isis:interface vlan

[JosiahMg]

When I use the ip link add command on two Ubuntu systems to create an eth1.100 VLAN sub-interface and enable the ISIS protocol on the interface, I find that the sub-interface can not only establish an ISIS neighbor with the eth1.100 port of another Ubuntu, but also establish an ISIS neighbor with the eth1 port.

ip link add link eth1 name eth1.100 type vlan 100

R1 configuration:

interface eth1
  ip route isis 1
interface eth1.100
  ip route isis 1
router isis 1
  is-type level-2-only
  net 49.0000.0000.0001.00

R2 configuration:

interface eth1.100
  ip route isis 1
router isis 1
  is-type level-2-only
  net 49.0000.0000.0001.00

R1 show isis neighbor

SystemID     Interface      L     State
R2                  eth1           2       UP
R2                  eth1.100    2       UP

R2 show isis neighbor

SystemID     Interface      L     State
R1                  eth1.100    2       UP

[JosiahMg]

I'll resubmit