DHCP randomly stops giving IP's to wireless devices - APIPA

[davida1992]

Hi, before anyone asks I have tried using several different routers from BT to resolve this issue with no luck.

Ill try to paint a picture first!

We have our main Router provided by BT (Business Hub 3). The hub is connected to a switch, the switch goes out to all wired devices on the network. 

The switch has a couple of wireless access points plugged into it as we have a large site, the access points across the site (including the main router) all have different channels selected and only just overlap each other. When everything works devices seem pretty good at switching from one AP to another if one goes out of range. All AP's have the same SSID, password and security type etc so roaming seems to work (when it works! )

DHCP is disabled on all AP's and the BT router, we used Windows Server 2008 R2 running DHCP and DNS services.

Everything seems fine but when people come for lunch after roaming around the site, some may and some may not have internet access, all wireless devices such as iPads and phones, wired devices never have an issue!

After insepcting the devices they seem to end up with a 169 address and i have no idea why!

Sometimes when the router is switched off and on again it starts working again which i find even more strange since DHCP is not in use on it.

I have gone onto Windows Server and looked at the DHCP logs, and it seems a lot of people are having their leases renewed every few seconds, not sure if this is normal, or what could be causing it. DHCP leases are set to 8 days on the server.

A small portion of the DHCP log is below, you can see what it is doing sometimes.

Please help! 🙂

11,12/03/13,12:30:21,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,1904021297,0,,,
11,12/03/13,12:30:23,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,1904021297,0,,,
11,12/03/13,12:30:55,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,3738532478,0,,,
11,12/03/13,12:30:58,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,3738532478,0,,,
24,12/03/13,12:41:45,Database Cleanup Begin,,,,,0,6,,,
25,12/03/13,12:41:45,0 leases expired and 0 leases deleted,,,,,0,6,,,
25,12/03/13,12:41:45,0 leases expired and 0 leases deleted,,,,,0,6,,,
11,12/03/13,13:20:13,Renew,192.168.1.101,Mattys-iphone.woodlands.farm,78CA398EBABD,,1928272809,0,,,
11,12/03/13,13:20:14,Renew,192.168.1.101,Mattys-iphone.woodlands.farm,78CA398EBABD,,1928272809,0,,,
11,12/03/13,13:20:17,Renew,192.168.1.101,Mattys-iphone.woodlands.farm,78CA398EBABD,,1928272809,0,,,
11,12/03/13,13:22:07,Renew,192.168.1.101,Mattys-iphone.woodlands.farm,78CA398EBABD,,1961827241,0,,,
11,12/03/13,13:22:08,Renew,192.168.1.101,Mattys-iphone.woodlands.farm,78CA398EBABD,,1961827241,0,,,
11,12/03/13,13:22:11,Renew,192.168.1.101,Mattys-iphone.woodlands.farm,78CA398EBABD,,1961827241,0,,,
11,12/03/13,13:26:28,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,560813771,0,,,
11,12/03/13,13:26:30,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,560813771,0,,,
11,12/03/13,13:27:02,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,528184842,0,,,
11,12/03/13,13:27:05,Renew,192.168.1.116,android-5034be9390f051be.woodlands.farm,6CB7F460237C,,528184842,0,,,
11,12/03/13,13:27:31,Renew,192.168.1.117,Bobette.woodlands.farm,30F7C58ADD71,,1148184775,0,,,
11,12/03/13,13:27:33,Renew,192.168.1.117,Bobette.woodlands.farm,30F7C58ADD71,,1148184775,0,,,
12,12/03/13,13:32:34,Release,192.168.1.106,,888717A9F08A,,3870922839,0,,,
10,12/03/13,13:32:38,Assign,192.168.1.106,,888717A9F08A,,3870932902,0,,,
24,12/03/13,13:41:46,Database Cleanup Begin,,,,,0,6,,,
25,12/03/13,13:41:46,0 leases expired and 0 leases deleted,,,,,0,6,,,
25,12/03/13,13:41:46,0 leases expired and 0 leases deleted,,,,,0,6,,,
12,12/03/13,13:42:39,Release,192.168.1.106,,888717A9F08A,,3870932902,0,,,
10,12/03/13,13:42:41,Assign,192.168.1.106,,888717A9F08A,,3870964754,0,,,
11,12/03/13,14:05:48,Renew,192.168.1.117,Bobette.woodlands.farm,30F7C58ADD71,,1181739207,0,,,
11,12/03/13,14:05:50,Renew,192.168.1.117,Bobette.woodlands.farm,30F7C58ADD71,,1181739207,0,,,
11,12/03/13,14:05:52,Renew,192.168.1.117,Bobette.woodlands.farm,30F7C58ADD71,,1181739207,0,,,
11,12/03/13,14:28:35,Renew,192.168.1.117,Bobette.woodlands.farm,30F7C58ADD71,,1215293639,0,,,
11,12/03/13,14:38:01,Renew,192.168.1.105,,183F47B7B176,,1909203724,0,,,