On Mon, Oct 20, 2008 at 07:00:38PM +0800, Jack wrote: > >If that wasn't done would there be any need for this special knowlege > >of iSCSI (and NFS) both of which seem very "icky" but if needs must. > I think NO, no special knowledge needed if the configuration of the if > doesn't change at all during shutdown. > > What breaks if dhcpagent does not reset back to 0.0.0.0 on shutdown > >? Could it still send the DHCP release to the DHCP server but not > >reset the interface ? > It is a solution, but violating the protocol more severely.
Well, yes, but the real issue is that the lease should not be released until after kernel networking modules, like the iSCSI initiator and NFS client, have stopped all activity. Here we have a chicken-and-egg problem. The obvious solution is to move DHCP releasing into the kernel and have a way for the iSCSI initiator and NFS client to get holds on interfaces such that they will not release their leases until the holds are released. So when dhcpagent gets SIGTERM it should put the interface into "release DHCP lease and canonize as soon as all holds go" mode. Would that be ETOOHARD? Nico --
