Linux autostart ssr with systemd unit

• Autostart ssr with systemd unite
  • Issue 1: Run systemd unit as normal user
  • Issue 2: Run ssr script after network is ready
• References

Autostart ssr with systemd unite

First, create a Systemd service file - /etc/systemd/system/ssr.service as below:

[Unit]
After=network.service

[Service]
ExecStart=/usr/local/bin/ssr_start
ExecStop=/usr/local/bin/ssr_stop

[Install]
WantedBy=default.target

After: Instructs systemd on when the script should be run
ExecStart: This field provides a full path to the actual script to be executed on startup
ExecStop: This field provides a full path to the actual script to be executed on stop WantedBy: Into what boot target the systemd unit should be installed

Note that, you can also directly use ssr script in ssr.service.

Then, create the script - /usr/local/bin/ssr_start and /usr/local/bin/ssr_stop as below:

#!/bin/bash

/home/mudongliang/bin/ssr start > /tmp/ssr.log 2>&1

#!/bin/bash

/home/mudongliang/bin/ssr stop > /tmp/ssr.log 2>&1

Finally, modify the permission of two files and reload systemd

chmod 644 /etc/systemd/system/ssr.service
chmod 755 /usr/local/bin/ssr_start
chmod 755 /usr/local/bin/ssr_stop

sudo systemctl daemon-reload
sudo systemctl enable ssr.service

Here you can use systemctl start ssr.service and systemctl stop ssr.service to test this unit.

Issue 1: Run systemd unit as normal user

We don’t this service is executed by root at boot, so running systemd unit as normal user is essential. Systemd provides User and Group to specify which user to run this system unit. Then our ssr_start.service changes like this (Replace XXX with your own username and group name)

[Unit]
After=network.service

[Service]
User=XXX
Group=XXX
ExecStart=/usr/local/bin/ssr_start
ExecStop=/usr/local/bin/ssr_stop
RemainAfterExit=yes

[Install]
WantedBy=default.target

Issue 2: Run ssr script after network is ready

Only network.service does not make sure network is really up. After google-searching, I found Reference 3 can help solve this issue.

[Unit]
Description=Run service as user mudongliang
Wants=network-online.target
After=network-online.target

[Service]
User=XXX
Group=XXX
ExecStart=/usr/local/bin/ssr_start
ExecStop=/usr/local/bin/ssr_stop
RemainAfterExit=yes

[Install]
WantedBy=default.target

References

[1] How to run script on startup on Ubuntu 20.04 Focal Fossa Server/Desktop

[2] How to run systemd service as specific user and group in Linux

[3] Running Services After the Network is up