I'm trying to set up a Debian box for running MythTV, and for some reason it won't hold the network connection. It's configured with a static IP gateway'd through my router, and it works fine for connecting out - web browsing, telnetting out, etc. all work fine. Nothing can connect to *it* though, even though I know I have the mysql server running and can connect to it locally.

Edit to explain - I mean, nothing can connect within my network. It's not supposed to be accessible from the Internet, and the router isn't set to forward anything to it. The problem is that I can't connect to it from within the network.

My router has a section for "attached devices", which lists every device connected to the network. If I browse to a web page with the mythbox, then it shows up in the connected devices list; but after less than a minute it appears to time out, and no longer shows that it's connected. Everything else on the network is shown in the list, regardless of whether it's actually communicating with anything or not, so it's acting as though the cord was actually pulled from the mythbox. Even when it is being shown in the list though, I can't ping it or connect to mysql or anything.

If anyone knows what could cause this, any help would be appreciated.. also this is my first time installing Linux in ages and I've had to do everything through X as I don't really know the config files and such yet, so if you have any advice, please explain it as if I were a small child. :o Thanks!

Running Kernel version 2.4.27-2-386
Athlon 1200mhz, 3Com 3c905 NIC
If you need any other info, just ask..