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  1. Hi Rene,

    thanks a lot for your helpful explanation, I simulated your lab and found something that I need your explanation for it.

    when I leaked 8.8.8.8 at R4, R2 calculated the metric of 8.8.8.8 with 168 as below:

    R2#sh ip route isis 1
          8.0.0.0/32 is subnetted, 1 subnets
    i ia     8.8.8.8 [115/168] via 192.168.24.4, 00:14:47, Ethernet0/2
    

    although R4 calculated it with 30 :

    R4#sh ip route isis
          8.0.0.0/32 is subnetted, 1 subnets
    i L2     8.8.8.8 [115/30] via 192.168.47.7, 00:50:55, Ethernet0/1
    

    the metric calculated with 40 at R2 when I configured the metric-style wide on all routers, I need your explanation for this please.

    Thanks,
    Walid

  2. Hi Walid,

    That’s a good question. I just booted this topology again and I see a metric of 40 on R2:

    R2#show ip route isis                         
    
    Gateway of last resort is 192.168.24.4 to network 0.0.0.0
    
    i*L1  0.0.0.0/0 [115/10] via 192.168.24.4, 00:14:23, GigabitEthernet0/2
          8.0.0.0/32 is subnetted, 1 subnets
    i ia     8.8.8.8 [115/40] via 192.168.24.4, 00:14:23, GigabitEthernet0/2
    i L1  192.168.13.0/24 [115/20] via 192.168.12.1, 00:15:16, GigabitEthernet0/1
    i L1  192.168.35.0/24 [115/30] via 192.168.12.1, 00:15:10, GigabitEthernet0/1
    i L1  192.168.47.0/24 [115/20] via 192.168.24.4, 00:15:16, GigabitEthernet0/2
    

    That’s without wide metrics:

    R2:

    router isis
     net 49.1234.0000.0000.0002.00
     is-type level-1
     log-adjacency-changes
    

    R4:

    router isis
     net 49.1234.0000.0000.0004.00
     log-adjacency-changes
     redistribute isis ip level-2 into level-1 route-map ROUTE_LEAKING
    

    What do you see in the database?

    R2#show isis database level-1 R4.00-00 detail 
    
    
    IS-IS Level-1 LSP R4.00-00
    LSPID                 LSP Seq Num  LSP Checksum  LSP Holdtime/Rcvd      ATT/P/OL
    R4.00-00              0x00000005   0xC9D0                 976/1199      1/0/0
      Area Address: 49.1234
      NLPID:        0xCC 
      Hostname: R4
      Metric: 10         IS R4.01
      IP Address:   192.168.47.4
      Metric: 10         IP 192.168.24.0 255.255.255.0
      Metric: 10         IP 192.168.47.0 255.255.255.0
      Metric: 30         IP-Interarea 8.8.8.8 255.255.255.255
    

    Rene

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