Maximum possible value for *-lease-time?

David W. Hankins David_Hankins at
Fri Jan 11 15:51:26 UTC 2008

On Fri, Jan 11, 2008 at 11:20:42PM +1100, Glenn Satchell wrote:
> It's a 32 bit number, so the maximum value is 2^32 - 1, but with an

Note however that 2^32-1 is a special value in DHCP that means

> absolute limit of that time in 2038 when the number of seconds since
> the epoch reaches 2^32. So, it can be a really dig number, bigger than
> you're likely to ever need.

The DHCP protocol wire transfers relative timestamps, not absolute
timestamps, because it's too hard to synchronize clocks.  So 2038 only
comes into play if the system(s) scheduling timeouts (on either side
of the DHCP protocol) have a 32-bit time_t.

Ostensibly, between now and 2038 your OS will upgrade past that.

Ash bugud-gul durbatuluk agh burzum-ishi krimpatul.
Why settle for the lesser evil?
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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