I just set up a Debian machine to use as a web server. However, it would randomly lose Internet access for a while, then be fine a few minutes later. Other computers on the same network are fine. I tried a different Ethernet cable, but that's not the problem either. I had Ubuntu on the machine before and the Internet was fine. I can't even SSH the machine on LAN.
What could be the cause? My ISP is Bell Canada and I have DSL.
Edit: Also, I can't access any websites or any devices on LAN from Debian.