Configure Etherchannel / LACP between Cisco Router and Cisco Switch?

Hello all! I currently have a conondrum between a Cisco router and Cisco switch. I have a Cisco 2911, and a Cisco 3650-X that I would like to configure link aggregation between.

I am very familiar with configuring etherchannel on Cisco switches. However, I have not configured LACP between a switch and a router. The router interfaces I am using are gi0/1 and gi0/2 which are both routed interfaces. They do not support switchport commands. I have tried a few port channel commands and LACP related commands but cannot get the aggregation to work properly.

Does anyone have experience doing this? And if so, could you provide a config snippet of the interfaces on the router and switch that are aggregated? It'd be a huge help. Thanks!

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Comments

networker050184

A quick google says its supported on the on board interfaces. What have you tried so far?

Corndork2

I know! After googling around and looking at some cisco documents this is the configuration I have so far:

2911 Configuration:

interface Port-channel1
description LAN LACP
ip address 192.168.16.1 255.255.255.0
hold-queue 150 in
!
interface GigabitEthernet0/1
description LACP to Switch
no ip address
duplex full
speed 1000
channel-group 1
!
interface GigabitEthernet0/2
description LACP to Switch
no ip address
duplex full
speed 1000
channel-group 1

3650-X Configuration:
interface Port-channel1
description LAN LACP
switchport mode access
!
!
interface GigabitEthernet0/47
description LAN LACP
switchport mode access
speed 1000
duplex full
spanning-tree portfast
channel-group 1 mode passive
!
interface GigabitEthernet0/48
description LAN LACP
switchport mode access
speed 1000

But Im still seeing:

*Mar 6 21:31:03.075: %SW_MATM-4-MACFLAP_NOTIF: Host 70ca.9be5.44a1 in vlan 1 is flapping between port Gi0/47 and port Gi0/48

So something cant be right?

networker050184

Looks like PAgP and LACP are not supported on the ISR. You would have to do mode on on the switches.

keenon

its doable, i have it setup on a 3800 going to a hp switch.

Corndork2

Mode on the switches? What exactly are you referring to?

I have mode set to passive on the 3560 Switch now. Passive should only try to establish a link when it detects an LACP association upstream. Should I set it to active?

networker050184

Passive or active will not work as the router does not support LACP or PAgP. You should use channel-group 1 mode on.

nice343

on the switches for mode you on.

routers do not support negotiations for ether-channel unless you are doing it from a switch module...

Corndork2

keenon wrote: »

its doable, i have it setup on a 3800 going to a hp switch.

What does your config look like? Do you mind posting it?

networker050184

Have you tried setting mode to on? What this does is make a static etherchannel which you are going to need in this scenario.

Corndork2

Testing the "Mode on" reccomendation now. Config on both devices is:

2911 Router Configuration:

interface Port-channel1
description LAN LACP
ip address 192.168.16.1 255.255.255.0
hold-queue 150 in
!
interface GigabitEthernet0/1
description LAN LACP
no ip address
duplex full
speed 1000
channel-group 1
!
interface GigabitEthernet0/2
description LAN LACP
no ip address
duplex full
speed 1000
channel-group 1
3650-X Switch Configuration:
interface Port-channel1
description LAN LACP
switchport mode access
!
!
interface GigabitEthernet0/47
description LAN LACP
switchport mode access
speed 1000
duplex full
spanning-tree portfast
channel-group 1 mode on
!
interface GigabitEthernet0/48
description LAN LACP
switchport mode access
speed 1000
spanning-tree portfast
channel-group 1 mode on

Corndork2

Thanks everyone!

Changing the switchport interface commands to "channel-group 1 mode on" solved the problem.

Thanks again!

mrjcsh

Are you using packet tracer? Packet tracer seems to be limited in command capability by design. This would encourage consumer behavior in renting rack space with cisco for the intended purpose of obtaining ccnp without employment.

Wow, I really dug up a dead one, didn't I!?