Re: in /etc/network/interfaces: "auto" vs "allow-hotplug"

[Henrique de Moraes Holschuh <hmh@debian.org>]

On Sat, 23 Sep 2017, Rick Thomas wrote:
> I have two machines (out of a group of ten) that will not bring up
> their ethernet interface at boot time if the interfaces is of type
> “allow-hotplug”.  When I change that to “auto” the interface comes up
> at boot with no problem…

...

> Anybody have a clue as to what’s going on?

auto:            try to ip link set <dev> up  at boot.  Best choice for
                 anything PCIe/SoC.

allow-hotplug:   *wait* for kernel+drivers+udev to detect the device,
                 then ip link set <dev> up it.  The only thing that can
                 deal with annoying USB, SDIO, etc.

This can be kinda important when non-auto-loading stuff is involved, or
when network file systems are involved.

So, look at what *exact* kind of network device you're dealing with.

-- 
  Henrique Holschuh