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Problems with VLANs between cisco 7200 routers

Hi, I have a point to point link between 2 Cisco 7200s that I'm being required to add VLAN tagging to. Here are the interface configs:

Router A:

interface FastEthernet5/0 no ip address duplex full ! interface FastEthernet5/0.253 encapsulation dot1Q 253 ip address xxx.xxx.xxx.249 255.255.255.252

Router B:

interface FastEthernet4/0 no ip address duplex full ! interface FastEthernet4/0.253 encapsulation dot1Q 253 ip address xxx.xxx.xxx.250 255.255.255.252

However, when AT&T forces tagging on the ports, I cannot ping from .

249 to .250, and AT&T cannot see my MAC address on their switches inbetween and zero traffic on the VLAN.

Does anyone have any ideas?

Router A is a 7206VXR running 12.2(4r) Router B is a 7204VXR running 12.2(12a)

Thank you.

Reply to
jlamanna
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The config looks fine, thats just the way to do it on the 7200.

BUT, are you sure you need to provide VLAN tagging back to AT&T? Thats kind of a weird setup for a service-provider, usually they would be the ones tagging or untagging their VLAN setup.

I wouldn't trust them unless you specificly asked for a setup like this, and then I wouldn't trust them to get it right.. :-/

Reply to
Doug McIntyre

some Ethernet over SDH gear will pass any tag, others need the tag numbers specified in the transmission kit.

check is the non tagged stuff still get thru - if yes, but tagged doesnt then either

  1. you and AT+T are not making the change at the same time
  2. there is something wrong at their side
  3. or they dont mean tags at all - VRFs?.
Reply to
Stephen

The reason is that I have two circuits coming into one physical port (this is a fiber circuit with ethernet handoff on both ends), so they need the 802.1q info to decide which outbound circuit to route it to.

Reply to
jlamanna

sounds like the VLAN numbers may be wrong.

Note that if there is MPLS in the way then the VLAN numbers do not have to be the same at each end.

FWIW i would not be happy if someone selling me a service couldnt explain how i need to set up or how to use it.

If you have an SLA / fault reporting setup, maybe you should log ii as a fault with the AT&T NMC? - the engineers will have the info on setup, or can check on the carrier equipment to see.

Or try asking or looking on any online portal to see what the detail definition is set to.

Or use a sniffer to look at the packets and read

Have they left CDP or similar turned on?

Reply to
Stephen

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