cisco router redirect 1

[wannabie2]

I have a cisco router 1860 that I use for a small business. it's an older model but it works.
the other day someone plugged in a linksys router into the network to test something he was working on and he knocked everyone out of the system.

both routers are all pointing to 192.168.1.1 I have two questions.

why did his router take precedence over mine?
how do I prevent this?

 

[stubnski]

==> someone plugged in a linksys router into the network to test something he was working on and he knocked everyone out of the system.

With so little information on your network setup I am assuming the linksys router was plugged in backwards so it was advertising itself as a DHCP server or it duplicated the IP address of one of your network devices. If this is the case you have two options:

1: Beat the person who plugged in a home router on their own with said router (mandatory)
2: I'm not sure what version of software you have for your access switches but dhcp snooping is a must in any DHCP environment.

 

[wannabie2]

Thanks. this maybe is what I need.

Will configure DHCP snooping on my router.