Connect to your box over SSH

Every box takes SSH at ssh <box>@ssh.detachbox.com with the keys on your account. Add a key once and every box you own lets it in. Port forwarding, rsync and Remote-SSH in VS Code or Cursor work through the same address.

Add your SSH key

Boxes let in keys only, no passwords.

1. On your computer, print your public key:

   cat ~/.ssh/id_ed25519.pub
   

   No key yet? Create one with ssh-keygen -t ed25519.

2. In the dashboard, open SSH keys and pick Add SSH key.

3. Paste the whole line. It starts with ssh-ed25519, ssh-rsa or ecdsa-sha2.

4. Name the key, for example laptop. Leave the name empty to use the key's comment.

5. Pick Add SSH key.

Every key on your account opens every box you own, and each box picks the key up by itself. An account holds up to 50 keys.

Paste the .pub file only. The dashboard refuses a private key, and the private half never leaves your laptop.

Import your keys from GitHub

1. On SSH keys, pick Import from GitHub.
2. Enter your GitHub username.
3. Pick Import keys.

The dashboard takes every public key listed at github.com/<username>.keys. Keys already on your account are skipped.

Connect to a box

Copy the command from Connect over SSH on the box's Overview, then run it:

ssh [email protected]

You land in the box as the dev user. To skip typing the address, add the box to ~/.ssh/config:

Host my-box
  HostName ssh.detachbox.com
  User my-box

Then ssh my-box connects.

Verify the host key

On the first connection, SSH asks you to trust the host. Open Verify the host key under Connect over SSH and compare the fingerprint there with the one SSH prints. Answer yes only when they match.

Join your terminal tabs over SSH

Each browser tab is a tmux session on the box, so SSH reaches the same sessions:

tmux ls
tmux attach -t <session>

Detach with Ctrl+B then D. The agent keeps working.

Run a command on the box

ssh [email protected] 'docker ps'

The DETACHBOX_* variables from box.env load in these shells too. Agents lists them.

Forward a dev server or a database

Forward a port to your computer with -L:

ssh -L 3000:localhost:3000 [email protected]

Open localhost:3000 on your laptop to see the app running inside the box. The box page has this command under Forward a dev server.

For a database or any raw TCP port, forward without a shell:

ssh -N -L 5432:localhost:5432 [email protected]

For web apps, a preview URL needs no tunnel and opens on your phone too.

Copy a folder with rsync

The browser terminal refuses folders. Copy a folder with rsync:

rsync -az ./my-folder/ [email protected]:~/my-folder/

Swap the two paths to copy from the box to your computer.

Open the box in VS Code or Cursor

Both editors connect through their Remote-SSH extension, with your own key.

1. Add your key on SSH keys.
2. In the editor, connect to the host [email protected].

From the browser terminal, open a file path in the viewer and pick Open in VS Code or Open in Cursor. The editor opens that file at that line over Remote-SSH. If it can't connect, add your key under SSH keys.

Remove a key

1. On SSH keys, open the key's menu and pick Delete key.
2. Confirm.

Every box stops accepting the key. Deleting your only key locks SSH until you add another. The browser terminal keeps working.

Permission denied?

Permission denied (publickey) means the box didn't get a key it knows. Check that the key on your computer is one listed on SSH keys, and that the user in the command is the box name. Troubleshooting has more fixes.