🔗 TCP Port and Address

The CoolerControl daemon listens on a TCP port for connections, making the Web UI and REST API available. By default, it binds to the local loopback interface on port 11987.

Default Configuration

The default network settings are:

• Port: 11987 (HTTP/HTTPS)
• gRPC Port: 11988 (API)
• IPv4 Address: 127.0.0.1 (localhost)
• IPv6 Address: ::1 (localhost)

Configuration File

You can configure the daemon's bind address and port in the config file /etc/coolercontrol/config.toml:

sudo systemctl stop coolercontrold
sudo nano /etc/coolercontrol/config.toml
sudo systemctl start coolercontrold

[settings]
port = 11987
ipv4_address = "127.0.0.1"
ipv6_address = "::1"

Binding to All Interfaces

To allow connections from other machines on your network, bind to all interfaces:

[settings]
port = 11987
ipv4_address = "0.0.0.0"
ipv6_address = "::"

WARNING

Binding to 0.0.0.0 or :: exposes the daemon to your entire network. Ensure you have:

• Set a strong password via Access Protection
• Configured firewall rules to restrict access
• Considered using a proper certificate for SSL/TLS encryption

Binding to a Specific Interface

To bind to a specific network interface, use its IP address:

[settings]
port = 11987
ipv4_address = "192.168.1.100"  # Your machine's IP on the network

Environment Variables

You can also configure these via environment variables (useful in containerized or ephemeral setups): CC_PORT, CC_HOST_IP4, and CC_HOST_IP6. For example:

export CC_PORT=12000
export CC_HOST_IP4=0.0.0.0
export CC_HOST_IP6=::

For systemd-managed environments, you can also create a drop-in override to persist these settings:

sudo systemctl edit coolercontrold

Then add:

[Service]
Environment = "CC_PORT=12000"
Environment = "CC_HOST_IP4=0.0.0.0"
Environment = "CC_HOST_IP6=::"

Finally, reload and restart:

sudo systemctl daemon-reload
sudo systemctl restart coolercontrold

Firewall Configuration

If you're exposing the daemon on your network, configure your firewall to allow access:

UFW (Ubuntu/Debian)

sudo ufw allow 11987/tcp

firewalld (Fedora/RHEL)

sudo firewall-cmd --permanent --add-port=11987/tcp
sudo firewall-cmd --reload

iptables

sudo iptables -A INPUT -p tcp --dport 11987 -j ACCEPT
sudo iptables-save > /etc/iptables/rules.v4

Port Conflicts

If port 11987 is already in use, you can change it to any available port. Common alternatives include 8080, 8888, or any port above 1024 that doesn't require root privileges.

See Also

• Remote Access - Configure remote access to CoolerControl
• Access Protection - Set a strong password
• SSL/TLS - Secure your daemon with TLS encryption
• Configuration Files - Learn about daemon configuration files