From: Annu (annu_roopa@xxxxxxxxx)
Date: Thu Dec 27 2001 - 12:15:46 GMT-3
Rajeev,
The question is like this...I am trying to compare
which routes take preference over which.
If u look at my fig. R5 is a ABr and getting two
external routes (E1 type)to same destination 20.1.1.1
one from ASBR(R4 cost=220) and another from another
ASBR-ABR path cost=94.The path between the two ABR is
NOT in AREA 0 (its in Area 1).
Now R5 takes the higher cost 220 path thru R4 instead
of low cost path thru ABR-ASBR.
So i am trying to understand and reason out why ??
this is happening.
Hope it helps.Let me know.
Annu
--- Rajeev Siddappa <raj_lab@yahoo.com> wrote:
>
> Hey Annu,
>
> The question is little confuing for me can you
> explain
> me in a different way. Or pls post the configs.
>
> Thanks,
> Rajeev.
>
> --- Annu <annu_roopa@yahoo.com> wrote:
> > Group,
> >
> > This is something i am unable to interpret.IF
> > someone
> > can tell me why this is happening ? Here goes the
> > scenario.
> >
> > e0 e0 s0
> >
> > R9------------------R11------R10--20.1.1.1
> > | <-area 0 ---------> |s1
> > s1 | |
> > R5------------------R4-------|
> > e0 e0 s1
> >
> >
> > R9/R5 are ABR's and connected to R11/R4( both
> > ASBR's)
> > E0 of both in area 0; Ser1 of ABR's in area 1.
> > R10 is connected to loopback 20.1.1.1.
> > R4 introduces type E1 route into R5.
> > R11 introduces type E1 route into R9.
> >
> > Cost of E0 on R5=200;all other interfaces have
> > default
> > cost.
> >
> > Now R5 gets two E1 routes,one with cost
> 220(200+20)
> > from R4 and other with cost 94(64+10+20)from R9.
> >
> > I thought the E1 route thru R9 and R11 will be the
> > preferred path as its same type and lower metric
> but
> > R5 seems to go thru R4.
> >
> > Am i wrong in understanding ? or what is missing ?
> >
> > Here are the route tables:
> > r5#show ip route
> > 55.0.0.0/16 is subnetted, 1 subnets
> > C 55.1.0.0 is directly connected, Serial1
> > O E1 20.0.0.0/8 [110/220] via 172.16.1.18,
> 00:03:11,
> > Ethernet0
> > 172.16.0.0/28 is subnetted, 1 subnets
> > C 172.16.1.16 is directly connected,
> Ethernet0
> > 192.168.1.0/28 is subnetted, 2 subnets
> > O E1 192.168.1.0 [110/220] via 172.16.1.18,
> > 00:03:11, Ethernet0
> > O E1 192.168.1.16 [110/220] via 172.16.1.18,
> > 00:03:11, Ethernet0
> >
> > When Ethernet fails ?
> >
> > r5#show ip route
> > Gateway of last resort is not set
> >
> > 55.0.0.0/16 is subnetted, 1 subnets
> > C 55.1.0.0 is directly connected, Serial1
> > O E1 20.0.0.0/8 [110/94] via 55.1.1.2, 00:00:23,
> > Serial1
> > 172.16.0.0/28 is subnetted, 1 subnets
> > O IA 172.16.1.0 [110/74] via 55.1.1.2,
> 00:00:23,
> > Serial1
> > 192.168.1.0/28 is subnetted, 2 subnets
> > O E1 192.168.1.0 [110/94] via 55.1.1.2,
> 00:00:23,
> > Serial1
> > O E1 192.168.1.16 [110/94] via 55.1.1.2,
> > 00:00:23,
> > Serial1
> >
> >
> >
> >
> > =====
> > Thanks in advance for ur time and replies.
> > Annu.
> >
This archive was generated by hypermail 2.1.4 : Thu Jun 13 2002 - 10:32:48 GMT-3