IP Link-State Routing Protocols - CCIE Routing and Switching Exam Certification Guide - page 404

Example 8-20 IS-IS Configuration for Router 9 (Continued)
!
router isis cisco
redistribute static ip metric 60 metric-type external level-1-2
default-information originate
net 49.0000.0001.0002.00
!
ip classless
ip route 10.0.0.0 255.0.0.0 Null0
Ethernet 0 has the same L2 password as the Router 8 Ethernet. These passwords must be the
same for an adjacency to be formed. No priority is set on Ethernet 0, so the default value, 64, is
used. Router 9 is an L1/L2 IS. It forms an L2 adjacency with Router 8. Because Serial 0 has no
circuit-type defined, L1 and L2 adjacencies can be formed. If Router 10 is an L1-only IS, or if
the serial interface on Router 10 is configured with the isis circuit-type level-1-only command,
only L1 adjacencies are formed. Otherwise, both L1 and L2 adjacencies are formed. The isis
metric command changes the default metric from 10 to 40 for L1 routes on Serial 0. The static
IP address is redistributed into IS-IS as an L1 and an L2 external route with a metric of 60. A
default route is originated by this IS and advertised to IS-IS L2 ISs.
The configuration for Router 10 is shown in Example 8-21.
Example 8-21 IS-IS Configuration for Router 10
hostname Router10
!
interface Loopback0
ip address 192.16.100.3 255.255.255.255
ip router isis cisco
!
interface Ethernet0
ip address 192.16.100.33 255.255.255.240
ip router isis cisco
isis circuit-type level-1
!
interface Serial0
ip address 192.16.100.242 255.255.255.252
ip router isis cisco
no fair-queue
isis metric 40 level-1
!
router isis cisco
net 49.0000.0001.0001.00
!
ip classless
Router 10 is not defined as an L1-only IS, nor is Serial 0. L1 and L2 adjacencies are, therefore,
established with Router 9.