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VLAN routing newbie question...

Figured I would post this because I know how much you all must love these "newbie" questions... and a long one at that.

In any case, I am trying to setup a small, simple lab at home.

I have a Catalyst 2916M-XL switch and a 2624 router installed.

The switch is split down the middle, ports 1-8 VLAN1 and 9-15 VLAN 2. Port 16 is multi access and belongs to VLAN 1 and 2 and is where my router is attached.

All I am trying to do is route between the 2 VLANs but cannot seem to configure the router at this time. The E 0 interface is only a 10MB port and I was wondering if that is the problem? I have 2 sub interfaces, e 0.1 and e 0.2 created with "no ip address" on the e 0 interface. There does not seem to be the option for encapsulation or VLANs anywhere in the IOS (v 12.1.17) on the router. The switch appears to have configured ok. Some of the commands there on f 0/16 I did were switchport multi, switchport mode, and also did the ecapsulation isl1 and encapsulation isl 2 on the sub interfaces.

I have read and followed quite a bit of the documentation on CCO but, again, some of the commands it references do not seem to be availale to me on my router.

Can anyone please let me know if I am trying something that can't be done? Do I need to have a Fastethernet port to do ISL between to VLANs?

Thank you all for your time and assistance.


Re: VLAN routing newbie question...

You need fastethernet for ISL (first supported in 11.1) but I have read before that dot1q works on both 100Mbs and 10Mbs. Dot1q support came out in 12.0(1)T (12.1(3) T with the native option) but I think your ethernet interface doesn't support it. I believe its a hardware issue in your case.

Hope it helps.


Community Member

Re: VLAN routing newbie question...

I figured that was going to be the real issue. I'll try the dot1q option, but like you mentioned, the interface looks to be the real problem here.

Anyone need a 2524... real cheap? :)



Community Member

Re: VLAN routing newbie question...

The 2524 does not support trunking to enable your vlan routing.

Community Member

Re: VLAN routing newbie question...

Well my problem is that there are no commands which relate to VLANs or encapsulation on the router at all. So my guess is that this particular interface will not support either method. Closest option I have is for Bridge Group.

Thanks again,


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