[c-nsp] EoMPLS from ME3750 to 7201 GigE sub-int

[Justin Shore]

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).

Here's the ME3750's relevant config:

no mpls traffic-eng auto-bw timers frequency 0
mpls label protocol ldp
mpls ldp graceful-restart
mpls ldp router-id Loopback0 force
!
vlan 130
  name vlan0130.cox-ptp-EOMPLS
!
interface FastEthernet1/0/3
  description TO Cox F.7 - 10Mbps Kan-Ed
  switchport access vlan 130
  switchport mode dot1q-tunnel
  no keepalive
  no cdp enable
  spanning-tree portfast
  spanning-tree bpdufilter enable
!
interface GigabitEthernet1/1/1
  description TO 7613-1.clr Gi1/11
  no switchport
  ip address
  ip router isis
  mpls label protocol ldp
  mpls ip
  clns mtu 1496
  isis circuit-type level-2-only
  isis network point-to-point
  isis metric 100
  isis authentication mode md5
  isis authentication key-chain ISIS-AUTH
  isis bfd
!
interface Vlan130
  description EoMPLS VC 130 to 7201-1.clr Gi0/2.130
  no ip address
  xconnect aaa.bbb.ccc.ddd 130 encapsulation mpls


And here's the 7201's relevant config:

mpls label protocol ldp
mpls ldp graceful-restart
mpls ldp router-id Loopback0 force
!
interface GigabitEthernet0/2
  description TO 4948-1.clr Gi1/45
  mtu 9000
  no ip address
  duplex auto
  speed auto
  negotiation auto
!
interface GigabitEthernet0/2.130
  description EoMPLS TO me3750-1.dc Vl130 (Fa1/0/3) - 10Mbps PtP
  encapsulation dot1Q 130
  xconnect 10.64.0.37 130 encapsulation mpls


I'll skip the 4948 config but I'll say that vl130 is permitted on 
Gi1/45, it has been created and it was assigned to my test access 
interface.  None of the other VLANs served from sub-ints are having trouble.

When I bring up the xconnect on the me3750 here's what it logs:

000181: Jan 17 18:38:31.914 CST: AToM LDP [10.64.0.43]: Sending label 
mapping msg
000182: Jan 17 18:38:31.914 CST: AToM LDP [10.64.0.43]: Sending label 
mapping msg vc type 4, cbit 0, vc id 130, group id 0, vc label 231, 
status 0x00000000/0x00000000, mtu 1500, peer vlan id 0   , vc handle 
0x18000001

Here's what I get on the 7201 when I unshut the sub-int:

003629: Jan 17 18:39:26.401 CST: AToM LDP [10.64.0.37]: Sending label 
mapping msg
vc type 4, cbit 0, vc id 130, group id 0, vc label 223, status 0, mtu 
9000, peer vlan id 0


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.

Thanks
  Justin