Issued a Bad IP Address

Question

Issued a Bad IP Address

Hi guys,

I'm on a wireless network at work, and I'm getting issued a bad IP address. Windows users don't seem to be affected by this problem. Last night, I was able to look at a guy who's running Tiger on his laptop (and connecting to the internet fine), copy some of his settings and get onto the internet. I only changed the last three digits. So here's what I'm getting:

IP: 169.aaa.bbb.223
Router: 255.255.0.0

The computers that are getting onto the internet have a totally different IP issued:

IP: 192.xxx.yyy.105
Router: 255.255.255.0

Any ideas as to why this is happening? Today, I can't even enter the full address manually and get onto the internet. And two weeks ago (when I was last at work), I was getting on fine just using DHCP. I need an expert here!

I might also mention that all iPhones running the new 3.0 software are having the same problem.

Thanks,

Lawrence

Mac Pro 2 X 2.66 Xeon, Mac OS X (10.5.4)

Posted on Jul 27, 2009 5:37 PM

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Answer 1

xnav

Level 5

7,113 points

Jul 27, 2009 5:51 PM in response to Lawrence Ingram_Ii

255.255.0.0 is a subnet mask. The router address will start with either 169.aaa or 192.xxx.

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Answer 2

Jul 28, 2009 2:48 AM in response to xnav

Ah,

That's right! My router address starts with 169 for the bad address, and 192 if I'm getting online. What's the difference there? And how can I get back to using DHCP and getting issued a good address?

I should also note that I've been using Safari 4 beta, and I'm downloading the regular version now. I managed to get back online last night using a manual IP again.

Thanks,

Lawrence

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Answer 3

Jul 28, 2009 4:05 AM in response to Lawrence Ingram_Ii

A 169 IP address means that the machine was unable to get an IP address via DHCP so it assigned itself an address. You can't connect to a network while you have a self-assigned 169 IP address. You need to investigate an apparent connectivity problem that is preventing your machine from reaching the DHCP server.

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Answer 4

Jul 28, 2009 4:06 AM in response to Lawrence Ingram_Ii

Update:

After getting online with a manual address last night, I switched to DHCP, and left it. I got up this morning, installed the update Safari 4, and it seems to be issuing me a good IP using DHCP. I guess what I'm saying is that I'm not sure if it's because I got a good IP, then switched to DHCP, or because I installed Safari 4. But this may give others some things to try. I don't really understand networking that well.

Lawrence

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Answer 5

xnav

Level 5

7,113 points

Jul 28, 2009 8:42 AM in response to Lawrence Ingram_Ii

The version of Safari has nothing to do with IP assignment by DHCP. When you get the self assigned 169.x.x.x address then use Applications>Utilities>Console and check for network related error messages. Perhaps the wireless router is simply out of addresses to assign.

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Answer 6

Aug 18, 2009 6:35 AM in response to xnav

Ok,

Hopefully this helps someone. Yes, the router was limited in the number of IP addresses it could assign. I unplugged it (because people there just leave their laptops connected even when they are sleeping) knocking a few people off I guess, and then re-started my computer. After my keychain came up asking for my password, it did assign me a proper 192 IP address, and I was back online. I'm not sure why, but just unplugging the router didn't do it. It seemed like I HAD to restart the computer. Whatever the reason, it worked.

Thanks for all the help and suggestions.

Lawrence

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