Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Question: I've some Debian or Ubuntu based servers here with

allow-hotplug eth0

and some with

auto eth0

in /etc/network/interfaces. What is the difference between them? If I'm correct, both are bringing up the interfaces during startup and if a cobel is pluged in. Right?


share|improve this question
up vote 3 down vote accepted

allow-hotplug allows you to plug in a new network device (say, turning on a network card, PCMCIA cards, etc.).

auto is just auto-detection of the port being plugged in IIRC to bring the interface online.

share|improve this answer

One potential serious consequence of allow-hotplug instead of auto is that allow-hotplug interface usually do not come up after issuing a

/etc/init.d/network restart

they go down but don't come up again which leaves you with a "down" interface.

share|improve this answer
Thanks, good to know – Thomas Deutsch Nov 10 '11 at 8:52

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.