static IP allocations in dynamic ranges -why not?

Foggi, Nicola NFOGGI at
Mon Jun 7 14:27:51 UTC 2010

Something like this will set the reserved flag via omshell:

port 7911
key xxxx xxxx
new lease
set ip-address=$IP
set flags=04:00:00:00

you do need to set it on both servers if you're running failover between them.  You cannot unset it reserved from what i've found.  The funkiness I've seen that ISN'T patched yet:

1. Lease prioritization in a 2 server pair environment the lease prioritization that classifies the "reserved" lease as preferred over a new lease is not always accurate, so doing a dhcp discover may result in a different ip being assigned.  We've seen it pretty heavily, a patch that seems to work for me is posted here:

the response was that should never be executed as it overlaps, but without it i have problems, i haven't had time to go track down if there is a bug somewhere else.

2. If the lease is not in an ACTIVE state when you set it to RESERVED the server will error out and shut down with an error message something like lease state transition invalid.  You can then go manually edit the lease file and fix the lease.  Again, only saw this on our failover pair of dhcp servers, not on a stand alone, but this was harder to duplicate, so i may of not done it right on the stand alone.

This one is pretty annoying when it happens... probably an easy way to fix it, but haven't had time...

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