MPLS LDP issue on ME3750

[meritcisco]

Working on a SP Lab which includes a ME3750 as a PE. There is full connectivity between all devices from the PE until I enable mpls on the interfaces pointing to the upstream P routers.

PE-Cisco_ME3750(config)#int fa1/0/22
PE-Cisco_ME3750(config-if)#no mpls ip

PE-Cisco_ME3750(config-if)#int fa1/0/24
PE-Cisco_ME3750(config-if)#no mpls ip

PE-Cisco_ME3750#ping 3.47.28.11

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.47.28.11, timeout is 2 seconds:
!!!!!

When mpls is enabled on the interfaces, I see the following

%LSD-2-APP_NOTSUPP: FastEthernet1/0/24 interface does not support app LDP
-Traceback= 423DB4z 16A089Cz 179C290z 179D070z 16B2684z 185BBD8z 1859F80z 183BD6Cz 18062B0z 18068DCz 1806C74z 1806D4Cz 3764FCz 378F74z 39B5D4z 39BB70z

PE-Cisco_ME3750#show mpls forwarding-table 3.47.28.11
Local Outgoing Prefix Bytes Label Outgoing Next Hop
Label Label or Tunnel Id Switched interface
23 21 3.47.28.11/32 0 drop
21 3.47.28.11/32 0 drop

PE-Cisco_ME3750#ping 3.47.28.11

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 3.47.28.11, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)

[Harold Ritter · Accepted solution]

This is normal behavior. The 3750ME only supports MPLS on the Gigabit Ethernet interfaces. The 3750ME states the following:

"Enter interface configuration mode, and specify the Layer 3 ES interface connected to the MPLS network. Valid ES interfaces include gigabitethernet1/1/1, gigabitethernet1/1/2, and VLANs."

https://www.cisco.com/c/en/us/td/docs/switches/metro/catalyst3750m/software/release/12-2_55_se/configuration/guide/3750metro_scg/swmpls.html

Regards,