Advice on routing/default gateways etc.

[zackboxer]

Sorry if this sounds abit like an exam question!!

(I'll call one network New York and one London for this example)

Routing protocol on both routers between London and NY is EIGRP

The machines in both sites are a mixture of 2000 and NT.

New York

Subnet 172.16.204.192/255.255.255.24

Router 172.16.204.193

Default Gateway 172.16.204.193

London

Subnet 172.16.205.0/255.255.255.0

Router 172.16.205.26 (connects to New York)

Router & Default Gateway 172.16.205.20 (connects to internet and email servers)

We have an existing network in London and want to connect the New York network.

New York has only one router which connects it only to London.

London however has a router to NY and also another router which is set as the default gateway.

The clients in London have internet access and the email server connects via this existing default gateway so this can't be changed.

If I set the gateway on the London clients to 172.16.205.26 I can connect to NY and vice versa but lose connection on the London clients to internet etc. If I leave the London default gateway as 172.16.205.20 then I can't connect between NY & London. I know you can put in more than one default gateway on the client machine's but in this instance that doesn't seem to work.

Also if I use static routes on the routers instead of EIGRP then I can connect without having to change the gateways on the London clients (but obviously want to avoid this and having to add hundreds of addresses manually!)

Just wondering if anyone has come across a similar problem and might have any idea's how I can resolve this??

Any suggestions would be gratefully received !!

Many thanks

[Georg Pauwen]

Hello,

can the two routers in London reach each other ? If so, you could use policy routing, which would send all traffic destined for New York to the interface pointing to New York, and all other traffic to the interface pointing to the Internet router. The config would look like this (assuming that New York is connected to interface serial0 and the Internet router to interface serial1, and your users are connected to interface FastEthernet0/0):

route-map TO_NEW_YORK permit 10

match ip address 101

set interface serial0

!

route-map TO_NEW_YORK permit 20

set interface serial1

1

access-list 101 permit ip 172.16.205.0 0.0.0.255 172.16.204.192 0.0.0.31 serial0

!

interface FastEthernet0/0

ip policy route-map TO_NEW_YORK

Or you could add static routes to the router connected to New York:

ip route 172.16.204.192 255.255.255.192 serial0

ip route 0.0.0.0 0.0.0.0 serial1

HTH,

Georg

[rajeshk200_2]

hai zac,

just add one static route on the router connected to new york.

ip route 0.0.0.0 0.0.0.0 172.16.205.20

no need to add multiple route statements.

i hope this will solve your problem

Regards,

rajesh

[rwcrowe]

rajesh is right, but if you log in and see that the route is already there or experience the same issues after the route has been added, it might be a redirect issue. If this is the case add "no ip redirects" under the FastE interface for the router connecting to New York.

[timm.benkula]

All you need to do is configure EIGRP on the London router (Router & Default Gateway 172.16.205.20). Then use show ip route on that router to verify that it has the route for your Subnet 172.16.204.192/255.255.255.24. Once you do this it won't matter which router you use for the default gateway in London. Each router will know the correct path for New York and the Internet.