Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Need help about etherchannel and vlan configuration

Hi all,

I had a 2821 cisco router with a lot of vlans on a same interface. This is a Wan router, each vlan is connected to a trunk to my ISP and directly connected to a SDSL oneacces ONE60 modem. I want to replace 2 one 60 in the same location by a 1801 router with 2 WIC-SHDSL-V2 card. Each car can support 4MBit/s on 2 pairs. I want to do etherchannel between vlan 0/3/1.501 and 0/3/1.502 on my 2821 wan router and on this other side between the 2 WIC to obtain a 8MBit/s throuput.

I try to do :

interface Port-channel2
description VPN-2x4MBit/s
ip address
duplex full
hold-queue 0 in

A part of my conf contains :

interface FastEthernet0/3/1.501
description SDSL-4M-VPN-Lien01
encapsulation dot1Q 501
interface FastEthernet0/3/1.502
description SDSL-4M-VPN-Lien02
encapsulation dot1Q 502

But if I try to add the commande to one of my vlan interface : channel-group 2 mode active

I had channel-group2 on all my vlan shared the same interface.

Do you see an issue ?

Best Regards.


Everyone's tags (1)

Re: Need help about etherchannel and vlan configuration

That is correct - that is what will happen, all sub-interfaces under the acutal interface will be placed into the EtherChannel.

AFAIK you cannot place individual virtual interfaces into seperate etherchannels, it's based on physical layer 2/layer 3 interfaces.

New Member

Re: Need help about etherchannel and vlan configuration


But that's not solve my problem to obtain a best throughput.

Perhaps I don't ask the good qestions. Also, this is my real problem :

My network had a 2821 cisco with a collected SDSL interface (each SDSL is associated to one vlan).

My ISP deliver each link ATM to a specific VLAN on the same trunk interface. I had at this time more than 20 VLANS.

My ISP can supply only 2 wires on SDSL link that provides a throughput of 4MBit/s max

For one client I want to build a bonding between 2 SDSL card to deliver a 8M link. I'll buy a 1841 with 2 WIC-SHDSL-V2 to do that.

For 2 vlans (for example fast 0/3/0.501 and 0/3/0.502) I want to build an agregated link to obtain a throughput of 8MBit/s ATM for my client.

Do you know how I need to process on my cisco 2821 to agregated this 2 vlans ?

Do I need to use bridge interface ?

Also, an other question is it the same process in the CPE 1841 ?

Thanks for your help.

The schema is this :

                                              |                 |
modem 1801 WIC-1 ----------------| dslam/LAC|------------------ LNS/2801
                    WIC-2 ---------------|                 |                   2vlans 501 and 502