Bad_address in DHCP with iPads

[ass17]

Has any one experienced the DHCP server displaying BAD_ADDRESS for all apple devices.

 

No matter how many times we delete them, they come back within seconds.

 

Our DHCP is on 2003 server

[ass17]

None of our wireless devices will connect above a certain address, it seems as if something is trying to exhaust all the remaining available addresses.

 

Please help.

[Roberto]

I think my first question would be: is this only affecting apple devices or are you only trying to get apple devices to work at the moment so that's the only thing you're seeing the error with? What happens if you connect a random Windows or Linux laptop to the network right now that's not been on there before?

 

If "something" is trying to exhaust all the valid addresses then presumably your DHCP server is showing a lot of leases. Are the leases valid? E.G. do they point to mac addresses of devices that actually exist on your network?

 

Has it *ever* worked?

[ass17]

It started with any devices apple and windows.

[ass17]

The MAC address are silly small string ones that mean nothing.

 

DHCP is working for all other devices on the the network. Even wireless ones up to ip 106 anything above it up to 254 returns bad address.

[Roberto]

Those silly strings might not be quite so silly - they may be inverted IP addresses in hex.

 

e.g. 010fa8c0 -> 01 0f a8 c0 (hex) -> 01 15 168 192 (decimal) -> 192.168.15.01 (ip address).

 

If it's confined to a narrow range, my first thought would be an overlapping/rogue DHCP server that's issuing those addresses (fundamentally, BAD_ADDRESS is reporting an IP address conflict). As you mention iPads, it might not be that simple.

 

There's an article here from 2011 detailing an issue with iPads and DHCP which could produce the issue you're seeing but you'd like to think apple would have fixed that by now.

 

It might be worth dropping your lease time then doing an ipconfig /release and an ipconfig /renew on all your systems, but I appreciate that's not a trivial exercise.

Edited April 10, 2013 by Roberto

[Michael]

BAD_ADDRESS appears when you have 2 DHCP Servers or more with conflict detection enabled. You'd normally set conflict detection to 1, 2 or 3 as to the number of attempts DHCP should make.

 

If you had a rogue DHCP Server, the odds are it'll be in a different IP range or class. For example you may have a class A range at school and a class C range at home which is pretty normal.

[Roberto]

BAD_ADDRESS appears when you have 2 DHCP Servers or more with conflict detection enabled. You'd normally set conflict detection to 1, 2 or 3 as to the number of attempts DHCP should make.

 

This was my first thought but as the OP would presumably know if they had more than one DHCP server on the network, we're both right to check but I suspect something more subtle is going on. (And if it was a rogue server issuing addresses from a different range then this would be obvious as some clients would start getting incorrect addresses)

 

For example you may have a class A range at school and a class C range at home which is pretty normal.

 

Classful networking hasn't been in use since about the mid-1990s. I'd say it was dangerous to make assumptions on how a network is laid out based on it.

Edited April 10, 2013 by Roberto

[Michael]

Classful networking hasn't been in use since about the mid-1990s. I'd say it was dangerous to make assumptions on how a network is laid out based on it.

 

I don't quite follow. An IP starting with 10 and another starting with 192 for example are in different classes. 256 IPs available in a class C and over 16 million available in a class A.

[Roberto]

I don't quite follow. An IP starting with 10 and another starting with 192 for example are in different classes. 256 IPs available in a class C and over 16 million available in a class A.

 

Classes don't mean anything any more. They haven't been in use since 1993 or so. You can't make assumptions about the subnet allocated to an IP address based on the address "class". I really don't know how else to put it.

[ass17]

Classless was replaced by CIDR

[ass17]

Sorry, classful not classless

[ass17]

We defo don't have a second DHCP as our network is 172 and other DHCP servers can't return bad addresses if they are configured to a different network address like 192

[ass17]

Our wireless leases are set to 8 hours

[ass17]

Worse thing is that I change the range from 172.31.1.1 -172.31.1.254 to 172.31.1.1 -172.31.1.150 and none of the wireless devices that previous. Connected at 151 or above would retry any addresses lower.