I've got a home network running with a Linksys router. I've got one machine set up as a webserver, which has the address 192.168.1.101. I have my router set up to forward all incoming traffic on ports 80 and 22 to 192.168.1.101, so that people outside my network are able to access my webserver and SSH into the machine. However, it seems like every so often (several times a day), the machine will just randomly request a new address. I will attempt to SSH into the machine, only to discover that the machine now has the IP address 192.168.1.102, making it inaccessible from outside my network. I have no idea why this switch keeps happening, but it is causing many problems. The machine in question is running Debian Testing, with a default webserver installation.

Does anyone have any idea why this might be happening? Any help here will be greatly appreciated.

don't use DHCP on a server, that'd be my suggestion every time. alternatively reserve the IP address within the DHCP server.