From: Nick Lesewski (nickless9@xxxxxxxxxxx)
Date: Tue Jun 04 2002 - 14:45:47 GMT-3
I wanted to pass the solution to this little puzzle back to the group to
help anybody who is following this thread and, like me, didnt know the
answer. (see the message below this thank you note)...
Thank you Clay, Micheal, Brian and Georg for so quickly giving me the answer
to something that was kicking my butt for several hours last night
Excellent group response
NIC
>From: Clay Maney <clay@openworldinc.com>
>To: Nick Lesewski <nickless9@hotmail.com>
>Subject: Re: routing protocol puzzle
>Date: Tue, 4 Jun 2002 13:37:02 -0400
>
>on the loopback0 interface, do a ip ospf network-type point-to-point
>and then it'll pass the actual mask of the interface (/24 in this case)
>instead of using the host route. Otherwise, it'll always use the host
>route for OSPF.
>
>HTH,
>Clay
>
>On Tue, Jun 04, 2002 at 10:09:05AM -0700, Nick Lesewski wrote:
> > I've been playing with AD and I've got something confusing. I've got
>six
> > routers layed out like this:
> >
> > R2---R3
> > / \
> > R1 R6
> > \ /
> > R4---R4
> >
> > Routers R2 and R3 are only running EIGRP.
> > Routers R4 and R5 are only running OSPF.
> > Routers R1 and R6 are running both.
> > There is no redistribution between the two protocols.
> > R6 has a loopback interface that is being advertised through a network
> > statement in each of the two protocols.
> >
> > I would expect R1 to see the loopback on R6 through both protocols, but
>then
> > selected EIGRP, since it has a lower AD. What happens is that OSPF
>provides
> > a /32 route that takes precidence over the /24 route provided by EIGRP.
>It
> > seems like OSPF is finding the specific address of the loopback
>interface,
> > while EIGRP is finding the whole class-C network, so OSPF is taking
>control.
> > My question is... why?
> >
> > Here are my configs...
> >
> > R1#show run
> > Building configuration...
> >
> > Current configuration:
> > !
> > version 12.0
> > service timestamps debug uptime
> > service timestamps log uptime
> > no service password-encryption
> > !
> > hostname R1
> > !
> > no logging console
> > enable password cisco
> > !
> > ip subnet-zero
> > no ip domain-lookup
> > !
> > interface Loopback0
> > ip address 192.168.1.1 255.255.255.0
> > no ip directed-broadcast
> > !
> > interface Serial1/0
> > ip address 192.168.14.1 255.255.255.0
> > no ip directed-broadcast
> > encapsulation ppp
> > no ip mroute-cache
> > no fair-queue
> > !
> > interface Serial1/1
> > ip address 192.168.12.1 255.255.255.0
> > no ip directed-broadcast
> > encapsulation ppp
> > !
> > router eigrp 21
> > network 192.168.1.0
> > network 192.168.12.0
> > !
> > router ospf 12
> > network 192.168.1.0 0.0.0.255 area 0
> > network 192.168.14.0 0.0.0.255 area 0
> > !
> > ip classless
> > no ip http server
> > !
> > alias exec i show ip route
> > alias exec co config t
> > !
> > line con 0
> > exec-timeout 0 0
> > password cisco
> > login
> > transport input none
> > line aux 0
> > exec-timeout 0 0
> > password cisco
> > login
> > line vty 0 4
> > exec-timeout 0 0
> > password cisco
> > login
> > !
> > end
> >
> >
> > R2#show run
> > !
> > interface Loopback0
> > ip address 192.168.2.2 255.255.255.0
> > !
> > interface Serial0
> > ip address 192.168.23.2 255.255.255.0
> > encapsulation ppp
> > no ip route-cache
> > no ip mroute-cache
> > clockrate 125000
> > !
> > interface Serial1
> > ip address 192.168.12.2 255.255.255.0
> > encapsulation ppp
> > no ip route-cache
> > no ip mroute-cache
> > clockrate 125000
> > !
> > router eigrp 21
> > network 192.168.2.0
> > network 192.168.12.0
> > network 192.168.23.0
> > auto-summary
> > no eigrp log-neighbor-changes
> >
> >
> > R3#sh run
> > !
> > interface Loopback0
> > ip address 192.168.3.3 255.255.255.0
> > !
> > interface Serial0
> > ip address 192.168.23.3 255.255.255.0
> > encapsulation ppp
> > no ip route-cache
> > no ip mroute-cache
> > !
> > interface Serial1
> > ip address 192.168.36.3 255.255.255.0
> > encapsulation ppp
> > no ip route-cache
> > no ip mroute-cache
> > clockrate 125000
> > !
> > router eigrp 21
> > redistribute connected
> > network 192.168.23.0
> > network 192.168.36.0
> > default-metric 1000 10 1 255 1500
> > auto-summary
> > no eigrp log-neighbor-changes
> >
> >
> > R4#sh run
> > !
> > interface Loopback0
> > ip address 192.168.4.4 255.255.255.0
> > no ip directed-broadcast
> > !
> > interface Serial0
> > ip address 192.168.14.4 255.255.255.0
> > no ip directed-broadcast
> > encapsulation ppp
> > no ip mroute-cache
> > clockrate 125000
> > !
> > interface Serial1
> > ip address 192.168.45.4 255.255.255.0
> > no ip directed-broadcast
> > encapsulation ppp
> > !
> > router ospf 12
> > network 192.168.4.0 0.0.0.255 area 0
> > network 192.168.14.0 0.0.0.255 area 0
> > network 192.168.45.0 0.0.0.255 area 0
> >
> >
> > R5#sh run
> > !
> > interface Loopback0
> > ip address 192.168.5.5 255.255.255.0
> > !
> > interface Serial0
> > ip address 192.168.56.5 255.255.255.0
> > encapsulation ppp
> > clockrate 125000
> > !
> > interface Serial1
> > ip address 192.168.45.5 255.255.255.0
> > encapsulation ppp
> > clockrate 19200
> > !
> > interface BRI0
> > ip address 170.12.26.254 255.255.255.252
> > encapsulation ppp
> > !
> > router ospf 12
> > log-adjacency-changes
> > redistribute connected metric 100 subnets
> > network 192.168.45.0 0.0.0.255 area 0
> > network 192.168.56.0 0.0.0.255 area 0
> >
> >
> > R6#sh run
> > !
> > interface Loopback0
> > ip address 192.168.6.6 255.255.255.0
> > !
> > interface Serial0
> > ip address 192.168.56.6 255.255.255.0
> > encapsulation ppp
> > !
> > interface Serial1
> > ip address 192.168.36.6 255.255.255.0
> > encapsulation ppp
> > !
> > interface BRI0
> > ip address 170.12.26.253 255.255.255.252
> > encapsulation ppp
> > !
> > router eigrp 21
> > network 192.168.6.0
> > network 192.168.36.0
> > auto-summary
> > no eigrp log-neighbor-changes
> > !
> > router ospf 12
> > log-adjacency-changes
> > network 192.168.6.0 0.0.0.255 area 0
> > network 192.168.56.0 0.0.0.255 area 0
> > !
> >
> > Any help in understanding what's going on is appreciated...
> >
> > Thanks...
> >
> > NIC
> >
> >
This archive was generated by hypermail 2.1.4 : Tue Jul 02 2002 - 08:12:23 GMT-3