Creation of duplicate leases in failover mode

David W. Hankins David_Hankins at
Tue Mar 14 15:37:53 UTC 2006

On Tue, Mar 14, 2006 at 12:33:39PM +0100, Patrick Schoo wrote:
> The primary should just hand out the lease it has found, or should load 
> balance to the secondary. This behaviour could be based on the value of the 
> split variable.

That's an interesting interpretation.  It's definitely an option I
haven't considered.

I have code queued for feature release which implements what I will
term 'MAC address affinity'.  I'm fairly certain this is going into

In short, when leases go to FREE state, it checks the LBA to see
which peer is likely to reallocate it, and goes ahead and reassigns
it into that state (IFF BACKUP, if it wants to be FREE, it already
is).  Pool balance checks do two loops over the pool as well - the
first following mac address affinity, only moving leases the peer
would prefer to own, the second to enforce pool balance.

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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