troubleshooting Question

Would like to use 1Q VLAN to trunk two cisco routers

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inteliportFlag for United States of America asked on
NetworkingNetwork Operations
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Currently trying to connect two locations via 1Q VLAN in order to migrate to new internet gateway.  
The future goal is to aggregate all locations via Ethernet to one central location using vlans.

My issues is that I cannot ping either side when I try to use sub-interfaces, here's the traffic flow and setup.

Location-1                       Location-2
3660 -> ME3400 Port1 -> ME3400 Port 1-> 3Com4200 -> 7200

7200 -> ME3400 Port 2 -> Internet

The 3660 connects to the ME3400 switch on port1 via FastEthernet0/1 with an ip address of

The ME3400 Port1 on the other side connects to a 4200 3Com switch and then the 3Com switch connects to the 7200 on interface GigabitEthernet0/1
The interface GigabitEthernet0/1 interface has a secondary address of

Then on interface GigabitEthernet0/2 the 7200 connects back to the ME3400 Port-2 which is handed off to the new Internet Gateway

The Telco owns both ME3400's

The 3660 looks like this (no vlan) this works

interface FastEthernet0/1
 ip address
 speed auto
 no cdp enable

The 7200 looks like this (no vlan) this works

interface GigabitEthernet0/1
 ip address public-ip secondary
 ip address public-ip secondary
 ip address public-ip secondary
 ip address secondary
 ip address public-ip
 ip route-cache same-interface
 duplex auto
 speed auto
 media-type rj45
 no negotiation auto

The above works and I can ping both and from both routers I can ping the internet if I setup a route, but here's the issue,

When I setup up both sides for vlans

interface FastEthernet0/1.100
 ip address
 encapsulation dot1Q 100
 no cdp enable

interface GigabitEthernet0/1.100
ip address
 encapsulation dot1Q 100
 no cdp enable

I cannot ping ether one, my guess is the routers are stripping the tags off the vlans and not routing the ip's, or It can't find the proper route, I tired just about everything to get this to route using the vlans, except the one that works ;)

I need to get this to work so that we can issue Vlans from different locations that will be backed hauled with Ethernet to the 7200 Internet gateway, once this is working I will have the Telco point all the public Class C's to the new 7200 gateway.

Any ideas,

Thanks in advance

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