Re: networking

[Tom H <tomh0665@gmail.com>]

On Sun, Jan 16, 2011 at 10:19 AM, Osamu Aoki <osamu@debian.org> wrote:
> On Fri, Jan 14, 2011 at 08:13:38PM +0530, Mihira Fernando wrote:
>>
>> AFAIK, allow-hotplug makes the interface come up only when a cable
>> is plugged in.
>
> It seems Bob explained good basics but I think there is some other
> confusion here.
>
> No when device becomes available to Linux kernel even if wires are not
> plugged.  The wiring event is something you need ifplugd to take care.
>
>> auto makes the interface come up at boot time
>> regardless of the cable state.
>
> http://www.debian.org/doc/manuals/debian-reference/ch05.en.html#list-of-stanzas-in-eni
> (I read the source to come up with this table).
>
> auto is old name for allow-auto which starts itself by the initialization script.
>
> allow-hotplug is new and it starts when the device becomes available to
> Linux kernel.

Thanks for the allow-hotplug/ifplugd clarification.

Interfaces tagged with "allow-hotplug" in "/etc/network/interfaces"
are brought up by "/lib/udev/net.agent" because it runs "ifup
--allow=hotplug".

Interfaces tagged with "auto"/"allow-auto" in
"/etc/network/interfaces" are brought up by "/etc/init.d/networking"
because it runs "ifup -a".