Need a simple routing config for a Cisco 871

[paccorobin]

Can someone please help me? I need a very simple routing config for a Cisco 871.

On the WAN side I have an IP address that is in the same network as my DSL modem. On the LAN side I have an IP address that is in the same network as my ASA.

Right now I use a pc with two NICs and that works ok. But when I connect the 871 traffic is dropped.

This is the config I put in (please don't laugh, I am no expert at all with IOS):

hostname Cisco871
interface FastEthernet0
interface FastEthernet1
interface FastEthernet2
interface FastEthernet3
interface FastEthernet4
ip address xxx.xxx.xxx.xxx 255.255.255.252
duplex auto
speed 10
interface Vlan1
ip address yyy.yyy.yyy.yyy 255.255.255.248
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 xxx.xxx.xxx.xxx-1

What am I doing wrong?

Regards and thanks!

Frank

 

[unclerico]

is the ASA the gateway for your pc's??

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[paccorobin]

Yes, I have a SDSL line with a Siemens modem. Then I want to use the 871 as a router, then the ASA as firewall and gateway for my internal network. ASA takes care of NAT etc.

Regards,

Frank

 

[unclerico]

so do you have a public ip range between the 871 and the ASA also??

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[paccorobin]

Yep, public between modem and 871 (Point-to-Point according to supplier/255.255.255.252) and public between the 871 (255.255.255.248) and the outside of the ASA.

The supplier told me the line was delivered with only a modem and I had to take care of a router myself.

 

[unclerico]

ok, so the ASA needs to have a default route pointing to the 871 and NAT configured. as far as routing is concerned, the 871 needs nothing more added.

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[paccorobin]

The ASA has a default route and that works. ASA translates public ip addresses to internal addresses and also for outgoing traffic.

Right now the ASA is hooked up to a pc with NIC lan with a public ip address and that's the gateway for the ASA. This pc has another NIC wan and that's the point to point public ip address and for this NIC I filled in the gateway (being the SDSL modem). For the NIC lan I left the gateway blank.

 

[unclerico]

when you swap the pc for the 871 reboot the modem

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[paccorobin]

So you think my config is ok and needs no more adjustments?

I will try this somewhere this week when no users are in and I can go to the office.

Thanks.

 

[unclerico]

yes, i think your config is ok. i believe the issue is with the modem. make sure it is not in bridge mode and that it is the device that contains the credentials required to establish your DSL connection

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[paccorobin]

OK, connected the router. Turned off the modem AND the ASA. Turned on the router, afterwards the ASA and the modem.

Guess what, works like a charm.

Thanks very much Unclerico.

Regards,

Frank

 

[unclerico]

good deal. glad to help.

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[burtsbees]

Give him a star for all his posts, dude...

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