IRC (alternate)
What is Port 6660?
Port 6660 is one of the commonly used alternate ports for IRC (Internet Relay Chat). While the IANA-assigned port for IRC is 194, the port range 6660-6669 has become the de facto standard for IRC server connections. This range was adopted because port 194 requires root privileges on Unix systems, and IRC servers typically run as unprivileged users. Port 6660 is often the first port in the IRC range that servers listen on, with 6667 being the most commonly used. IRC networks like Libera.Chat, OFTC, and EFnet listen on multiple ports in this range to provide connection options for users behind various firewall configurations.
Common Uses
- IRC server connections
- Alternative IRC client connections
- IRC bouncer (BNC) connections
- IRC network peering
Technical Details
Copy-paste commands to check port 6660 (IRC (alternate)) from your terminal
Test connectivity
nc -zv example.com 6660
curl -v --max-time 5 http://example.com:6660/
telnet example.com 6660
nmap -p 6660 -sV example.com
(echo > /dev/tcp/example.com/6660) 2>/dev/null && echo "open" || echo "closed"
Open port in firewall
sudo ufw allow 6660/tcp
sudo iptables -A INPUT -p tcp --dport 6660 -j ACCEPT
sudo firewall-cmd --permanent --add-port=6660/tcp && sudo firewall-cmd --reload
Security Considerations
IRC on ports 6660-6669 is unencrypted. Use port 6697 for TLS-encrypted IRC connections. IRC can be used as a covert command-and-control channel. Monitor for unexpected IRC traffic. Enable SASL authentication for IRC access.
Popular Ports Reference
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