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Replacing two routers with a single (multi)modular one: help with routes

Hi,

I need to replace a cisco 837 (connected to an adsl circuit) and a

1720 (connected to an HDSL circuit via a serial modem) with a new 1841 having 2 WICS (Adsl and serial).

The 837 and the 1720 are perimeter routers, used by an internal router and a couple of PIX firewalls to manage a few VPNs. So it's important that the new 1841 will work exactly as the 837 and the 1720.

I post below the relevant parts of the 837 and 1720 configs, plus a tantative config of the 1841.

My problem is how to manage the (default) routes on the new 1841... can you point me to the right direction please? Any help is greatly appreciated

Thanks in advance Guido

837 (manages ADSL circuit)

---------------------------- interface Ethernet0 ip address aaa.aaa.aaa.aaa 255.255.255.248 hold-queue 100 out !! interface ATM0 no ip address no atm ilmi-keepalive dsl operating-mode auto hold-queue 224 in ! interface ATM0.1 point-to-point bandwidth 1280 ip address bbb.bbb.bbb.bbb 255.255.255.252 no snmp trap link-status pvc 8/35 encapsulation aal5snap ! ! interface FastEthernet1 duplex auto speed auto ! interface FastEthernet2 duplex auto speed auto ! interface FastEthernet3 duplex auto speed auto ! interface FastEthernet4 duplex auto speed auto ! ip forward-protocol nd ip route 0.0.0.0 0.0.0.0 ATM0.1

1720 (manages HDSL circuit)

---------------------------- interface FastEthernet0 bandwidth 100000 ip address xxx.xxx.xxx.xxx 255.255.255.248 speed auto ! interface Serial0 bandwidth 256 no ip address encapsulation frame-relay IETF ! interface Serial0.1 point-to-point bandwidth 2048 ip address yyy.yyy.yyy.yyy 255.255.255.252 no arp frame-relay no cdp enable frame-relay interface-dlci 345 IETF ! ip classless ip route 0.0.0.0 0.0.0.0 Serial0.1

1841 (new router with WIC ADSL & serial WIC x to replace both 837 and 1720)

------------------------------------------------------------------------ interface FastEthernet0/0 description ** replaces 1720 FastEthernet0 ** bandwidth 100000 ip address xxx.xxx.xxx.xxx 255.255.255.248 speed auto ! interface FastEthernet0/1 description ** replaces 837 Ethernet0 ** bandwidth 100000 ip address aaa.aaa.aaa.aaa 255.255.255.248 speed auto ! interface Serial0/0/0 bandwidth 256 no ip address encapsulation frame-relay IETF ! interface Serial0/0/0.1 point-to-point description ** replaces 1720 serial0.1 ** bandwidth 2048 ip address yyy.yyy.yyy.yyy 255.255.255.252 no arp frame-relay no cdp enable frame-relay interface-dlci 345 IETF ! interface ATM0/1/0 no ip address no atm ilmi-keepalive dsl operating-mode auto hold-queue 224 in ! interface ATM0/1/0.1 point-to-point description ** replaces 837 ATM0.1 ** bandwidth 1280 ip address bbb.bbb.bbb.bbb 255.255.255.252 no snmp trap link-status pvc 8/35 encapsulation aal5snap ! ip classless ip route ---> *** how should I set this to have this 1841 behave exactly as 1720+837? ***

Reply to
gb
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If I understand this correctly, your going to have 1 router, 2 different circuits and you need to route traffic out different interfaces based on the circuit it should route. If that is correct you can use policy based routing to route by source address.

iF i did not understand you correctly then please clarify.

Reply to
Techno_Guy

Yes, I need to do exactly that.

To clarify further: if a packet enters the 1841 from interface FastEthernet0/0 then send it out to Serial0/0/0.1 if it enters from FastEthernet0/1 then send it out to ATM0/0/0.1

Could you please help me with the commands and the syntax I should use to implement policy based routing in my specific case?

Thanks in advance Guido

Reply to
gb

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Here ya go.

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Either website will tell you just what to do. Good luck and let me know if you dont understand. I think howerver, after reading these links you will be in good shape.

Reply to
Techno_Guy

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