DHCP for multiple networks with static and dynamic assignments

David W. Hankins David_Hankins at isc.org
Fri Mar 2 22:35:06 UTC 2007

On Fri, Mar 02, 2007 at 11:14:19PM +0100, Wojciech 'Wheart' Penar wrote:
>        allow unknown clients;

Ah ha.

"allow unknown[- ]clients;" implicitly denies known clients.

If a pool has an allow list, then the client must match the
any entry on the list or else it's denied.

If it has a deny list, the client must not match any entry on
the list or else it's allowed.

> host kangoo     {
>    hardware ethernet 00:14:22:E0:CE:3F;
>    fixed-address kangoo;
> }

Once a client has 1 matching host record, it becomes known,
even if that host record is not used for its configuration in
that round because the address is on the wrong network...

So since the dynamic pool only allows unknown clients...it can't

> I've just noticed, that in manual there is dash ("-") in the middle of
> "unknown-clients", but server doesn't complain about it and it is 
> working...

My memory is it's the same thing...I seem to recall that one of
these is the 'old syntax' that we didn't want to break when a
simpler syntax was determined to be the right one.

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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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