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So I recently set up an apache server on Ubuntu 11.04 in my apartment. I plug directly into the wall and I know that this goes to a router because I can connect to it via I set up port forwarding and everything was running smoothly until the next day. The server was down and when I did an ifconfig I found that the ip had changed to 66.XX.XXX.XXX wheres the day before it was 69.XX.XXX.XXX. I am not able to connect to the router. When I unplug and re plug it into the wall port I get a 192 number for a day then it changes again. Is there anything that would of caused the ip to change and is there a way to fix it?

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up vote 2 down vote accepted

To begin with, this is hard to say for sure due to the ips in the example.

66.x.x.x and 69.x.x.x would be in completely different ranges and even if your ISP has a few different IP blocks, something seems not right here as you should have not been able to connect to your router on so I am a little confused as to what is going on.

My guess is one of the following:

  1. You are connected to a different router.
  2. The router has bridged mode on some ports.
  3. You have multiple routers.
  4. (sort of combined with 3) - the wiring at your apartment is not straight forward and it is ending up in the wrong port.

All this being said, unless you are using static IP addresses, if a machine is not on when the DHCP lease expires, it is possible to loose your reservation and that IP address.

I hope this helps a little, but, again, it sounds a little weird from what you have said and to help you further, I really need to know more about your network topology.

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