Arch Linux run script a minute after boot

Question

I have set up a bridge between eth0 and wlan0 with netctl. It works fine if I tell it to configure eth0 and wlan0 at startup and then for me to manually start the bridge after it boots. If I tell the bridge to start automatically as well though for some reason the wlan adapter does not connect to an access point. I therefore need "netctl start bridge" to run a minute or so after the entire system has finished booting. Any idea how I should do this?

PS. This is a headless system as in no xorg so running it at xorg startup won't work.

score 19 · Answer 1 · edited May 19 '18 at 13:47

19

You can use systemd timers to execute script a minute after boot.

First, create service file (/etc/systemd/system/myscript.service):

[Unit]
Description=MyScript

[Service]
Type=simple
ExecStart=/usr/local/bin/myscript

Then create timer (/etc/systemd/system/myscript.timer):

[Unit]
Description=Runs myscript one minute after boot

[Timer]
# Time to wait after booting before activation
OnBootSec=1min
Unit=myscript.service

[Install]
WantedBy=multi-user.target

Now enable and run it:

# systemctl enable myscript.timer
# systemctl start myscript.timer

edited May 19 '18 at 13:47

Boris

103
4

answered Jun 20 '14 at 16:46

anlar

4,096
3
30
54

Couldn't you add an after line so the script runs after wlan0 is configured? – StrongBad Jun 20 '14 at 19:12
@StrongBad, probably you can add `Requires=sys-subsystem-net-devices-wlan0.device` and `After=sys-subsystem-net-devices-wlan0.device` to service to ensure that it will start after wlan0 configuration. But I haven't tested it by myself. – anlar Jun 20 '14 at 19:27

Livinglifeback · Accepted Answer · 2014-06-20T14:47:06.093

4

Arch uses systemd to manage startup processes (daemons and the like as well).

You can write a script that simply executes the command that you want, or sleep for a min and then execute. Then add it to the boot process with the instructions on the

wiki

if you add a sleep:

#!/bin/sh
sleep 60 # one min
netctl start bridge

It should work perfectly fine. Systemd should spawn another process when it executes your script so it shouldn't make your system hang.

edited Jun 20 '14 at 14:47

answered Jun 20 '14 at 14:09

Livinglifeback

1,586
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Well that's obvious but I have no idea how to make it start at the right time – Gerharddc Jun 20 '14 at 14:12
add a sleep to is #!/bin/sh sleep(60) # one min netctl start bridge It shouldn't cause the system to hang as it should be spawned as a separate process. – Livinglifeback Jun 20 '14 at 14:14
Could you please just give me an example file for this as I'm a bit to unexperienced to know how to implement that. – Gerharddc Jun 20 '14 at 14:17
Ok I've managed to get the file written and am now testing it – Gerharddc Jun 20 '14 at 14:32
Well this definitely works for getting it to run at the right time but strangely this still does not solve the problem that I am trying to solve with it – Gerharddc Jun 20 '14 at 14:38
What problem are you trying to solve? – Livinglifeback Jun 20 '14 at 14:38
The problem with the automatic bridge messing up my wlan connection – Gerharddc Jun 20 '14 at 14:42
What do you use to connect your wlan? wicd, networking manager etc? – Livinglifeback Jun 20 '14 at 14:43
I use netctl but luckily it seems it just starting working after I increased the delay some more – Gerharddc Jun 20 '14 at 14:44
Glad it worked for you. – Livinglifeback Jun 20 '14 at 14:45
1

The parens in "sleep(60)" are not necessary or syntactically valid for shell scripts. – godlygeek Jun 20 '14 at 14:46
3

`sleep` in a `systemd` startup script is contrary to the purpose of having a `systemd` startup script. – mikeserv Jun 20 '14 at 17:08

score 1 · Answer 3 · answered Oct 20 '15 at 15:01

1

If you want something simple that's non-blocking, add the following to /etc/rc.local:

( sleep 60 && /path/to/command_or_script [opts] ) &

answered Oct 20 '15 at 15:01

Kevin Traas

111
1

Arch Linux run script a minute after boot

3 Answers3