How to successfully restart a network without reboot over SSH?
In Ubuntu 14.04 neither sudo service networking restart nor sudo /etc/init.d/networking restart do anything any more. They also both exit with code 1. Something has obviously changed (or half changed) but I can't find what. This obviously causes problems with remote network reconfiguration and tools like Ansible.
$ sudo bash -x /usr/sbin/service networking restart
[sudo] password for wirehive:
++ basename /usr/sbin/service
+ VERSION='service ver. 0.91-ubuntu1'
++ basename /usr/sbin/service
+ USAGE='Usage: service < option > | --status-all | [ service_name [ command | --full-restart ] ]'
+ SERVICE=
+ ACTION=
+ SERVICEDIR=/etc/init.d
+ OPTIONS=
+ '[' 2 -eq 0 ']'
+ cd /
+ '[' 2 -gt 0 ']'
+ case "${1}" in
+ '[' -z '' -a 2 -eq 1 -a networking = --status-all ']'
+ '[' 2 -eq 2 -a restart = --full-restart ']'
+ '[' -z '' ']'
+ SERVICE=networking
+ shift
+ '[' 1 -gt 0 ']'
+ case "${1}" in
+ '[' -z networking -a 1 -eq 1 -a restart = --status-all ']'
+ '[' 1 -eq 2 -a '' = --full-restart ']'
+ '[' -z networking ']'
+ '[' -z '' ']'
+ ACTION=restart
+ shift
+ '[' 0 -gt 0 ']'
+ '[' -r /etc/init/networking.conf ']'
+ which initctl
+ grep -q upstart
+ initctl version
+ case "${ACTION}" in
+ stop networking
stop: Job failed while stopping
+ :
+ exec start networking
start: Job is already running: networking
What is the correct way to restart networking in Ubuntu 14.04 Server remotely?
Turns out this is a "feature". The only supported way of restarting an interface in Ubuntu Server is sudo ifdown eth0 && sudo ifup eth0
https://bugs.launchpad.net/ubuntu/+source/ifupdown/+bug/1301015
ifdown, ifup didn't work for me (likely SSH connection timeout before the second command). What did work was:
sudo service network-manager restart
This was on a 14.04 ubuntu-desktop system.
What's changed is they don't want you "bouncing" the network anymore. stopping, and starting, still work. restart no longer works. I just "solved" this "problem", that is to say I got the old behavior back. To revert to prior behavior: Take a 13.10 /etc/init/networking.conf file and replace the 14.04 file with it. (edit: clarified which replaces which)
The process looks like this:
(Just before this, I configured my /etc/network/interfaces for eth1 on a 192.168.117.x address)
"/etc/network/interfaces" 16L, 413C written
root@1404-Anode:~# service networking restart
stop: Job failed while stopping
start: Job is already running: networking
root@1404-Anode:~# echo "hmm, wth?"
hmm, wth?
root@1404-Anode:~# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0c:29:d6:a8:19
inet addr:192.168.115.105 Bcast:192.168.115.255 Mask:255.255.255.0
inet6 addr: 2002:4077:9050:1234:a08c:29c1:ce9b:a57b/64 Scope:Global
inet6 addr: fe80::20c:29ff:fed6:a819/64 Scope:Link
inet6 addr: 2002:4077:9050:1234:20c:29ff:fed6:a819/64 Scope:Global
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:646 errors:0 dropped:0 overruns:0 frame:0
TX packets:531 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:58748 (58.7 KB) TX bytes:75465 (75.4 KB)
(lo removed here)
root@1404-Anode:~# cd /etc/init
root@1404-Anode:/etc/init# diff networking.conf.1310 networking.conf.1404
13c13
< and (stopped udevtrigger or container)) or runlevel [2345]
---
> and (stopped udevtrigger or container)) or runlevel [2345] or stopped networking >RESULT=failed PROCESS=post-stop EXIT_STATUS=100
16a17,20
> if [ "$UPSTART_EVENTS" = "stopped" ] && [ "$UPSTART_JOB" = "networking" ] && [ "$EXIT_STATUS" = "100" ]; then
> exit 0
> fi
>
21a26,31
> if [ -z "$UPSTART_STOP_EVENTS" ]; then
> echo "Stopping or restarting the networking job is not supported."
