sendmail && dhcp

[Lowell Gilbert]

Matthias Apitz <guru at unixarea.de> writes:

> El día Thursday, February 26, 2015 a las 10:50:50AM -0500, Lowell Gilbert escribió:
>
>> Matthias Apitz <guru at unixarea.de> writes:
>> 
>> > What would be the best way to restart (or defer the start of sendmail)
>> > until the correct DNS is in place? For the tun interface I'm using a
>> > devd(8) hook, but I'm looking more for a general solution.
>> 
>> dhclient-script(8) is one way.
>
> Thanks for the hint. I've played around with the hooks script
> /etc/dhclient-exit-hooks; but this is not invoked when PPP brings up the
> interface tun(4), routing etc. because this is not done by dhclient(8),
> but directly by the pppd(8) and its hooks.

Unless you're running DHCP over the PPP link, which isn't quite as silly
as it sounds.

Another option would be to run your own resolver daemon on the
machine. That moves your configuration problem from sendmail to the
resolver (unless you go straight to the root for your lookups), but at
least it moves the DNS problem to DNS.

Are you sure you *need* sendmail running by default? Most laptops don't.