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Basic lab config - where is my default route wrong

I have two 2501s that I am playing with for CCNA lab exercises. BHM is the router connected to the Internet gateway (the gateway's internal address is 192.168.0.3). The problem I am experiencing is that I cannot get to the Internet from GAD (see configs below), though I can from BHM:

========================= sho run BHM#sho running-config ! version 12.2 ! ip subnet-zero no ip domain-lookup ! interface Ethernet0 ip address 192.168.0.80 255.255.255.0 ! interface Serial0 ip address 172.17.0.2 255.255.0.0 clockrate 56000 ! router rip version 2 network 172.17.0.0 network 192.168.0.0 ! ip classless ip route 0.0.0.0 0.0.0.0 192.168.0.3 ============================== sho run GAD#sho running-config

version 12.2 ! ip subnet-zero no ip domain-lookup ! interface Ethernet0 ip address 172.16.0.1 255.255.0.0 ! interface Serial0 ip address 172.17.0.1 255.255.0.0 ! router rip version 2 network 172.16.0.0 network 172.17.0.0 ! ip classless ip default-network 192.168.0.0

===========================

From GAD I can ping 192.168.0.80, which is BHM's e0 on the same network

as the Internet gateway. But I can get no further than that interface (cannot ping 192.168.0.3). From BHM I can ping anywhere on the Internet.

Please help me make sense of this.

Thanks

-tom

Reply to
evergladesfl
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"If the router has a directly connected interface onto the specified network, the dynamic routing protocols running on that router will generate (or source) a default route. For Router Information Protocol (RIP), this is flagged as the pseudonetwork 0.0.0.0; for Interior Gateway Routing Protocol (IGRP), it is the network itself, flagged as an exterior route."

If this is the entire configuration, then your router GAD has no need to source a default route (which would be sent to other routers). Even if it does need to generate a default route via rip, it has no directly connected interface to the 192.168.0.0 network as required.

For your purposes I think a simple "ip route 0.0.0.0 0.0.0.0

172.17.0.2" would work best.

I would also change the mask on your serial interfaces to

255.255.255.252, but that's just me. They should work OK as specified.
Reply to
erik.freitag

Thanks for the reply. I have not yet used the the ip route 0.0.0.0

0.0.0.0 172.17.0.2 command you suggest, but will give it a go.

One thing that I still do not understand is why GAD cannot get to the address 192.168.0.3, since it does have a route to 192.168.0.0 and can get to 192.168.0.80 (e0 on BHM).

Could you help me understand this?

Thanks snipped-for-privacy@pobox.com wrote:

Reply to
evergladesfl

So does the internet gateway on 192.168.0.3 have a route back to GAD via the BHM router?

Chris.

Reply to
chris

Crap - that's it!

Thanks!

chris wrote:

Reply to
evergladesfl

Reply to
ramesh51281

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