IS-IS协议配置的实战讲解（可跟做）

2024-03-22 09:19:58

IS-IS应用场景配置

如图所示，客户网络所有路由器路由协议要求启用IS-IS，使全网路由可达。全部IS-IS进程号统一为100，其中RTA在Area49.0001区域为DIS，RTD与RTE之间要求采用P2P网络类型，RTE引入直连链路192.168.X.X，要求RTA访问Area49.0002走最优路径。根据上述描述，进行正确配置，使网络路由达到客户需求

NET地址编号

 RT1：49.0001.0000.0000.0001.00
 RT2：49.0001.0000.0000.0002.00
 RT3：49.0001.0000.0000.0003.00
 RT4：49.0002.0000.0000.0004.00
 RT5：49.0002.0000.0000.0005.00
IS-IS协议配置的实战讲解（可跟做）

问题一

需不需要配置IP地址？
回答：需要有IP地址，原因是路由寻址，在IP环境中，是为了支持IP环境，IP环境中的NET
地址是为了标记路由器以及area 而在CLNP环境中，可以不用IP地址

第一步：IP地址的配置和NAT地址配置

AR1的配置

#
interface GigabitEthernet0/0/0
 ip address 192.168.123.1 255.255.255.0 
 isis enable 100
#
isis 100
 is-level level-1
 network-entity 49.0001.0000.0000.0001.00
#

AR2的配置

#
interface GigabitEthernet0/0/0
 ip address 192.168.123.2 255.255.255.0 
 isis enable 100
#
interface GigabitEthernet0/0/1
 ip address 192.168.24.2 255.255.255.0 
 isis enable 100
#
isis 100
network-entity 49.0001.0000.0000.0002.00
#

AR3的配置

#
interface GigabitEthernet0/0/0
 ip address 192.168.123.3 255.255.255.0 
 isis enable 100
#
interface GigabitEthernet0/0/1
 ip address 192.168.34.3 255.255.255.0 
 isis enable 100
#
isis 100
network-entity 49.0001.0000.0000.0003.00
#

AR4的配置

#
interface GigabitEthernet0/0/0
 ip address 192.168.34.4 255.255.255.0 
 isis enable 100
#
interface GigabitEthernet0/0/1
 ip address 192.168.24.4 255.255.255.0 
 isis enable 100
#
interface GigabitEthernet0/0/2
 ip address 192.168.45.4 255.255.255.0 
 isis enable 100
#
isis 100
 is-level level-2
 network-entity 49.0002.0000.0000.0004.00
#

AR5的配置

#
interface GigabitEthernet0/0/2
 ip address 192.168.45.5 255.255.255.0 
 isis enable 100
#
interface LoopBack1
 ip address 192.168.1.1 255.255.255.0 
#
interface LoopBack2
 ip address 192.168.2.1 255.255.255.0 
#
interface LoopBack3
 ip address 192.168.3.1 255.255.255.0 
#
isis 100
 is-level level-2
 network-entity 49.0002.0000.0000.0005.00
#

检查如下：

在R1、2、3、4、5上面进行检查

检查is-is的邻居关系是否UP

<R1>display isis peer 

                         Peer information for ISIS(100)

  System Id     Interface          Circuit Id       State HoldTime Type     PRI
-------------------------------------------------------------------------------
0000.0000.0002  GE0/0/0            0000.0000.0001.01 Up   22s      L1       64 
0000.0000.0003  GE0/0/0            0000.0000.0001.01 Up   23s      L1       64 

Total Peer(s): 2

查看在R1使能IS-IS的接口

<R1>display isis interface 

                      Interface information for ISIS(100)
                      -----------------------------------
 Interface       Id      IPV4.State          IPV6.State      MTU  Type  DIS   
 GE0/0/0         001         Up                 Down         1497 L1/L2 Yes/No 
<R1>

第二步：其中RTA在AREA49.0001区域为DIS，RTD与RTE之间要求采用P2P网络类型

在R1的接口下面进行配置

#
interface GigabitEthernet0/0/0
 ip address 192.168.123.1 255.255.255.0 
 isis enable 100
 isis dis-priority 120 level-1
#

检查R1是否为DIS

[R1]display isis interface GigabitEthernet 0/0/0 

                      Interface information for ISIS(100)
                      -----------------------------------
 Interface       Id      IPV4.State          IPV6.State      MTU  Type  DIS   
 GE0/0/0         001         Up                 Down         1497 L1/L2 Yes/No 
[R1]

RTD与RTE之间要求采用P2P网络类型

R4的配置

#
interface GigabitEthernet0/0/2
isis circuit-type p2p
#

R5的配置

#
interface GigabitEthernet0/0/2
isis circuit-type p2p
#

检查如下

[R4]display isis brief 

                    ISIS Protocol Information for ISIS(100)
                    ---------------------------------------
SystemId: 0000.0000.0004      System Level: L2    
Area-Authentication-mode: NULL
Domain-Authentication-mode: NULL
Ipv6 is not enabled
ISIS is in invalid restart status
ISIS is in protocol hot standby state: Real-Time Backup

Interface: 192.168.45.4(GE0/0/2)
Cost: L1 10        L2 10                Ipv6 Cost: L1 10   L2 10   
State: IPV4 Up                          IPV6 Down
Type: P2P                               MTU: 1497      
Priority: L1 64   L2  64   
Timers:     Csnp: L12 10  , Retransmit: L12 5   , Hello: 10  ,
Hello Multiplier: 3            , LSP-Throttle Timer: L12 50  

