３班の構成
L-----G
|     |
|     |
C-----T
|
U

●全てのRouterでIS-IS Level1を動かす。
・metric値の変更
  metricを同じにするとT→L間は、T->C->LとT->G->L
  でシェアされていた。(tracerouteで確認:LOG無し)
  L-G間のmetricを5低く設定したら、T->L間はT->G->L
  の経路が優先された。

・T-G間の切断
  T->G->Lの経路が優先されている際にT-G間のcableを抜くと
  T->C->Lへ迂回された。(tracerouteで確認:LOG無し)
  
●以下のLINKをdown/upさせた時のRouter-Cでの検出時間。
  - V-H間をDOWNさせる(cableを抜く)。
   9秒

  - V-H間をUPさせる(cableを差す)。
   12秒後

  - V-H間をDOWNさせる(Router-Hのe1をshutdown)。
   7秒後

  - V-H間をUPさせる(Router-Hのe1をno shutdown)。
   8秒後

  - M-K間をDOWNさせる(Router-Mでshutdown)。
   6.5秒

  - M-K間をUPさせる(Router-Mでno shutdown)。
   8.5秒

  - L-M間をDOWNさせる(Router-?でshutdown)。
   6秒

  - L-M間をUPさせる(Router-?でno shutdown)。
   12秒
------------------------------------------------------------
●Router Cのconfig
Router-C#writ t
Building configuration...

Current configuration:
!
version 11.1
service udp-small-servers
service tcp-small-servers
!
hostname Router-C
!
enable password janog
!
ip subnet-zero
no ip domain-lookup
clns routing
!
interface Loopback0
 ip address 10.3.0.2 255.255.255.255
 ip router isis JANOG
!
interface Ethernet0
 ip address 10.3.3.1 255.255.255.0
 ip router isis JANOG
 isis circuit-type level-1
!
interface Ethernet1
 no ip address
 shutdown
!
interface Serial0
 ip address 10.3.7.1 255.255.255.0
 ip router isis JANOG
 no fair-queue
!
interface Serial1
 ip address 10.3.2.2 255.255.255.0
 ip router isis JANOG
 isis circuit-type level-1
!
router isis JANOG
 redistribute static ip metric 0 metric-type internal
 level-1
 net 47.0000.0100.0300.0002.00
 is-type level-1
!
ip classless
ip route 192.168.30.0 255.255.255.0 Serial0
ip route 192.168.31.0 255.255.255.0 Serial0
logging buffered
!
banner login ^C
Grp.3 Router-C 10.3.0.2
^C
!
line con 0
line aux 0
line vty 0 4
 password janog
 login
!
end
------------------------------------------------------------
●Router Gのconfig
sh ru
Building configuration...

Current configuration:
!
version 11.2
service timestamps debug uptime
no service password-encryption
no service udp-small-servers
no service tcp-small-servers
!
hostname router-G
!
enable password janog
!
ip subnet-zero
no ip domain-lookup
clns routing
clock timezone JST -9
!
interface Loopback0
 ip address 10.3.0.4 255.255.255.255
 ip router isis JANOG
 isis circuit-type level-1
!
interface Ethernet0
 ip address 10.3.5.1 255.255.255.0
 ip router isis JANOG
 isis circuit-type level-2-only
!
interface Ethernet1
 no ip address
 shutdown
!
interface Serial0
 description isis level-1 connection
 ip address 10.3.4.1 255.255.255.0
 ip router isis JANOG
 clockrate 2000000
 isis circuit-type level-1
!
interface Serial1
 ip address 10.3.1.2 255.255.255.0
 ip router isis JANOG
 clockrate 2000000
 isis circuit-type level-1
 isis metric 5 level-1
!
router isis JANOG
 redistribute connected metric 0 metric-type internal level-2
 net 47.0003.0100.0300.0004.00
!
ip classless
logging trap debugging
logging source-interface Loopback0
logging 10.2.1.20
!
banner login ^C 3-Group Router-G^C
!
line con 0
line aux 0
line vty 0
 password janog
 login
 transport preferred none
line vty 1 4
 password janog
 login
!
ntp server 10.2.0.1
end
router-G#