Theoretical Max Lease Time

HAWKER, Dan dan.hawker at
Thu Aug 31 13:59:00 UTC 2006

> >What is the theoretical maximum lease time that you can set 
> in DHCPD???
> About 30 years I think, as in end time must be less than "now + 
> 2^31-1 seconds" and also less than the end of time as the system 
> knows it (2^31-1 seconds after midnight 1st Jan 1970) which IIRC is 
> sometime in 2036.

Ah, that should be sufficient :)

> Bear in mind that should they change their client ID then they will 
> still get a different address, and in the absence of a client id then 
> the address will change with any change of virtual MAC address (are 
> they random or static MAC addresses ?).

Yeah, that I know. Its just the initial config of a new VM that causes
headaches. Vmware dynamically creates the MAC address initially (so is
random, well ish) and then reuses that MAC address as long as the config
file and the *real* MAC address don't change (as I understand it). Hence, if
the VM instance is moved around or the config files name is changed, yeah
it'll change too, but if it stays put it'll be OK.

Am just trying to make the initial rollout as automatic and seamless as
possible, yet allow the VMs to have pseudo-static IPs without knowing the
MAC address(es).

Thanks for the info


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