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. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

Basic Vlan routing, why doesn't this work?

I don't understand why this doesn't work. I have a 2912 switch and a 2621 Router. I'm just trying to setup basic vlan routing but I can't get the encapsulation working on the router, rather I can't even find the command.

I setup a dot1q trunk port on the switch and connected fa 0/0 of the router to it.

So now I'm trying to setup dot1q encap on the 2621 router but I can't find the command in any of the menu systems.

Searched the cisco site, found this article.

I was doing that, wondering why its not working. I get all the way to the part where you do the encap but that command doesn't exist.

I powered up a 2620 that I have an it does the exact same thing. What am I missing here?

S1(config)#int fa 0/0/ .1

LS1(config-subif)#ip address 5.1

Configuring IP routing on a LAN subinterface is only allowed if that

subinterface is already configured as part of an IEEE 802.10, IEEE 802.1Q, or ISL vLAN.

LS1(config-subif)#ecn nca ?

% Unrecognized command

LS1(config-subif)#enca enc ?

Interface configuration commands:

arp Set arp type (arpa, probe, snap) or timeout

backup Modify backup parameters

bandwidth Set bandwidth informational parameter

bridge-group Transparent bridging interface parameters

carrier-delay Specify delay for interface transitions

cdp CDP interface subcommands

default Set a command to its defaults

delay Specify interface throughput delay

description Interface specific description

exit Exit from interface configuration mode

ip Interface Internet Protocol config commands

llc2 LLC2 Interface Subcommands

mtu Set the interface Maximum Transmission Unit (MTU)

netbios Use a defined NETBIOS access list or enable name-caching

no Negate a command or set its defaults

New Member

Re: Basic Vlan routing, why doesn't this work?

Hmm that didn't copy and paste correctly. Basically there is no encapuslation command in any of the menus. I'm running IOS 12.3 and the other router I tried was 12.2.

I kept trying enca ? and it kept coming back with unrecog command.

Re: Basic Vlan routing, why doesn't this work?

You need an IP Plus feature set for trunking encap, do you have this feature set on your IOS?

New Member

Re: Basic Vlan routing, why doesn't this work?

Hmm, no idea. I'll go download an IOS Version that does have that and try it. Why would that not be a standard "feature" what good is a router if you can't encap a port and actually route vlan traffic?

Thanks for the reply. :)

New Member

Re: Basic Vlan routing, why doesn't this work?

That was it, I had no idea that wasn't part of a standard IOS.