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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.

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migrated from Feb 14 '12 at 13:49

This question came from our site for system and network administrators.

Dynamic or static IP? Verified that the no other systems are contending for the same IP? Checked the logs on your web server? – Tim Brigham Feb 12 '12 at 15:01
I'm using DynDNS with a dynamic IP and DHCP for the LAN. The following line is repeated many times in my modem/router's log: DHCPINFORM from (my server is And I forgot to mention that Debian cannot access anything other than localhost. – Linksku Feb 12 '12 at 15:37
I doubt your ISP has anything to do with this if Windows is working fine. That's elementary troubleshooting. What system are you getting your DHCP information from? Do you administer it? – Magellan Feb 12 '12 at 21:42
I getting DHCP info from the modem/router from Bell Canada. I reinstalled Debian, then I lost Internet access again after a while. Before the Internet access broke, I installed UFW, Lynx, and ZIP. – Linksku Feb 13 '12 at 0:05

How are you configuring your network? Is it via a tool like network manager or is it directly in /etc/network/interfaces?

It might be possible that one is trying to reconfigure the other periodically.

If you're using it as a server, I would recommend configuring it via /etc/network/interfaces and uninstall/disable network manager or the like.

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Everything is default. Here's my interfaces file: auto lo\n iface lo inet loopback\n allow-hotplus eth0\n iface eth0 inet dhcp – Linksku Feb 12 '12 at 17:21

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