> echo "Use ifdown & ifup to reconfigure desired interface."
> exit 100
> fi
root@1404-Anode:/etc/init#
Do the same for /etc/init.d/networking script, which is what the /etc/init/networking.conf file references/calls.
root@1404-Anode:/etc/init# cp networking.conf.1310 networking.conf
root@1404-Anode:/etc/init# cd ../init.d
root@1404-Anode:/etc/init.d# diff networking.1404 networking.1310
15d14
< STATEDIR="$RUN_DIR/state"
21a21,27
> # Make sure that it's clear to the user that they shouldn't use this
> # script under upstart
> if init_is_upstart; then
> echo "ERROR: Calling a sysvinit script on a system using upstart isn't supported. Please use the 'service' command instead."
> exit 1
> fi
>
52,54d57
< if ! chown root:netdev "$RUN_DIR" ; then
< log_warning_msg "can't chown $RUN_DIR"
< fi
160,162d162
< if init_is_upstart; then
< exit 1
< fi
166c166
< state=$(ifquery --state)
---
> state=$(cat /run/network/ifstate)
root@1404-Anode:/etc/init.d# cp networking.1310 networking
root@1404-Anode:/etc/init.d# service networking restart
networking stop/waiting
networking start/running
root@1404-Anode:/etc/init.d# ifconfig
eth0 Link encap:Ethernet HWaddr 00:0c:29:d6:a8:19
inet addr:192.168.115.105 Bcast:192.168.115.255 Mask:255.255.255.0
inet6 addr: 2002:4077:9050:1234:a08c:29c1:ce9b:a57b/64 Scope:Global
inet6 addr: fe80::20c:29ff:fed6:a819/64 Scope:Link
inet6 addr: 2002:4077:9050:1234:20c:29ff:fed6:a819/64 Scope:Global
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:3398 errors:0 dropped:0 overruns:0 frame:0
TX packets:2545 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:318654 (318.6 KB) TX bytes:418804 (418.8 KB)
eth1 Link encap:Ethernet HWaddr 00:0c:29:d6:a8:23
inet addr:192.168.117.105 Bcast:192.168.117.255 Mask:255.255.255.0
inet6 addr: fe80::20c:29ff:fed6:a823/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:98 errors:0 dropped:58 overruns:0 frame:0
TX packets:15 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:20055 (20.0 KB) TX bytes:1226 (1.2 KB)
(lo removed)
root@1404-Anode:/etc/init.d# echo "hah, it works! *8^)"
Hah, it works! *8^)
root@1404-Anode:/etc/init.d#
(note: the steps where I scp'd the 1310 versions into the 1404 system are omitted for brevity).
Obviously there's a reason they put a defensive exit in there, but they don't bother to really output what's going on very well.
An entry does go into /var/log/upstart/networking.log when you try, that looks like:
Stopping or restarting the networking job is not supported.
Use ifdown & ifup to reconfigure desired interface.
But they really could/should have output that as the dialog message when you try service networking restart. ah well. figured it out and even a old-way work around.
EDIT: I have found this causes an unintentional triggering of the script controlled by /etc/init/failsafe.conf which is undesirable as it causes a 120 second timeout delay in every boot up... as well as perhaps masking actual misconfigurations/network issues which this delay's appearance would indicate, but it's already showing all the time. (e.g. An unplugged cable, which was allowing access to a network file share mapped in /etc/fstab, for instance)
In any case, I will figure out what is causing this always hitting the timeout, and post a fix when I find it.
In reference to kvm-user420's response, I've gone ahead and setup a script to replace Ubuntu 14.04's networking scripts with that of Ubuntu 13.10
You can find it here: https://github.com/metral/restore_networking
Enjoy!