Re: [dhcwg] Query Regarding DHCP Lease time, Rebind Time and Renewal Time.

"David W. Hankins" <David_Hankins@isc.org> Tue, 26 October 2010 22:35 UTC

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From: "David W. Hankins" <David_Hankins@isc.org>
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Subject: Re: [dhcwg] Query Regarding DHCP Lease time, Rebind Time and Renewal Time.
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On Fri, Oct 22, 2010 at 11:50:57AM +0530, Ramesh Ganapathi wrote:
> 1)     What should be the expected behavior if the DHCP client receiver a
> OFFER with lease time of 0(zero).?

If it is a DHCPOFFER, the client hopefully would not select it in
SELECTING state, and would instead select a valid lease from a not
broken DHCPv4 server colocated on the network.

Realistically, DHCPv4 clients do not have very good selection
algorithms.

> 2)    If the DHCP Client receives DHCP OFFER with lease timer of 2 seconds
> the T1(Rebind Timer) and T2 (Renew Timer) timer value will be round of to 1
> second.
> 
> What should be expected behavior if the T1 and T2 timer value are same?

This is a trick question.  In the case of a DHCPOFFER with a valid
lease time, the client continues to SELECTING state.

-- 
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