if you have better luck with it.

set port channel 4/20-21 mode desirable

channel-group 1 mode desirable

Hope this helps,

-Dan

Chris wrote:

Thanks Dan. Before I read your post I had them both set to "on", and it

% show channel info

(snip)

That's from the 4006's CatOS. I'm not sure what the equivalent command is in IOS?

Chris

This should be reasonably straightforward. One thing that can easily happen during the configuration of port channels if the ports are up connected is that ports can be put in the errdisable state. On IOS shut then no shut the port to recover.

that is it.

when you issue these commands a new interface will be created

int port-channel 1.

I think that Cisco recommend mode desireable since the kit can recover from various possibly problematic problems in that case.

One thing that can cause problems is that if trunking is configured the two ends must agree on which VLANS are to be transported.

To get it working you could disable trunking on both ends and then turn it on afterwards.

Make sure that you have logging enabled

IOS

log buffered deb log buffered 50000

CatOS - I forget - sorry, been a while.

There are probably some debugs on the IOS end.

opswhq02#deb etherChannel ? all All debugging detail Step below all error Displaying error messages event Major events idb Agport idb related events linecard SCP messages to linecard

opswhq02#deb etherChannel

WARNING - you need to take care with debugs on production equipment due to potential CPU overhead however I would think that this one would

be quite safe. Playing with etherchannel on production equipment on the

other hand is not at all safe due to the possibility of network loops forming, fapping etherchannels triggering STP re-convergence.

Try "show etherchannel summary" That should give you what you're looking for. Just be aware that you're not using PAgP the way you have it setup, but if you're just looking for a working etherchannel you should be good to go.

Here's sample output from the show etherchannel summary.

rmpx4#sh eth s Flags: D - down P - in port-channel I - stand-alone s - suspended H - Hot-standby (LACP only) R - Layer3 S - Layer2 U - in use f - failed to allocate aggregator

Number of channel-groups in use: 1 Number of aggregators: 1

Group Port-channel Protocol Ports

------+-------------+-----------+-----------------------------------------------

-Dan

Chris wrote: