is-is基础实验

Posted 2021-02-20 miaocongcong

实验拓扑：

 

 

 

is-is配置：

router isis
net 49.0000.0000.0002.00
R2:
is-type level-1-2
int e0/0
ip router isis
int lo0
ip router isis

R3:
router isis
net 49.0000.0000.0003.00
is-type level-1-2
int e0/0
ip router isis
int lo0
ip router isis

R4:
router isis
net 49.0000.0000.0004.00
is-type level-1-2
int e0/0
ip router isis
int lo0
ip router isis

 

R2#show clns int e0/0  
Ethernet0/0 is up, line protocol is up
  Checksums enabled, MTU 1497, Encapsulation SAP
  ERPDUs enabled, min. interval 10 msec.
  CLNS fast switching disabled
  CLNS SSE switching disabled
  DEC compatibility mode OFF for this interface
  Next ESH/ISH in 35 seconds
  Routing Protocol: IS-IS
    Circuit Type: level-1-2
    Interface number 0x0, local circuit ID 0x1
    Level-1 Metric: 10, Priority: 64, Circuit ID: R4.01
    DR ID: R4.01
    Level-1 IPv6 Metric: 10
    Number of active level-1 adjacencies: 2
    Level-2 Metric: 10, Priority: 64, Circuit ID: R4.01
    DR ID: R4.01
    Level-2 IPv6 Metric: 10
    Number of active level-2 adjacencies: 2
    Next IS-IS LAN Level-1 Hello in 5 seconds
    Next IS-IS LAN Level-2 Hello in 2 seconds

 

通过上述输出可以看出DIS为R4，R2接口isis的优先级默认为64，我们可以将R3，R4接口优先级改小，让R2成为DIS。命令：

int e0/0

isis priority 0

R2#show clns int e0/0
Ethernet0/0 is up, line protocol is up
  Checksums enabled, MTU 1497, Encapsulation SAP
  ERPDUs enabled, min. interval 10 msec.
  CLNS fast switching disabled
  CLNS SSE switching disabled
  DEC compatibility mode OFF for this interface
  Next ESH/ISH in 33 seconds
  Routing Protocol: IS-IS
    Circuit Type: level-1-2
    Interface number 0x0, local circuit ID 0x1
    Level-1 Metric: 10, Priority: 64, Circuit ID: R2.01
    DR ID: R2.01
    Level-1 IPv6 Metric: 10
    Number of active level-1 adjacencies: 2
    Level-2 Metric: 10, Priority: 64, Circuit ID: R2.01
    DR ID: R2.01
    Level-2 IPv6 Metric: 10
    Number of active level-2 adjacencies: 2
    Next IS-IS LAN Level-1 Hello in 2 seconds
    Next IS-IS LAN Level-2 Hello in 1 seconds

邻居、路由信息输出：

R2#show clns neighbors 
System Id      Interface   SNPA                State  Holdtime  Type Protocol
R3             Et0/0       aabb.cc00.3000      Up     29        L1L2 IS-IS
R4             Et0/0       aabb.cc00.4000      Up     26        L1L2 IS-IS

R2#show isis neighbors 

System Id      Type Interface   IP Address      State Holdtime Circuit Id
R3             L1   Et0/0       192.168.10.3    UP    22       R2.01              
R3             L2   Et0/0       192.168.10.3    UP    24       R2.01              
R4             L1   Et0/0       192.168.10.4    UP    26       R2.01              
R4             L2   Et0/0       192.168.10.4    UP    29       R2.01  

R2#show ip route isis 
Codes: L - local, C - connected, S - static, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area 
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2
       i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2
       ia - IS-IS inter area, * - candidate default, U - per-user static route
       o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP
       a - application route
       + - replicated route, % - next hop override

Gateway of last resort is not set

      3.0.0.0/32 is subnetted, 1 subnets
i L1     3.3.3.3 [115/20] via 192.168.10.3, 00:40:54, Ethernet0/0
      4.0.0.0/32 is subnetted, 1 subnets
i L1     4.4.4.4 [115/20] via 192.168.10.4, 00:40:18, Ethernet0/0