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.

Solution 1

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.

Solution 2

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

Solution 3

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

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

Comments

[Gerharddc]

Well that's obvious but I have no idea how to make it start at the right time

[Livinglifeback]

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.

[Gerharddc]

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]

Ok I've managed to get the file written and am now testing it

[Gerharddc]

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

[Livinglifeback]

What problem are you trying to solve?

[Gerharddc]

The problem with the automatic bridge messing up my wlan connection

[Livinglifeback]

What do you use to connect your wlan? wicd, networking manager etc?

[Gerharddc]

I use netctl but luckily it seems it just starting working after I increased the delay some more

[Livinglifeback]

Glad it worked for you.

[godlygeek]

The parens in "sleep(60)" are not necessary or syntactically valid for shell scripts.

[mikeserv]

sleep in a systemd startup script is contrary to the purpose of having a systemd startup script.

[StrongBad]

Couldn't you add an after line so the script runs after wlan0 is configured?

[anlar]

@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.