[c-nsp] dot1q question

[Michael K. Smith]

On 4/9/06 7:01 AM, "Frank Kempermann" <cisco-nsp at kempermann.de> wrote:

> I currently have a Cisco 7204 connected with a Catalyst 2924 per trunk. On
> another port of the 2924 a 100FETH WAN route is connected. This secondary
> location is connected through a trunk and a VLAN (ISL).
> 
> I now wanted to exchange the Catalyst 2924 with a 2950, which supports dot1q
> only. Besides that the FETH trunk should be exchanged with a GETH trunk in
> the 7204.
> 
> I tried out many possibilities; using the following ISL-setup with a
> 7204FETH and a 2924 everything runs fine, but using dot1q it doesn't work,
> where could be my error? I cannot reach the respective IP's from the 7204 to
> the 3550, which is working when using ISL.
> 
> Do I have to do something with the VTP of the two switches? When using ISL
> this doesn't matter. Is something missing in the configuration?
> 
> I planned the following:
> 
> C7204 i/o GE ---trunk---2950GETH----WAN-FETH(Trunk)----C3550-LAN-FETH
> 
> C7204
> 
> I
> 
> I
> 
> interface Gigabitethernet 0/0.50
> 
> encapsulation dot1q 50
> 
> ip address x.x.x.x 255.255.255.248
> 
> I
> 
> I
> 
> C2950
> 
> I
> 
> I
> 
> interface GigabitEthernet0/1
> 
> switchport mode trunk
> 
> vlan database
> 
> vlan 50 name blabla
> 
> apply
> 
> interface FastEthernet0/23
> 
> switchport mode trunk
> 
> no ip address
> 
> duplex full
> 
> speed 100
> 
> I
> 
> I
> 
> C3550
> 
> I
> 
> interface FastEthernet0/13
> 
> description Uplink blabla
> 
> switchport trunk encapsulation dot1q
> 
> switchport trunk allowed vlan 1,50,1002-1005
> 
> switchport mode trunk
> 
> speed 100
> 
> duplex full
> 
> interface Vlan50
> 
> ip address x.x.x.x 255.255.255.248
> 

Hello:

What do you see when you do a "sho arp" on the router and a "sho
mac-address-table vlan 50" on both the 2950 and the 3550?  Are you seeing
the MAC address of the 3550's VLAN interface on the 7204 and the 7204's
interface address on the 3550?  How about in between?

Also, are all interfaces, including the VLAN 50 interface, showing UP/UP?

Mike