DHCP Failover - initial Configuration

Simon Hobson dhcp1 at thehobsons.co.uk
Thu Aug 9 16:32:03 UTC 2018

perl-list <perl-list at network1.net> wrote:

>> Yes I already ran into the "issue" that the client can request a lease for a
>> certain time. Thats why we have
>> min-lease-time 3600;
>> default-lease-time 3600;
>> max-lease-time 3600;
>> set in our dhcpd.conf

> Even that doesn't guarantee anything.  Clients can and do still suggest and receive a different lease length.  Its really not often, but I have seen it.  For example, some versions of windows will initially request an hour lease followed by a full lease length (ie: what you have configured in your directives) at renewal time.  This would be when you have longer than an hour lease lengths configured.

The server should never offer a lease shorter than min-lease-time, or longer than max-lease-time - except when failover is/has happened and MCLT is in effect. A client could choose to not use the full lease length, but it cannot (unless broken) use the address for longer than the lease time offered.

More information about the dhcp-users mailing list