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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

  3. Just to be picky: at the beginning there is a “We can deal with this by” that repeats.

    Thank you for all these lessons, they are really great!
    Stefanita

  4. Hello Stuat

    Thanks for picking this up. You’re not being picky at all, we appreciate you bringing these things to our attention!

    Laz

  5. Hi Stefanita,

    I always appreciate it when people report errors :+1: Just fixed this.

    Rene

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