According to Princeton University, the iPad (and perhaps other iOS devices?) seems to have had various issues with DHCP that exist even on the current version (4.3.3). The current one involves the device keeping (and using) an expired DHCP lease under certain circumstances.
- iPhone OS 3.2 on iPad Stops Renewing DHCP Lease, Keeps Using IP Address
- iOS 3.2.1 - 4.0.2 Requests a DHCP Lease Too Often
- iOS 4.1 - 4.3.3 Allows DHCP Lease to Expire, Keeps Using IP Address
It looks like Princeton's course of action is to let the user know of the workaround they've devised and ban them from the network if the issue still persists. Their article also mentions:
Sites that do monitor for these problems closely are unlikely to encounter the issue if they assign DHCP leases with expiration times longer than about an hour.
I saw one article (having trouble finding it now) that mentioned configuring your DHCP server to ping addresses (to ensure no client is claiming it) before offering them to clients.
That said, these issues have supposedly existed for over a year now and I don't see much discussion (on here or Google) about dealing with it on a medium/large scale network.
- Have you experienced any issues related to this on your network?
- If so, how have you dealt with them?