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

Ted Lemon <Ted.Lemon@nominum.com> Fri, 22 October 2010 21:13 UTC

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From: Ted Lemon <Ted.Lemon@nominum.com>
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Date: Fri, 22 Oct 2010 17:14:47 -0400
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To: Ramesh Ganapathi <rameshganapathi@gmail.com>
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Subject: Re: [dhcwg] Query Regarding DHCP Lease time, Rebind Time and Renewal Time.
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On Oct 22, 2010, at 2:43 PM, Ramesh Ganapathi wrote:
> T1 = (lease time * 0.5) = 2*0.5 = 1
> 
> T2 = (lease time * 0.875) = 2 * 0.875 = 1.75 (round of to 1)
> 
> What should be expected behavior if the T1 and T2 timer value are same?
> 
> Can some one please clarify.

You should expect that if you offer lease times that short, things will break, possibly in such a way as to take down your network with broadcast storms that will only stop when your DHCP server is shut down.   DHCP is not intended to offer leases that short.   As an example, I was recently staying at a motel where they offered two-minute leases.   *That* caused noticeable instability on my network because the VPN kept getting reset.   You really, really don't want to do this.

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