network interface monitoring?

[Yousif Hassan]

> the rc.conf manpage has a few options regarding the function of dhcp including:
> 
>      synchronous_dhclient
>                  (is currently in beta test.  Set to ``bool'') to start
>                  dhclient(8) only in response to interface events and not syn-
>                  chronously at startup.  This behavior can be overridden on a
>                  per-interface basis by replacing the ``DHCP'' keyword in the
>                  ifconfig_<interface> variable with ``SYNCDHCP'' or
>                  ``NOSYNCDHCP''.
> 
> and
> 
>      background_dhclient
>                  (bool) Set to ``YES'' to start the DHCP client in background.
>                  This can cause trouble with applications depending on a work-
>                  ing network, but it will provide a faster startup in many
>                  cases.

What a great list.  Very useful suggestions, thanks!  The behavior you
get from setting synchronous_dhclient="NO" is exactly what I was looking
for.