Forward a Session's ports

Open a dev server running in a Session at the same port on localhost on your machine, so redirects, cookies and curl work as they would locally.

What you need

• The kndl command on your machine, installed from a Hub and signed in.
• A Session with something listening in it, such as a dev server.

See a Session’s Open ports

While something listens on a port in an Active Session, its header shows how many, such as 3 ports. Press it to see each port, the process holding it, and the kndl forward command for the Session.

Forward a Session

1. On your machine, run:

   kndl forward

2. Pick the Session with the arrow keys, and press Enter:

   Forward which Session?
   > 0b9256  claude/fix-login  owner/name  3000, 5173
     77ab12  Docs  owner/name  no open ports
   Up and down to choose, Enter to forward, Esc to quit

3. The CLI lists each port it forwards:

   Forwarding 0b9256 claude/fix-login · owner/name · Active
     http://localhost:3000    bun server · 1 connection
     http://localhost:5173    node vite
   Esc: forward another Session · Ctrl-C: stop

4. Open http://localhost:5173 in your browser.

Ports that open or close in the Session later are added and removed as they do. Esc goes back to the picker. Ctrl-C stops forwarding.

Skip the picker

Name the Session by its id, the start of its id, or its URL:

kndl forward 0b9256

Choose the ports

Forward only some ports by naming them after the Session:

kndl forward 0b9256 5173 3000

Forward a Session’s port to a different port on your machine with <session port>:<local port>:

kndl forward 0b9256 3000:3100

An app that redirects to its own address, as an OAuth sign-in does, only works on the same port.

Let other devices reach it

By default, only your machine reaches the ports. To let a phone or another device on your network reach them, pass --bind:

kndl forward 0b9256 --bind 0.0.0.0

Caution

Anyone who can reach that address on your network can use the ports, without signing in to the Hub.

While it forwards

• The Session shows you in Here now as forwarding from your machine.
• The Session stays awake while a forward is connected.
• Forwarding an Asleep Session you started wakes it. Anyone else’s forward of it is told it’s Asleep, and that only its Creator can wake it.
• If the connection to the Hub drops, the CLI reconnects on its own.

If a port is already taken on your machine, the CLI says which process holds it and keeps retrying. See Commands for every option.

Next steps

Install the CLI from a HubGet the kndl command on your laptop.

Manage a SessionKeep a Session awake for a dev server.