Remote access

Remote access lets another device use the sessions on this computer. A paired device can follow sessions live, send messages, answer permission requests, start and rename sessions, attach photos and other files, open images, videos and project files, and see the project’s changes.

Everything stays on this computer. The device connects straight to it, on the same network or over a VPN such as Tailscale, end-to-end encrypted, with no account and nothing passing through a cloud. A browser is one such device.

To use this computer from a browser on any other network, sign it in to your Kettu account and open the web client at app.kettu.sh: see From any network.

Turning it on

Open Settings › Remote access and turn on Remote access. Kettu starts listening on a port, and the status under the switch reads On, the port it listens on, and how many devices are online.

• Devices reach this computer only while Kettu runs. While remote access is on, Kettu keeps running in the background after you close its window, and Settings › General › Run in the background stays on.
• This computer’s name is the name devices show, the computer’s own name until you change it.
• Turning remote access off disconnects every device. Paired devices stay in the list, where you can still rename and remove them; adding one waits until remote access is on again.

If Kettu cannot use the port, for example because another program has it, the status says it could not listen on the port, with Change port and Retry.

Direct connections

Direct connections turn on with remote access: they are how devices reach this computer. The Direct group sets where they come in.

Devices get every address with the pairing code and try them all at once. A device on the same Wi-Fi or wired network uses a private address, and one on the same VPN the VPN address.

When you change the port, devices online at that moment learn the new one. Devices that are not connected only know the old port and cannot connect until you add them again, and a port you forward has to change too.

Pairing a device

Click Add device… in the Devices group. Kettu shows a one-time code as a QR code and as a link, with Copy. Open with picks who the code is for:

The code adds one device and expires in 5 minutes. It also stops working once a device has used a wrong code 5 times, once you reject a device, when you close Add device or open it somewhere else, and when remote access stops. New code makes another.

When a device connects with the code, Kettu asks Add this device?, with the name the device gave, which you can change here or later on the device. Choose Add only if it is the device in your hand that just used the code: someone who photographs the code cannot connect unless you choose Add here. Reject voids the code.

Allow terminal

Allow terminal lets paired devices open this computer’s terminals. It is off by default.

With it on, a device can run any command on this computer, beyond what an agent asks to run, so turn it on only when you need it. Turning it off closes the devices’ terminals; the terminals keep running on this computer.

Each device

The Devices list shows every paired device, with Online or when it last connected. Click one to open its page:

• Device says when it joined, from a scanned code or a pasted link, and when it last connected.
• Activity lists the last 30 days: when it connected, the sessions it started, archived or deleted, the terminals it opened and closed, and renames. Only what happened is kept, never content, commands or addresses, and at most 500 events.
• Rename changes its name.
• Remove this device disconnects it at once and its key stops working; the session list it cached is cleared the next time it connects, and it is told it was removed. To use it again, add it again.

A device that has not connected for 90 days is removed, and the list warns you when one is close; connecting once keeps it.

Reset remote access removes every device and gives this computer a new identity, so every device has to be added again.

Settings › Hosts

Settings › Hosts lists the hosts Kettu on this computer connects to, starting with This computer. To add another computer that runs Kettu:

Each host shows the version of Kettu it runs, how it is reached, such as Direct and the address, and whether it is Online, Connecting… or Offline. Click one for its page:

• Addresses are where this computer looks for it. The host sends its latest addresses each time it connects; Edit… changes them when it changed its port and has not connected since.
• Name, under This computer on and the host’s name, is how that host lists this computer. It can be changed while the host is online.
• Remove from this computer stops connecting to it. Nothing changes on that host, which keeps listing this computer among its devices until you remove it there.

If the host removes this computer, its page says so, with Add again….

This page connects to each host and shows whether it is reachable. The window does not list another host’s sessions.

When a device cannot connect

• Check that Kettu is running on this computer with remote access on, and that both devices are on the same network or the same VPN.
• For an address you added yourself, check that the port forwarding still works.
• If the port changed while the device was offline, or after you reset remote access, add the device again.
• If the code expired or was used, click New code.