Strange DHCP Problem

[RAC]

My iPad has worked for 9 months on dynamic DHCP, suddenly, today, it stopped working. There was a tick next to the router in WiFi Settings but no wireless icon at the top left of the screen. The other strange thing was that the IP address was 169.xxx.xxx.xxx not 192.xxx.xxx.xxx as it should have been. No other other computers or devices had network problems.

The only fix seemed to be to assign a static IP on the router (linked to the iPad MAC address) and the iPad.

Can anyone explain what is going on here?

I had not made any changes on the router or the iPad by the way.

 

[LannyC]

I can't explain your issue, but I've been a lot happier since I assigned fixed addresses to our LAN's two iMacs, two iPads, and a printer. Just do it.

This post handcrafted from 100 percent post-consumer recycled electrons.

 

[twerppoet]

The usual fix is to reboot the router, then (while the router is down) to got Settings > General > Reset, and reset the network settings on the iPad. Routers can get temperamental about specific devices (while the others keep working fine), and iPads are notorious for being caught out this way. You should also check to make sure your router is up to date in it's firmware, as this often solves the problem long term.


LannyC's static solution is a surer workaround, but it requires more work, and if you are smart, some basic record keeping, so that you don't spend too much time settings things up again if the iPad forgets the network for some reason; or you have to configure your router again (since static addresses should be reserved to each device's MAC address (ideally).

 

[RAC]

Thanks for the replies. I think that I will just stay with static IP. If that's answer, I am happy with that.

Until a couple of years ago, I always used static IP and MAC filtering. When the number of wireless devices in the house went past 10, I got lazy and started to rely on DHCP.

It's strange how this problem just appeared from out of the blue though.

 

[the damps]

Verrrry interesting. DW's iPad went south a couple of days ago with similar symptoms. I initially blamed it a problem with our Xfinity router/modem, which had shown some instability (doing self-triggered restarts). We were getting some websites (Facebook and e-mail) but couldn't get anything through Safari. I went to a computer shop's wifi and couldn't get anything on their hotspot either.

Since I'm a long-term Windows guy (still - with a desktop) and have only had the iPad since August, I wasn't sure what the problem was.

I'll retrieve it from the shop and check this problem out.

Incidentally, I couldn't get to the APP store through its icon.

Frank Damp

 

[Spugnut]

With the adress ranges changing so dramatically, It could be that the router sessting have been reset to factory default. I had that happen to me some time ago after a power failure. the only solotion was to restore the router settings from a backup, or conficuring it manually.

 

[Tudor]

A 169.x.x.x range address is what gets assigned when the device can see a network, but there is no DHCP server giving out addresses. I have only ever seen it before on a "windows" desktop machine.

 

[the damps]

A quick follow-up to my earlier post. The repair guy found that the area where the computer remembers wi-fi neworks it had connected to, it contained a large number of hot spots recorded from all over Washington, Oregon and Idaho. He went through and told it to forget each one in turn, leaving just the shop's link and the keyboard's Bluetooth address active and the computer made a full recovery.

When I asked my daughter if she'd used it for her work (she travels extensively) she said the records were probably from hotels and work-places where she'd used it.

 

[twerppoet]

On the iPad you can do this in one step. Go to Settings > General > Reset, and Reset Network Settings.

You can forget individual networks in Settings > Wi-Fi, by tapping the (i) icon by the network and choosing Forget this Network. If you were talking about your iPad (it's unclear from the post since you said computer), this is probably what the repair guy did.