How to Auto-Restart Failed Services

Prerequisites

Before configuring auto-restart, make sure you have:

• SSH access to your VPS
• Root or sudo privileges

Method 1: Modify Existing Service File

Connect to your VPS:

ssh hxroot@YOUR_SERVER_IP -p 22

Edit the service override:

sudo systemctl edit nginx

Add the following:

[Service]
Restart=on-failure
RestartSec=5s

Save and exit. Then reload:

sudo systemctl daemon-reload

Restart the service:

sudo systemctl restart nginx

Restart Policies Explained

• no – Never restart
• on-success – Restart only if exit code 0
• on-failure – Restart on non-zero exit, timeout, or crash (recommended)
• always – Always restart (even if stopped manually)
• on-abnormal – Restart on signal, timeout, or watchdog

Additional Useful Options

[Service]
Restart=on-failure
RestartSec=10s
StartLimitInterval=200s
StartLimitBurst=5

These settings limit restart attempts to 5 times within 200 seconds (prevents infinite restart loops).

Method 2: Create a Complete Service File

sudo nano /etc/systemd/system/myapp.service

[Unit]
Description=My Application
After=network.target

[Service]
Type=simple
User=www-data
ExecStart=/usr/bin/node /opt/myapp/app.js
Restart=on-failure
RestartSec=10
StartLimitInterval=300
StartLimitBurst=5

[Install]
WantedBy=multi-user.target

Test Auto-Restart

Find PID of the service:

systemctl status nginx | grep PID

Kill the process:

sudo kill -9 PID

Wait a few seconds, then check:

systemctl status nginx

The service should have restarted automatically.

View Restart Count

systemctl show nginx -p NRestarts

Disable Auto-Restart for a Service

sudo systemctl edit nginx

Set:

[Service]
Restart=no

Then:

sudo systemctl daemon-reload