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Cisco Show ip route question

Posted on 2014-10-10
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Last Modified: 2014-10-19
I have some fail over routing in place on my Cisco 2921 voice router and i am trying to figure out where it is coming from.
First thing i have never seen the route Type code of 'L' before. Second thing i am not sure why the /32 L routes are showing up i only have the ip addresses defined on the interfaces with a /24.

Any insight would help as i think what ever is causing this may be the route of my Dynamic fail over isn't working.


S*    0.0.0.0/0 [130/0] via 172.31.105.1
      172.21.0.0/16 is variably subnetted, 4 subnets, 2 masks
C        172.21.1.0/24 is directly connected, GigabitEthernet0/0.1
L        172.21.1.1/32 is directly connected, GigabitEthernet0/0.1
C        172.21.2.0/24 is directly connected, GigabitEthernet0/0.100
L        172.21.2.1/32 is directly connected, GigabitEthernet0/0.100
      172.31.0.0/16 is variably subnetted, 2 subnets, 2 masks
C        172.31.105.0/24 is directly connected, GigabitEthernet0/1
L        172.31.105.2/32 is directly connected, GigabitEthernet0/1
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Question by:Steve262
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Predrag Jovic earned 333 total points
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L - means local ip address
/32 means just this IP address
172.21.1.1/32 is directly connected, GigabitEthernet0/0.1
In newer versions Cisco IOS Version 15.0(1)S and Cisco IOS-XR Version 4.3.1 has introduced L - local (I guess it is because of local link addresses of IPv6).
More:
http://www.cisco.com/c/en/us/support/docs/ip/ip-routing/116264-technote-ios-00.html
Sometimes you can have problems (in some configurations) if you have ip address on interface, and have subinterfaces configured (frame relay). And you have that in your configuration, but it also may mean nothing.
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by:Akinsd
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C        172.21.2.0/24 is directly connected, GigabitEthernet0/0.100  
The Network 172.21.2 is directly connected to Gig0/0.100

 L        172.21.2.1/32 is directly connected, GigabitEthernet0/0.100
The Local IP address on GIG0/0.100 is 172.21.2.1
As mentioned by Lovic, /32 refers to a single host.

Directly connected routes take precedence over static or learned routes as their AD is 0 (Default for Static is 1 or whatever AD value you assign to it)

Do a show run route, or show run | section ip route or just show run, and scroll down to the ip route section and post the result.
Static redundant routes will not show in the route table until the primary route fails. Post the show run (route section) and we'll go from there
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by:Steve262
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So i think what you guys are saying is this is just an idiosyncrasy of IOS 15.0 or above and that is why it may stand out compared to  what i have seen in the past.  

I am running OSPF on the router and using Weighted Static routes for fail over. I think there may be a separate issue entirely. I am assuming that both the local host directly connected route and the Directly connected network will go down if the link goes down. Correct?
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by:Predrag Jovic
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IOS 15.0 or above and that is why it may stand out compared to  what i have seen in the past.

Yes
I am assuming that both the local host directly connected route and the Directly connected network will go down if the link goes down. Correct?
In some cases yes, but it is not necessarily so, cable modem usually keeps directly connected network alive even if network behind cable modem is dead. So, that depends on design.
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