coder/docs/networking/port-forwarding.md

Port Forwarding

Port forwarding lets developers securely access processes on their Coder workspace from a local machine. A common use case is testing web applications in a browser.

There are three ways to forward ports in Coder:

• The coder port-forward command
• Dashboard
• SSH

The coder port-forward command is generally more performant.

The coder port-forward command

This command can be used to forward TCP or UDP ports from the remote workspace so they can be accessed locally. Both the TCP and UDP command line flags (--tcp and --udp) can be given once or multiple times.

The supported syntax variations for the --tcp and --udp flag are:

• Single port with optional remote port: local_port[:remote_port]
• Comma separation local_port1,local_port2
• Port ranges start_port-end_port
• Any combination of the above

Examples

Forward the remote TCP port 8080 to local port 8000:

coder port-forward myworkspace --tcp 8000:8080

Forward the remote TCP port 3000 and all ports from 9990 to 9999 to their respective local ports.

coder port-forward myworkspace --tcp 3000,9990-9999

For more examples, see coder port-forward --help.

Dashboard

To enable port forwarding via the dashboard, Coder must be configured with a wildcard access URL.

Use the "Port forward" button in the dashboard to access ports running on your workspace.

SSH

First, configure SSH on your local machine. Then, use ssh to forward like so:

ssh -L 8080:localhost:8000 coder.myworkspace

You can read more on SSH port forwarding here.