option 51 ' dhcp-lease-time' vs other lease time statements
David W. Hankins
David_Hankins at isc.org
Tue Sep 19 16:49:03 UTC 2006
On Tue, Sep 19, 2006 at 10:46:41AM -0400, Aaron Bennett wrote:
> What's the difference? What exactly does option 51 do and how does that
> compare to the other ways to specify a lease time? What I'm looking for
> is the migrate the exact _intent_ of the Win2K configuration
> intelligently into isc-world.
In dhcpd.conf, 'option dhcp-lease-time foo;' will be over-ridden by
a value selected by the server. So it will have no effect except to
cause a logline warning about the over-ride.
If the client supplies option 51, the server selects a value close to
the client-supplied value that falls between the min- and max-lease-time
If the client does not supply option 51, the server does the same thing
except uses the default-lease-time (so it's a good idea to choose a
default that is somewhere inside your min/max range).
If you're using failover, a second layer of complexity is added.
> ( I'll contribute the script back to isc when it's done -- finished
> product will handle both config & lease database )
dhcp-suggest at isc.org please.
ISC Training! October 16-20, 2006, in the San Francisco Bay Area,
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David W. Hankins "If you don't do it right the first time,
Software Engineer you'll just have to do it again."
Internet Systems Consortium, Inc. -- Jack T. Hankins
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