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New Member

Basic Router Config- 1841 series

Hi All,

I am new to configuring Cisco Routers and the amount of commands and the terminology is dizzying. I need to configure the CISCO 1841 Router that I was provided to simply route between the two ethernet interfaces that it has. All of the documentation that I have found on this site seems to be for LAN/WAN routing or goes into router theory where multiple routers and networks are involved. This (at the moment) is simply two LAN networks that need to be connected.

Can someone point me to an example configuration such as this? or some documentation that explains how to setup a simple LAN to LAN interface for this router?

I have stumbled thru what I could and seem to have it working, but there is a problem with one device on one of the networks and it is the main reason for putting the router in in the first place. I have the following setup: a LAN at with several PC's and an ActiveDirectory Domain (win2003). a second Lan at with the problem device on it (when installed there are several other existing computers that will utilize this device (an embedded communication box that has an OEM version of XP)). When I put my laptop on the same as the comm box, I can ping the box on the same network and I can ping any computer on the other side of the router. From the other network, I can ping my laptop, but not the comm box? from the router CLI, I can ping the comm box with a standard ping, but if i use extended ping and source from the far interface, i get no response.

Any help would be appreciated.

Current Router Config is attached.

D Thune, MCSE


Re: Basic Router Config- 1841 series

Hi friend,

Here is the router configuration guide for 1800 series. Please go through the link and this should help you.

HTH, Please rate if it does.

-amit singh

Re: Basic Router Config- 1841 series

For a router to route between connected interfaces it only needs to have the interface IP's assigned. As long as the LAN devices are configured to have the router interface IP's as their default gateway it should all work ok. From your description it sounds like the comm box doesn't have it's default gateway defined correctly.



New Member

Re: Basic Router Config- 1841 series

Hi Andrew, this was the problem. Once we got the password to the Comm Box from their Tech Support, we were able to add the Default Gateway to it and the problem was solved. You were right on!


Re: Basic Router Config- 1841 series


Since SDM in configured on ur router, you can access the config through the web-browser


Try config-maker, a GUI configuration maker for entry level cisco config.

Pls rate all posts



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