LACP and LAG Phantom Issue

[techinneed]

Hello all,

Need a little help here.

I have a switchport interface in a port-channel group.  Currently the physcial switchport is not taking any errors, no CRCs, input errors or link status changes.  When I look at the results from a "show interface et1/1", all the values above are zero.

Here is my issue, when I do a "show log", it states the following multiple times:

Lag: %LAG-MEMBER_REMOVED

Lag: %LAG-MEMBER_ADDED

Both entries have the same datetimestamp.

Can someone explain what could cause these multiple bounces?

Thank you!

[Reza Sharifi]

Can you post the config from both sides of the Portchannel?

HTH

[techinneed]

I do not have the config for the other side as it belongs to a client.

interface po1

   load-interval 5

   ip address 1.1.1.1 255.255.255.252

   spanning-tree bpdufilter enable

interface et1/1

   load-interval 5

   no switchport

   channel-group 1 mode active

   no lldp transmit

   no lldp receive

Hope this helps!

Thank you!

[julian.bendix]

Hey,

what kind of switch do we have here (Model)?
Is this a nexus switch?

Can you post the output of "#show logg | i 1/1"?

Is Et1/1 the only member of the Port-Channel?
If no, please also post the config of the other member ports.

In general it is not a good idea to have the config of the Port-Channel Interface and the physical Interface differentiating like that (in order to not get confused like that).
Try to configure as much as possible from the Port-Channel Interface without touching the physical ones anymore, after setting up the channel.

[techinneed]

Cisco Catalyst 9300 Series

switch1 %EC-5-UNBUNDLE Interface Et1/1 has left Port-Channel1

switch1 %EC-5-BUNDLE: Interface Et1/1 has joined Port-Channel1

Yes, Et1/1 is the only interface in the port-channel

I do not understand your statement below:

"In general it is not a good idea to have the config of the Port-Channel Interface and the physical Interface differentiating like that (in order to not get confused like that). >>> What is differentiating that is causing confusion?

Try to configure as much as possible from the Port-Channel Interface without touching the physical ones anymore, after setting up the channel. >>> I do not think I added anything peculiar on either interface"

My config on Et1/1 is generic and the only config I added was "channel-group 1 mode active"

Do you know what may cause this "leaving\joining" the port-channel?

[Reza Sharifi]

Can you try and rebuild the Portchannel again?

delete po1

no po1

inte e1/1

no  channel-group 1

now rebuild it 

inte e1/1

channel-group 1 mode active

above command will create po1 for you.

now go to po1 and ip

int po1

p address 1.1.1.1 255.255.255.252

no sh

verify with command

show etherchannel 1 summary

can you ping 1.1.1.2 if the other side is configured correctly?

HTH