Interface: 192.168.24.4(GE0/0/1)
Cost: L1 10        L2 10                Ipv6 Cost: L1 10   L2 10   
State: IPV4 Up                          IPV6 Down
Type: BROADCAST                         MTU: 1497      
Priority: L1 64   L2 64   
Timers:     Csnp: L1 10    L2 10    ,Retransmit: L12 5   , Hello: L1 10 L2 10  ,

Hello Multiplier: L1 3    L2 3     , LSP-Throttle Timer: L12 50  

Interface: 192.168.34.4(GE0/0/0)
Cost: L1 10        L2 10                Ipv6 Cost: L1 10   L2 10   
State: IPV4 Up                          IPV6 Down
Type: BROADCAST                         MTU: 1497      
Priority: L1 64   L2 64   
Timers:     Csnp: L1 10    L2 10    ,Retransmit: L12 5   , Hello: L1 10 L2 10  ,

Hello Multiplier: L1 3    L2 3     , LSP-Throttle Timer: L12 50

第三步：RTE引入直连链路192.168.X.X

在R5上面进行引入直连路由

#
isis 100
 is-level level-2
 network-entity 49.0002.0000.0000.0005.00
 import-route direct 
#

因为非骨干区域没有到达骨干区域的路由，我们可以在R2和R3上面做重发布，把骨干区域的路由引入到非骨干区域当中

在R2上面进行配置

#
isis 100
 network-entity 49.0001.0000.0000.0002.00
 import-route isis level-2 into level-1
#

在R3上面进行配置

#
isis 100
 network-entity 49.0001.0000.0000.0002.00
 import-route isis level-2 into level-1
#

在R1上面检查到达骨干区域的路由情况

<R1>display ip routing-table protocol isis 
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : ISIS
         Destinations : 7        Routes : 12       

ISIS routing table status : <Active>
         Destinations : 7        Routes : 12

Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface

        0.0.0.0/0   ISIS-L1 15   10          D   192.168.123.3   GigabitEthernet
0/0/0
                    ISIS-L1 15   10          D   192.168.123.2   GigabitEthernet
0/0/0
    192.168.1.0/24  ISIS-L1 15   94          D   192.168.123.2   GigabitEthernet
0/0/0
                    ISIS-L1 15   94          D   192.168.123.3   GigabitEthernet
0/0/0
    192.168.2.0/24  ISIS-L1 15   94          D   192.168.123.2   GigabitEthernet
0/0/0
                    ISIS-L1 15   94          D   192.168.123.3   GigabitEthernet
0/0/0
    192.168.3.0/24  ISIS-L1 15   94          D   192.168.123.2   GigabitEthernet
0/0/0
                    ISIS-L1 15   94          D   192.168.123.3   GigabitEthernet
0/0/0
   192.168.24.0/24  ISIS-L1 15   20          D   192.168.123.2   GigabitEthernet
0/0/0
   192.168.34.0/24  ISIS-L1 15   20          D   192.168.123.3   GigabitEthernet
0/0/0
   192.168.45.0/24  ISIS-L1 15   30          D   192.168.123.2   GigabitEthernet
0/0/0
                    ISIS-L1 15   30          D   192.168.123.3   GigabitEthernet
0/0/0

ISIS routing table status : <Inactive>
         Destinations : 0        Routes : 0

第四步：要求RTA访问AREA49.0002走最优路径

在R3上面修改isis的开销值

#
interface GigabitEthernet0/0/1
 ip address 192.168.34.3 255.255.255.0 
 isis enable 100
 isis cost 60
#

在R4上面修改isis的开销值

#
interface GigabitEthernet0/0/0
 ip address 192.168.34.4 255.255.255.0 
 isis enable 100
 isis cost 60
#

在R1上面检查到达骨干区域的路由情况

<R1>display ip routing-table protocol isis 
Route Flags: R - relay, D - download to fib
------------------------------------------------------------------------------
Public routing table : ISIS
         Destinations : 7        Routes : 8        

ISIS routing table status : <Active>
         Destinations : 7        Routes : 8

Destination/Mask    Proto   Pre  Cost      Flags NextHop         Interface

        0.0.0.0/0   ISIS-L1 15   10          D   192.168.123.3   GigabitEthernet
0/0/0
                    ISIS-L1 15   10          D   192.168.123.2   GigabitEthernet
0/0/0
    192.168.1.0/24  ISIS-L1 15   94          D   192.168.123.2   GigabitEthernet
0/0/0
    192.168.2.0/24  ISIS-L1 15   94          D   192.168.123.2   GigabitEthernet
0/0/0
    192.168.3.0/24  ISIS-L1 15   94          D   192.168.123.2   GigabitEthernet
0/0/0
   192.168.24.0/24  ISIS-L1 15   20          D   192.168.123.2   GigabitEthernet
0/0/0
   192.168.34.0/24  ISIS-L1 15   70          D   192.168.123.3   GigabitEthernet
0/0/0
   192.168.45.0/24  ISIS-L1 15   30          D   192.168.123.2   GigabitEthernet
0/0/0

ISIS routing table status : <Inactive>
         Destinations : 0        Routes : 0
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