Justin Shore wrote:
I'm having trouble getting EoMPLS to work from a ME3750 to a 7201. I have some signaling but the VC just won't come up. The basic layout is a switchport on the ME3750; the xconnect is in the SVI associated with that switchport on the ME3750. The ME3750's P-facing interfaces are MPLS enabled. The 7600 core is MPLS enabled. The 7201 dual-homes to both core 7600s. The 7201's interfaces are MPLS enabled. I'm trying to terminate the xconnect on a sub-int of an onboard interface that's facing a 4948. I have a laptop on the ME3750 and I'm mapping an access int on the 4948 in the correct VLAN back across another network to my office (so I don't have to sit in a noisy head-end).
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Something just jumped out at me. The MTUs are different. Would that cause an issue? Gi0/2 on the 7201 is set to 9000 because hung off of the 4948 is a set of backhaul radios that I will be doing MPLS across. The customer-facing interface on the ME3750 is set to the default 1500. Do the MTUs have to match up? I'm going to have to do some research.
The MTU thing got me thinking (dangerous I know). I set the MTU on Gi0/2 on 7201 back to 1500 and the VC immediately came up and passed traffic. The MTU on the sub-int of the 7201 can't be set separately from the physical interface's MTU:
% Non-TRISL encapsulated sub-interface GigabitEthernet0/2.130 does not support user settable mtu.
MPLS MTU on the sub-int or physical interface doesn't appear to affect EoMPLS VCs either. Is there a way to change the MTU on the sub-int to allow the VC to come up?
Along this same train of thought, what's best practice for EoMPLS links when mixed with sub-ints? Should I strive to keep infrastructure links separate from customer links? Ie don't put them together on the same interface even if separate by sub-ints? In this example Gi0/0 and 1 on the 7201 are what dual-home the 7201 to the 7600 core. Gi0/2 connects to the 4948. Gi0/3 is currently unused. I could also connect Gi0/3 to the 4948. In that case I could then dedicate that interface to the infrastructure link (only the radio at this point) on the 4948. Since I'm standardizing on a MTU of 9000 for infrastructure links I could keep them all on the same physical interface of the 7201. For that matter in the short-term I could also just connect the radio directly to the 7201.
So what's best practice for EoMPLS on sub-ints? Had I not run into this problem this afternoon I'd have run into it next week during another new deployment. In that case I'll be on a 7206 with only 3 GigE ints but I could make it work. Thoughts?
Thanks Justin _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
