ipv6: T1, T2, default-lease-time and preferred-lifetime

[Maurice Massar]

hi,

On Thu, Feb 11, 2010 at 11:32:51AM +0100, "Lorenz Röhrl" wrote:
> Hi!
> 
> There are two dhcp-timers, T1(renew) and T2(rebind). Additionally there
> is a valid and preferred lifetime which are assigned to ipv6-addresses.
[...]
> I did search for T1, T2, renew and rebind in the man page, but i couldn't find anything useful.

I searched too, and found it. Not in the manpage, but in the
example-config and in the sources:

doc/examples/dhcpd-dhcpv6.conf:
======================================
# T1, the delay before Renew
#  (default is 1/2 preferred lifetime)
#  (set to 1 hour)
option dhcp-renewal-time 3600;

# T2, the delay before Rebind (if Renews failed)
#  (default is 3/4 preferred lifetime)
#  (set to 2 hours)
option dhcp-rebinding-time 7200;
======================================

server/dhcpv6.c:
======================================
        /*
         * T1/T2 time selection is kind of weird.  We actually use DHCP
         * (v4) scoped options as handy existing places where these might
         * be configured by an administrator.  A value of zero tells the
         * client it may choose its own renewal time.
         */
======================================

The part "A value of zero tells the client it may choose its own renewal
time." actually triggerd a Bug in the DHCPv6-Client in a IBM 3584 Tape
Library Managment Interface. It choosed to interpret it as 0 seconds,
and start renewing in a loop...

cu
Maurice