Howto Show RIB and FIB ?

Hi all,

I'm currently looking for a command on the Cisco to see the FIB and RIB.

The "show ip route" command only displays the FIB. I made two static entries in the RIB for the same net reached on two different interfaces with different metrics. How can I see the actual RIB ? I don't want to see the config file, I know that this is a way to find it out, but thats not the point for me.

Cheers, Fr=E9d=E9ric

P=2ES.:

----> Entries in config file ip route 10.0.0.0 255.0.0.0 Serial0 30 ip route 10.0.0.0 255.0.0.0 Ethernet0 40

Reply to
frederic.metz
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You got it backwards.

RIB - show ip route FIB - show ip cef, show adj

snipped-for-privacy@gmail.com wrote:

Reply to
Todd Sinclair

Installed routing entries from RIB seen via sh ip route.

AFAIK there is no command in IOS to see "backup" routes (i.e the static route with admin distance = 40

Reply to
Merv

Thanks for the help,

but Cisco Express forwarding seems a special Forwarding Thing in Cisco Routers. It is turned off on my Cisco ("%CEF not running" on both of your commands).

So the RIB is the Table which is build up by Routing Protocols or static Routes. It could have the same entry for reaching one network with the corresponding metrics. The FIB has only one entry per network, the FIB is gerated (as a subset) by the RIB, the FIB tuples are unique. --> the "sh ip route" command has only one entry for the destination network, so it is the forwarding table (from the FIB). I see many people saying "Routing table" when they talk about the forwarding table. But I'am a bit abroad this moment.

I want to see the both tables. sh ip route is the one, how can I see the other. CEF is not enabled. The 2 entries are in the config and they work.

///// S 10.0.0.0/8 is directly connected, Serial0

after pluggin' out the serial cable, the FIB is new calculated, it takes abut 10 seconds and then:

///// S 10.0.0.0/8 is directly connected, Ethernet0

So where the hell is the RIB ? :-)

Thanks and cheers ,, Fr=E9d=E9ric

Reply to
frederic.metz

but Cisco Express forwarding seems a special Forwarding Thing in Cisco Routers. It is turned off on my Cisco ("%CEF not running" on both of your commands).

So the RIB is the Table which is build up by Routing Protocols or static Routes. It could have the same entry for reaching one network with the corresponding metrics. The FIB has only one entry per network, the FIB is gerated (as a subset) by the RIB, the FIB tuples are unique. --> the "sh ip route" command has only one entry for the destination network, so it is the forwarding table (from the FIB). I see many people saying "Routing table" when they talk about the forwarding table. But I'am a bit abroad this moment.

I want to see the both tables. sh ip route is the one, how can I see the other. CEF is not enabled. The 2 entries are in the config and they work.

///// S 10.0.0.0/8 is directly connected, Serial0

after pluggin' out the serial cable, the FIB is new calculated, it takes abut 10 seconds and then:

///// S 10.0.0.0/8 is directly connected, Ethernet0

So where the hell is the RIB ? :-)

The routing table - show ip route - is your FIB. (forwarding based upon 'best' pathways)

There is no command that explicitly shows the RIB, which is the collection of all routing information learned. (best - worst - and in between pathways)

You can indirectly learn what is in the RIB by debuging and looking at topology data bases.

For instance, you can debug rip and see what each of your neighbors is advertising to you. Or, you can look at the OSPF data base and try to interpret its contents. But there is no single command that tells you "these are all the pathways that I have learned from all neighbors," with the exception of the BGP table, which is essentially a RIB data base. (show ip bgp)

-ja

Reply to
John Agosta

Okay, thanks a lot.

Reply to
frederic.metz

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