Configuring ISL on FastEthernet subinterface.

[Joley]

Hi all,
When I tried to change the encapsulation to ISL on FastEthernet subinterface for the purpose of Inter-VLAN trunking, the router does not recognize the command (it's a 2620 router). Moreover, the encapsulation command is not even in the command list. Does anyone encounter the same problem? Responses are very appreciated.
Thanks.

 

[svermill]

I don't think you set the encapsulation on the subinterface do you? I'm on the road and away from my lab so I can't verify this for you but I'm pretty sure you set encap on the main interface.

 

[Joley]

Yes svermill, I was able to create 3 subinterfaces on the 10/100Mbps FastEthernet port. But when I attempted to set encapsulation to ISL, the router did not recognize the command. I tried to do it in the interface mode but it didn't work either, the command was not in the list in either case. I began to think the problem was the IOS image. By the way, is IOS version 12.0 the newest?
Thanks.

 

[rburke]

No, the newest IOS verisons are the 12.2.x. You might want to check out

http://www.cisco.com

and see if you can find what IOS version you'll need for ISL trunking.

burke

 

[wybnormal]

Here is snippet of my 2620 with both ISL and 802.1Q

!
interface FastEthernet0/0
no ip address
no ip directed-broadcast
!
interface FastEthernet0/0.1
encapsulation isl 1
ip address 10.10.10.1 255.255.255.0
no ip redirects
no ip directed-broadcast
!
interface FastEthernet0/0.2
encapsulation dot1Q 100
ip address 11.11.11.1 255.255.255.0
no ip directed-broadcast
!

Here are the command line options
DDD-test(config-subif)#encapsulation ?
dot1Q IEEE 802.1Q Virtual LAN
isl Inter Switch Link - Virtual LAN encapsulation
sde IEEE 802.10 Virtual LAN - Secure Data Exchange
tr-isl Token Ring Inter Switch Link - Virtual LAN encapsulation


My IOS is earlier then yours

DDD-test uptime is 7 minutes
System restarted by power-on
System image file is "flash:c2600-js-mz.120-2.XC2"


What version are you using? not the rev level, what is the filename of the IOS?

In my IOS, the js means it's an enterprise load. VLAN encapsulation may not be part of all 2620 loads OR you have the wrong load on the router.. for example, a 2610 load on a 2620.. I did not think this could be done but it would explain why you do not have the encapsulation command... anyone know for sure if this could be done?

MikeS
Find me at

http://www.packetattack.com

"Take advantage of the enemy's unreadiness, make your way by unexpected routes, and attack unguarded spots."
Sun Tzu