LLS allows for the extension of existing OSPF packets to provide additional bit space. The additional bit space enables greater information per packet exchange between OSPF neighbors.
Symptom:
When enabling LLS on the router, OSPF adjacency with the ASA stuck in INIT state.
Router(config)#int g0/0/1
Router(config-if)#ip OSPF lls (command to enable LLS)
On the Peer device, we get below Error (neighbor detached)
%OSPF-5-ADJCHG: Process 100, Nbr x.x.x.x on GigabitEthernet0/0/1 from FULL to DOWN, Neighbor Down: Interface down or detached.
Router(config)#logg
OSPF-100 ADJ Gi0/0/1: Cannot see ourself in hello from x.x.x.x, state INIT
Router# sh ip ospf neighbor
Neighbor ID Pri State Dead Time Address Interface
x.x.x.x 1 INIT/DROTHER 00:00:16 y.y.y.y GigabitEthernet0/0/1 <----- Stuck in INIT
On ASA, the following log is generated:
ASA5525(config)# %ASA-4-409003: Received invalid packet: Bad LLS TLV length from Y.Y.Y.Y
Soultion:
A temporary solution is to disable the LLS on the router or switch connected to ASA.
Interface gigabitEthernet 0/0/1
Ip ospf lls disable (Disable LLS)