On Tue, Jan 6, 2009 at 3:11 PM, Stuart Henderson <s...@spacehopper.org> wrote: > Release is an optional part of DHCP but some servers won't reassign the > IP address to a client with another MAC unless it happens. In that case > the best option is probably to try another DHCP client from ports/packages. > > At least in the current OpenBSD version you have a couple of options; > the ISC client allows this with the -r flag, and the WIDE client allows > it with SIGUSR2.
It's good to know that the isc-dhcp-client from ports lets you do this; it would be nice if the dhclient in base had this functionality. If it's a matter of "we don't have time -- submit a patch", I'd be happy to port that functionality (disclaimer: assuming the code isn't extremely hairy; I haven't delved into it yet), but I don't want to waste my time if it's not likely to be accepted. My reason for needing this is that my ISP (actually, I know of several like this) is like the server you describe, in that it refuses to hand out another DHCP lease if I have an active lease for a different MAC address. After releasing that lease, I can then obtain a new one. This is most likely to happen if I swap out the box acting as my firewall/router, swap ethernet cards (or which ethernet card my DSL modem is connected to), or switch between using an OpenBSD box and a hardware router, etc. Without the DHCPRELEASE functionality, the only option is to wait until the old lease expires. Luckily my current ISP gives leases of 1 hour (maybe 2, don't remember for sure) rather than a full day. And granted, I don't do this very often, as once my firewall is set up I tend to leave it alone (aside from applying errata) but during initial setup, and/or when trying to debug why my net connection isn't working right, it does come in handy. Andrew
