3650 LACP etherchannel suspended

[adventurer]

This new 3650 series has been bugging me for the past year. Many things that used to work now doesn't.

Over last weekend I have upgraded a 3560X to a 3650. The etherchannel seems to behave differently in 3650.

Example,

interface Port-channel10
 switchport trunk allowed vlan 17,23
 switchport mode trunk

interface GigabitEthernet1/0/11
 switchport trunk allowed vlan 17,23
 switchport mode trunk
 channel-group 10 mode active

interface GigabitEthernet1/0/12
 switchport trunk allowed vlan 17,23
 switchport mode trunk
 channel-group 10 mode active

Now when this config is used in a 3560X and the end device is on standby (not communicating LACP) the ports goes into I - stand-alone state.

The same config is now put into a 3650, same scenario, and the ports goes into s - suspended state.

This may not seems to be a big issue, until I try to send WOL to the end device. In stand-alone state it will respond, but in s state effectively the line protocol is down (suspended), the WOL packet can't get there.

I'm really disappointed after one year going through versions 3.3.3 to 3.7.1, there are still funny issues with the 3650 series.

I hope someone is able to advise if they have any simple fix for this issue.

[Steve Fuller · Accepted solution]

Hi,

Add the command no port-channel standalone-disable on the port-channel interface and this should do what you want i.e., the member interface will go into Individual (I) rather than Suspended (s) state if it's not receiving LACPDU. You might need to bounce the port-channel interface for this to take effect though.

Take a read of the command in the Configuring LACP Standalone or Independent Mode section of the configuration guide for further details.

Regards

[adventurer]

You are a genius ! That's the solution.

[An Nguyen]

I have a similar problem.

Cisco router 2851 connecting to a stack pair 3750x.

The port channel doesn't form or stay up. It said LACP is not supported on remote port (the remote port being the 2851). Cisco doc shows that the built in Gig interfaces do support Etherchannel.

On the switch, when I configure g1/0/24 and g2/0/24 for mode on or desirable, I get a message saying command rejected, Pagp requires both ports to be on the same switch.

I am at lost now on how to achieve redundancy with the 2851 and the 3750X.

Thanks

[Steve Fuller]

Hi,

It's probably better to start a new post rather than add to an existing post that is not related, and that has already been answered as correct.

Anyway.

Can you post the configuration you’re trying to enter on both the router and the switch, and the error messages you get? That will help us understand the issue better.

You should also understand a number of points with respect to Link Aggregation on the ISR platform.

• The switch only supports Layer-3 EtherChannel on the integrated FE and GE interfaces.
• The message you got regarding Link Aggregation Control Protocol (LACP) not being supported on the ISR platform is correct. The platform supports Link Aggregation, what Cisco term as EtherChannel, but only a static form of link aggregation. The LACP is used on dynamic link aggregates as the control protocol to manage the LAG.

The white paper Understanding Layer3 EtherChannel Support on the Cisco Integrated Services Router discusses these points, and also has configuration examples.

Regards

[An Nguyen]

Thanks for the quick response.

So do I need to configure Layer 3 ports on the cross-stack switch?

int g1/0/22

 no switchport

int g2/0/22

 no switchport

int po22

 no switchport

int g1/0/22

 channel-group 22 mode on

int g2/0/22

 channel-group 22 mode on

And on the router,

int po1

no ip address

int g0/0

 channel-group 1

int g0/1

 channel-group 1

Do I have to shutdown int vlan 1 or not assign an IP address to int vlan 1 and assign an IP address to po22, the one I just created?

So does default gateway for the hosts now point to the switch's PO22 IP or the Router's?

Please advise.

Thanks

[Steve Fuller]

And what are the error messages you get when applying these configurations? Also what is the state of the interfaces after you apply the configuration? Are they operationally up, down or in some other state?

Regards
 

[An Nguyen]

I don't have that configuration in place now since the stack and router are in production.

I tried a few things last night and the Po interface never showed up but down (not connected all the time), the physical  interfaces on the switches show suspended.

I will try this new configuration and will post the result.

So do I use the po22's IP on the switch as default gateway for the hosts or do I still use the router's port-channel's IP as default gateway?

Thanks