Does the network need to be restarted after editing /etc/network/interfaces?

Question

On Debian - Say I have a network card eth0 on my /etc/network/interfaces file, and I want to add a new interface to it (that uses dhcp). Is it necessary to restart the networking service (/usr/sbin/service networking) when I do this in order to bring the new interface online? Or is there anything else I have to do after I edit the file?

I know that editing, say, dhcpd.conf requires dhcp to be restarted. Wasn't sure about interfaces.

Thanks for your help, from a developer pretending to be a sysadmin for a day.

score 6 · Accepted Answer · answered Apr 23 '12 at 21:33

6

You can either restart the nework service or just bring the new/modified interface down and up with a command like: (Note be sure to do this from the console or an out of band management interface)

ifdown ethX (Where X is the ID of your enternet interface) ifup ethX

answered Apr 23 '12 at 21:33

ckliborn

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does bringing the interface down and up bring the other machines on the interface offline temporarily? – smcg Apr 24 '12 at 13:35
yes - all addresses on that interface would be effected – ckliborn Apr 24 '12 at 17:26

score 1 · Answer 2 · answered Apr 23 '12 at 21:34

If you use NetworkManager, then you should not edit /etc/network/interfaces file and the configurations are applied without restart of the "service". If you edit it by hand, then you need to restart the networking configuration for the interface you are changing the config.

And I think that DHCP is not working for alias interfaces (this would be a limitation of the DHCP client).

Does the network need to be restarted after editing /etc/network/interfaces?

2 Answers2