@reboot is not working in CRON

Issue

I’m trying to run a shell-script and a command at the start of my Ubuntu server.

Here is my CRON

@reboot /home/steam/check.sh
@reboot screen -d -S up -m node /var/www/html/Up1/server/server.js

What I’m getting in the logs:
grep CRON /var/log/syslog

Jul 19 19:48:28 vc1s cron[3185]: (CRON) INFO (pidfile fd = 3)
Jul 19 19:48:28 vc1s cron[3185]: (CRON) INFO (Running @reboot jobs)
Jul 19 19:48:28 vc1s CRON[3209]: (root) CMD (screen -d -S up -m node /var/www/html/Up1/server/server.js)
Jul 19 19:48:28 vc1s CRON[3211]: (root) CMD (/home/steam/check.sh)
Jul 19 19:51:20 vc1s cron[3779]: (CRON) DEATH (can't lock /var/run/crond.pid, otherpid may be 3185: Resource temporarily unavailable)
Jul 19 19:55:01 vc1s CRON[3996]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)

My check.sh.

#!/bin/bash

until screen -d -S unturned -m /home/steam/start.sh; do
        echo "Server 'myserver' crashed with exit code $?.  Respawning.." >&2
        sleep 1
done

My start.sh. It’s for launching an Unturned game server. I don’t think this script is important but I guess I should show you.

#!/bin/bash
# This script starts a Unturned 3 server on Linux machines
# Syntax: start.sh <instance name>
# Author: fr34kyn01535

#CONFIG
INSTANCE_NAME=1
STEAMCMD_HOME="./steamcmd"
UNTURNED_HOME="./unturned"

#COLORS
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLLOW='\033[0;33m'
NC='\033[0m'

#Steam checks
STEAMCMD_API=$STEAMCMD_HOME/linux32/steamclient.so
UNTURNED_API=$UNTURNED_HOME/Unturned_Data/Plugins/x86/steamclient.so
printf "Steam: "
if [ -f $STEAMCMD_API ]; then
        if diff $STEAMCMD_API $UNTURNED_API >/dev/null ; then
                printf "${GREEN}UP TO DATE${NC}\n\n"
        else
                cp $STEAMCMD_API $UNTURNED_API
                printf "${YELLLOW}UPDATING${NC}\n\n"
        fi
else
        printf "${RED}NOT FOUND${NC}\n\n"
fi

cd $UNTURNED_HOME

if [ -f RocketLauncher.exe ]; then
        ulimit -n 2048
        mono RocketLauncher.exe $INSTANCE_NAME
else
        echo "RocketLauncher not found."
fi

The thing is that if I execute ./check.sh from /home/steam It works fine. The bad news is that the @reboot doesn’t work for me when I reboot my VPS.

screen -list doesn’t throw anything if I reboot.

I’ve tried multiple things but didn’t work, the last thing I changed was adding -d parameter in the screen commands so the server wouldn’t need a terminal to write down the start-up.

I’m not sure how much can be done here to make @reboot work as expected.

How can I make my scripts run on boot? Are there any other alternatives to CRON‘s @reboot?

Thanks in advance.

Solution

Take a look at the systemd.service manpage. It describes how to configure systemd to manage a service. I am sure you will find examples for your system in /usr/lib/systemd/system or similar paths.

In your case, the service would look somewhat like this:

[Unit]
Description=Unturned Game Server

[Install]
WantedBy=multi-user.target

[Service]
ExecStart=/bin/bash /home/steam/start.sh
Type=simple
User=steam
Group=steam
WorkingDirectory=/home/steam
Restart=on-failure

Put this in a file /etc/systemd/system/unturned.service. Then run systemctl daemon-reload (once, and whenever you change unturned.service to tell systemd to re-read the configuration) and systemctl start unturned.service to start the game server.

If that works as expected, you can use systemctl enable unturned.service to make sure it starts at boot.

A few notes on the options used:

• If start.sh is not supposed to run as user/group steam, edit appropriately.
• WantedBy in the Install section tells systemd which “target” (see man systemd.target) pulls the service in when you enable it using systemctl enable.
• Restart defines under which circumstances systemd will automatically restart the service. There are more restart-related options, which you may or may not want to change; see the systemd.service man page.

Answered By – Jonas Schäfer

This Answer collected from stackoverflow, is licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0