preventing dhclient from running under certain conditions

[shimi]

On Wed, Oct 29, 2014 at 2:06 PM, Oleg Goldshmidt <pub at goldshmidt.org> wrote:
> [*] Without discussing the actual requirements, consider a trivial
> example. Suppose you have several DHCP VLANs configured on eth1, and suppose
> that for various operational reasons the eth1 link may occasionally be down.
> What happens in such a case is that dhclient keeps trying, for all VLANs and
> for a long time, before giving up. You don't want this to keep a machine
> from booting, to keep other interfaces from starting, etc. One would want to
> detect this early (e.g., using ethtool or similar) and not even attempt to
> bring up DHCP interfaces. [In my mind, this is a bug in dhclient, but this
> is beside the point...]
>

What about allow-hotplug?
http://www.debian.org/doc/manuals/debian-reference/ch05.en.html#_the_basic_syntax_of_etc_network_interfaces

-- Shimi