ASR920 and Nexus 7k port-channel

Hey all,

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We're recently moving from a ME3400e to an ASR920 for our edge. We normally have two layer 2 links running in a port-channel to our core from the ME3400. The core is two Nexus 7010's running VPC.

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Current configuration with ME3400e is below;

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interface Port-channel1 description [Global] LACP link to Core port-type nni switchport trunk allowed vlan <customer vlans> switchport mode trunk spanning-tree portfast trunk end ! interface GigabitEthernet0/1 description [Global] Uplink to Core01 port-type nni switchport trunk allowed vlan <customer vlans> switchport mode trunk udld port channel-group 1 mode active service-policy input PMAP-QoS-IN end ! interface GigabitEthernet0/2 description [Global] Uplink to Core02 port-type nni switchport trunk allowed vlan <customer vlans> switchport mode trunk udld port channel-group 1 mode active service-policy input PMAP-QoS-IN 

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As we can see with the following output, layer 2 port channel is up on me3400;

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Flags: D - down P - bundled in port-channel I - stand-alone s - suspended H - Hot-standby (LACP only) R - Layer3 S - Layer2 U - in use f - failed to allocate aggregator M - not in use, minimum links not met u - unsuitable for bundling w - waiting to be aggregated d - default port Number of channel-groups in use: 1 Number of aggregators: 1 Group Port-channel Protocol Ports ------+-------------+-----------+----------------------------------------------- 1 Po1(SU) LACP Gi0/1(P) Gi0/2(P) 

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Current configuration with Nexus core is below;

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interface port-channel60 description vPC link to Edge switchport switchport mode trunk switchport trunk allowed vlan <customer vlans> spanning-tree port type normal spanning-tree guard root no lacp graceful-convergence vpc 60 ! interface Ethernet2/6 description vPC 60 link to Edge switchport switchport mode trunk switchport trunk allowed vlan <customer vlans> udld enable channel-group 60 mode active no shutdown 

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As we can see with the following output layer 2 port channel is up on Core01 (core02 is the exact same config);

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Flags: D - Down P - Up in port-channel (members) I - Individual H - Hot-standby (LACP only) s - Suspended r - Module-removed S - Switched R - Routed U - Up (port-channel) M - Not in use. Min-links not met -------------------------------------------------------------------------------- Group Port- Type Protocol Member Ports Channel -------------------------------------------------------------------------------- 60 Po60(SU) Eth LACP Eth2/6(P) 

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Now we move to the new ASR920 and Nexus Core configuration, first the ASR920;

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interface Port-channel1 description [Global] LACP link to Core no ip address spanning-tree portfast trunk service instance trunk 1 ethernet encapsulation dot1q <customer vlans> rewrite ingress tag pop 1 symmetric service-policy input PMAP-QoS-IN bridge-domain from-encapsulation ! interface TenGigabitEthernet0/0/24 description [Global] Uplink to Core01 no ip address udld port ethernet dot1ad nni channel-group 1 mode active end ! interface TenGigabitEthernet0/0/25 description [Global] Uplink to Core02 no ip address udld port ethernet dot1ad nni channel-group 1 mode active end 

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From below output we can see that the port-channel is up as Layer 3, not layer 2 on the ASR920;

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Flags: D - down P/bndl - bundled in port-channel I - stand-alone s/susp - suspended H - Hot-standby (LACP only) R - Layer3 S - Layer2 U - in use f - failed to allocate aggregator M - not in use, minimum links not met u - unsuitable for bundling w - waiting to be aggregated d - default port Number of channel-groups in use: 1 Number of aggregators: 1 Group Port-channel Protocol Ports ------+-------------+-----------+----------------------------------------------- 1 Po1(RU) LACP Te0/0/24(bndl) Te0/0/25(D) RU - L3 port-channel UP State SU - L2 port-channel UP state P/bndl - Bundled S/susp - Suspended 

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The nexus core config is the exact same using the ASR920, just a different interface so I won't post that again, but the port-channel for the ASR920 on the nexus side is up at Layer 2. So the issue I am having here is the link appears to be going down, because one side is layer 3 and the other layer 2. Wondering if anyone has any insights into what's going on here?