dhclient: Using dhcp-lease-time in expressions

Jordan Russell jr-list-2011 at quo.to
Sun Dec 18 07:43:07 UTC 2011

On 12/16/2011 12:40 AM, Glenn Satchell wrote:
> You're stuck in a chicken and egg situation here. When you send out the
> initial DHCPDISCOVER, there is no lease-time assigned yet, so the value is
> undefined and causes the expression to fail.

FWIW, I have an active lease, so I'm seeing a broadcast DHCPREQUEST
followed by a DHCPACK.

The "leased_lease: not available" message is actually logged *after* the
DHCPACK message. So it seems that dhclient ought to already have the
server options in hand at the time the expression is evaluated/failing.

I wonder if this "leased_lease" construct simply does not exist until
the lease is finalized, making lease-time unusable from any expression
evaluated at DHCPACK time?

> Looking at the dhcp-eval man page you could wrap this with "if exists".
> Although that says it wants an option it may also work with lease-time.

Will give that a shot, and see if log() yields any clues...

Jordan Russell

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