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Frame-relay Confusion, [7:131581] posted 06/19/2008
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hi all, i am confused with a very basic scenario so kindly guide me, this
post will be a bit long so kindly bare it :)
i have 3 routers R1, R2, R3 connected via frame-relay network in hub n spoke
topology. R1 is the hub, R2,R3 are spokes. Their relative configuration is
given below
R1 
int se 1/0
en frame-relay
no frame-relay inverse-arp
ip address 11.0.0.1 255.0.0.0
frame-relay map ip 11.0.0.2 102 broadcast <-- to R2
frame-relay map ip 11.0.0.3 103 broadcast <-- to R3

int lo 0
ip add 1.1.1.1 255.0.0.0

router rip
ver 2
no auto
net 11.0.0.0
net 1.0.0.0

On R2 and R3 similar configuration is present with frame-relay map pointing
to 11.0.0.1 broadcast and running rip.
R2 loopback 2.2.2.2/8
R3 loopback 3.3.3.3/8

now i can see routes at R2 via rip

R 3.0.0.0/8 [-/-] via 11.0.0.3, serial 1/0

when i ping 3.3.3.3 from R2 and do debug i can see encapsulation failed,
since 11.0.0.3 is not present in the frame-relay map command, so far its
cool, no confusion at all. now see wht are my concepts of next hop resolution,
to go to 3.3.3.3 
sh ip route 3.3.3.3
it will show next hop of 11.0.0.3
to reach 11.0.0.3
its showing directly connected via se 1/0
it will look for layer 3 to layer 2 mapping which is not present hence encap
failed.
now this is wat i did to solve the issue ( which is my actual confusion )
i gave an static route
ip route 11.0.0.3 255.255.255.255 11.0.0.1
now when i again performed lookup see wat happened !
sh ip route 3.3.3.3
reach via 11.0.0.3
sh ip route 11.0.0.3
reach via 11.0.0.1
sh ip route 11.0.0.1
direclty connected via Se1/0

now if i ping 3.3.3.3 it fails !!, if i only change the route to this one
ip route 3.3.3.3 255.255.255.255 11.0.0.1
now ping is successful, 

Can some1 really explain me why it didnt happen in the previous route ? when
i have told the router that 11.0.0.3 is reachable via 11.0.0.1 whose mapping
is present in the map table then why didnt it succeeded ??

Kindly explain me this in a convincing manner since i m really confused (
couldnt sleep last night ! )




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