Issue with LACP configuration on Cisco Switch

[ray_stone]

Hello Experts,

I'm in process of creating a port channel in between Linux CentOS 6 ver. and Cisco Switch 4948 10 GE Model (Software Ver :bootflash:cat4500e-entservicesk9-mz.122-31.SG.bin) but having issues in configuring the same.

See the config below on switch:

Vlan 400

Int VLAN 400

IP address 10.1.16.1/23

Two interfaces added:

int range giga 1/27 - 30

switchport access vlan 400

switch mode access

channel-group 5 mode active

int Port-channel 5

switchport access VLAN 400

switchport mode access

when i run the command sh ip int brief then interface status shows up but protocol shows down and port channel status shows down of both interface and line protocol.

the following error is shown in logs:

3d08h: %EC-5-L3DONTBNDL2: Gi1/30 suspended: LACP currently not enabled on the remote port.

3d08h: %EC-5-L3DONTBNDL2: Gi1/27 suspended: LACP currently not enabled on the remote port.

3d08h: %EC-5-L3DONTBNDL2: Gi1/28 suspended: LACP currently not enabled on the remote port.

3d08h: %EC-5-L3DONTBNDL2: Gi1/29 suspended: LACP currently not enabled on the remote port.

when I run the following command on interfaces then both interfaces and port channel got operational:

int range giga 1/27 - 30

no channel-group

channel-group 5 mode on

After executing the above commands I can ping the connected linux server from switch which has four interfaces connected with switch port 27 to 30 and the IP address of the server is (10.1.16.17).

There is another VLAN configured on Switch VLAN 100 (10.1.12.1/23) and a client machine is connected on another port which is a part of VLAN 100. The IP routing is enable so client machine can ping it's own gateway and VLAN 400 gateway (10.1.16.1) w/o issue but this machine can't ping the server 10.1.16.17 even when I initiate the ping for gateway (10.1.16.1) from Server then it can ping but the VLAN 100 gateway (10.1.12.1/23) doesn't work.

Please provide your feedback on this and suggest the solution, if possible.

Thanks. 

[muca]

Hi Ray,

My guess is that the switch is running PAGP (Cisco Proprietary). Try to specify the LACP protocol and see if it makes any difference.

int range giga 1/27 - 30

channel-protocol lacp

[Reza Sharifi]

Hi Ray,

int range giga 1/27 - 30

switchport access vlan 400

switch mode access

channel-group 5 mode active

int Port-channel 5

switchport access VLAN 400

switchport mode access

by issuing the commands above, you have already correctly configured the switch side.  You also need to configure the Linux server with LACP in order for the portchannel to come up.

HTH

[Julio Carvajal]

Hello Ray,

Basically the CentOS is not configured to negotiate the Port-Channel so when you try to run a negotiation protocol to bring the port up (In this case LACP) is not going to work as the other end needs to be LACP aware (either active or passive).

How to fix this is basically configuring the other side (CentOS 6.x to run LACP) or use ON  on the switch side so no negotiation is done.

Now regarding the ICMP problem

1. Can you ping the server from the Switch itself
2. Can you check the Firewall iptable and make sure that´s allowed on the server

Check my blog at http:laguiadelnetworking.com for further information.

Cheers,

Julio Carvajal Segura

[Ashfaq Ahmad]

Hi,

you need to enable the LACP on physical port which are member of EtherChannel;
let's say i have interface port-channel 10 and physical port member of this port channel is interface gigabitEthernet 0/0, so i need to go to interface gigabitEthernet 0/0 and apply the command " channel-protocol lacp " and then make it member of port channel.

int gigabitEthernet 0/0
channel-protocol lacp
channel-group 10 mode active