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I have the below output from an IOS-XR box:

RP/0/RSP0/CPU0:RTR1#show route 10.10.10.10
Wed Mar 27 13:34:52.553 IST

Routing entry for 10.10.10.10/32
  Known via "isis IGP", distance 115, metric 261, type level-2
  Installed Mar 27 01:21:50.992 for 12:13:01
  Routing Descriptor Blocks
    172.16.185.6, from 10.10.10.10, via TenGigE0/0/0/1, Backup
      Route metric is 0
    172.16.184.253, from 10.10.10.10, via Bundle-Ether7, Protected
      Route metric is 261
  No advertising protos.

Q1:what is the meaning of 'Route metric is 0' in the above output?

Q2: Is fast-reroute in any way related to Q1 ? I see that fast-reroute is configured under BE7 and not under Te0/0/0/1 in the running config.

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  • Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer. – Ron Maupin♦ Feb 21 '18 at 17:16
  • the given answer does not help – fsociety Feb 24 '18 at 12:13
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    I think that actually means that it is a directly connected network, so it has received no metrics from other routers to increase the metric. If you look at the routing table, you will see that the network is directly connected. – Ron Maupin♦ Feb 24 '18 at 21:10
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Route metrics are used by routing protocols to determine the best paths through your network. The actual metric isn't used to determine the path unless the Administrative Distance is the same between two or more paths. Cisco uses a default Administrative Distance of 0 for directly connected paths. If you want to learn more about Administrative Distance, here's a link to Cisco's support doc on it. As far as actual routing metrics, that depends on which routing protocols you're using. Here's a short explanation of a few metrics.

As for the fast-reroute command, that's used on a Label Switched Path in order to continue passing traffic even in the event of a link or node failure. A good explanation of Label Switched Paths can be found here, and the Cisco support doc on Fast Reroute links can be found here.

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0

Metric 0 is the end of your route in the network

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  • can you please explain with the help of a simple topology, i don't actually understand what you intend to say? – fsociety Feb 24 '18 at 4:11

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