IOS-XR:
router isis 1
is-type level-2-only
net 49.0001.0000.0000.0020.00
interface Loopback0
passive
address-family ipv4 unicast
!
!
interface GigabitEthernet0/0/0/0.1920
address-family ipv4 unicast
IOS-XE:
interface GigabitEthernet1.519
ip router isis
!
router isis
net 49.0001.0000.0000.0005.00
is-type level-2-only
passive-interface Loopback0