DHCPd sending lease expiration of 3600 seconds

Simon Hobson dhcp1 at thehobsons.co.uk
Wed Feb 18 19:17:03 UTC 2009

Jeff Haran wrote:

>WRT 32 bit rollovers, I haven't read where the protocol defines the
>beginning and end of time to correspond to the Unix Epoch. The RFC says:
>9.2. IP Address Lease Time
>    This option is used in a client request (DHCPDISCOVER or DHCPREQUEST)
>    to allow the client to request a lease time for the IP address.  In a
>    server reply (DHCPOFFER), a DHCP server uses this option to specify
>    the lease time it is willing to offer.
>    The time is in units of seconds, and is specified as a 32-bit
>    unsigned integer.
>If somebody wants to assign 136 year leases, why should the
>implementation prohibit that?

Well I guess it's just an oversight. Perhaps most of the people 
involved in the RFC just naturally worked on the basis of Unix time. 
I doubt there was any intention to artificially limit leases, but 
back when this was defined, 2038 was a LONG way off !

Simon Hobson

Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed
author Gladys Hobson. Novels - poetry - short stories - ideal as
Christmas stocking fillers. Some available as e-books.

More information about the dhcp-users mailing list