I've got a really strange problem. I'm running Debian Etch on one of the three computers in my home network. Everything was running fine earlier, but I just went to check on it before I went to sleep, and noticed that I wasn't seeding my torrents - and gaim wasn't connected. I had lost my connection to the internet!

I decided to ping one of the other computers on my network and met with success. Strangely, though, if I try to ping the router between the two computers, it won't work. I've double and triple checked the numbers - no dice. I can't understand how it could ping two other network computers and localhost, but nothing else *including* the router.

I'm using OpenDNS on all three computers, including the one I'm writing this post with. I've ruled it out as a problem, since it's working fine on the two other machines.

The part that worries me... I've got Ubuntu on one of my other partitions. It has the same problem. I loaded up a live disc of Puppy Linux - same problem. Uh oh. I'm thinking my network card is fried. I was hoping that the live disc would connect fine, which would lead me to believe that it was just a messed up setting.

Any other suggestions? How could I possibly see another network computer that's attached to the router, but not the router itself?

EDIT: Update! I wanted to try something completely different as a last resort (for tonight, anyway) and put in a NetBSD Live disc. I've got a connection to the net... I'm writing to you via NetBSD on the affected computer. Hmmm... well, back to Debian - after a good night's sleep, anyway!

Odd... does the router accept pings from other clients? Some routers do not allow pings at all.

As to your original problem: any chance the router is blocking you? Or maybe you have odd routing tables?

Thank you for your reply, Matir!

The router does accept pings from other clients.

This morning, I went into Debian and switched the network configuration from static to DHCP and the internet immediately began to work. It can also see my router now.

So, given my low level of network understanding, it seems like my router might be blocking the internal IP of the one computer (since I've got it set for DHCP addresses to begin as slightly higher numbers). I've got a fairly common D-Link DI-604 and just went through each page and option in detail - everything seems to be in order. Does anybody have any ideas of specific places to look?

UPDATE: I tried pinging from my router (via the web interface) to my problem computer and it didn't work. Thinking that that was really strange, I rebooted my router and everything seemed to work! Moral of the story: when in doubt, reboot the router.