Networking & DevOpsHigh Severity
ERR_CONNECTION_REFUSED: Fix Web Server Connection Rejection
Applies to: Google Chrome, Linux Servers, Docker
Safety & Usage Advisory
Can you still drive / use device? Cannot establish TCP handshake with destination port.
Estimated Repair Cost
$0
$0 (Developer / Server Fix)
Diagnostic Category
Networking & DevOps
Google Chrome, Linux Servers, Docker
Fix Difficulty
Beginner
~30-60 Mins Required
Common Symptoms
- Chrome error page displaying ERR_CONNECTION_REFUSED
- cURL returns `Failed to connect to host port: Connection refused`
Root Causes
- Web server process (Nginx/Apache/Node) is stopped or crashed
- Port binding mismatch in Docker container (`-p 3000:3000`)
- UFW / iptables firewall rejecting incoming port 80/443 traffic
Step-by-Step Instructions to Fix ERR_REFUSED
1
Verify Port Listening Status
Run `sudo netstat -tulpn | grep -E '80|443|3000'` or `lsof -i :3000` to verify the process is listening.
2
Check Firewall Rules
Run `sudo ufw status` and allow HTTP/HTTPS with `sudo ufw allow 80/tcp && sudo ufw allow 443/tcp`.
3
Restart Backend Application
Restart application container or PM2 service.
How to Prevent ERR_REFUSED in the Future
- Configure auto-restart policies on all production Docker containers (`restart: unless-stopped`)
ERR_REFUSED Troubleshooting FAQs
Usually no. It means the server IP was reached, but no listening software accepted the connection on that port.