Airport randomly assigns IP address and stops working

[inscrewtable]

I have a netgear modem connected via ethernet to an airport extreme and an airport express extending the network.

I have been getting sudden wireless disconnection with the [!] symbol in the menu bar on the wireless indicator on my macbook pro. I eventually get it working again sometime just by going into diagnostics at other times it's more stubborn and I have had to reset my base stations. Sometime the base stations completely disappear from the airport utility.

Anyway, after dealing with this for a while and searching around I have narrowed the problem down but I don't know what is causing it, it seems to be isolated on my macbook pro.

I have noticed that when it stops working I will get a self assigned IP address instead of the usual 10.0.1.2

Strange thing is that when it happened last time my pod touch was connecting fine and airport utility on my ipod was indicated all was well, but the airport utility on the macbook pro was indicating a problem and would not connect.

I also notice when it happens that in the DNS pane of the advanced prefs the usual 10.0.1.1 disappears completely and the last time the problem occurred I put the 10.0.1.1 back and then it all kicked back in. So it looks like this works as a solution.

My question though, is what could be causing this behaviour which is only affecting the macbook pro? Why would it intermittently self assign an IP address and then not connect?

I am using the latest version of airport firmware. and 10.8.4

Any wisdom appreciated.

 

[tag]

First thing, you will always have a self assigned IP address when you get disconnected from and then are lacking an external source to distribute to you an IP address

Second, the only thing that comes to mind is some other device joins the network or renews an IP address and perhaps takes the address you are using? I've run into issues like this with Mac hardware now and then stealing IP addresses when they shouldn't.

To test this theory out, I would manually set a static IP address for you MacBook Pro, with a high enough IP address that would not be used by another device accidentally, such as 10.0.1.45 or something.

If you don't know how, to set a static IP address manually, go to Network Preferences > select Wi-Fi > select Advanced > select TCP/IP > under Configure IPv4 select "Using DHCP with manual address" > and then add in a static address like 10.0.1.45 etc.. ( you may now have to reconnect to the network again)

Verify through Network Preferences that you IP address is now the 10.0.1.45 or whatever you set it as, and if you find you are no longer getting kicked off the network, most likely some device on your network is stealing your assigned IP causing a problem. If you are still having issues, well, then I'm not real sure off hand. Maybe someone else will have an idea.

 

[inscrewtable]

OK thanks, I have tried that and all seems OK atm. There were a few visitors when this problem first manifested but it has carried on when they all left and there was only the mbp and ipod on the network.