UnoDOS pc64

Log in to another computer from UnoDOS, run commands on it and see the output, using the same SSH the rest of the world uses. Keys and saved connections live on this machine and survive a restart.

The SSH client on first run. The Manage tab holds two panes - your saved connections and your keys - and the + button beside the tabs opens a connection to whichever session is selected. Each connection gets its own tab.

What it can talk to

Any current OpenSSH server, and anything else that speaks the same modern set: curve25519-sha256 for key exchange, ssh-ed25519 host and user keys, aes256-ctr encryption and hmac-sha2-256 for integrity. It has been tested against OpenSSH 9.5 and 9.6.

Getting a key

SSH identifies you by a key rather than a password. You can either make one here or bring one you already have.

  1. Open SSH from the Start menu or the desktop.
  2. To make a new key, use the Keys pane. The public half is what you give to the other computer.
  3. To use an existing key, copy its private key file onto a disk UnoDOS can read and import it. Keys are listed as (open) or (locked) depending on whether they need a passphrase.
Importing a protected keyAn OpenSSH private key that was saved with a passphrase cannot be imported yet - that format needs a password-hashing function UnoDOS does not carry. Export a copy with no passphrase if you want to bring it across, and keep that copy somewhere safe.

Saving a connection

A saved session records the machine name or address, the port, the user name to log in as, and which of your keys to use. Select it in the Sessions pane and press + to connect. A new tab opens with the session running in it; close the tab to hang up. The Manage tab cannot be closed - it is where you always come back to.

Host keys and what a warning means

Every server proves who it is with its own key. The first time you connect to a machine, UnoDOS records that key and says so. On later visits it checks the key matches.

A changed host keyIf the key has CHANGED, the client refuses to connect and says so in red. That can mean the server was legitimately rebuilt - or that something is impersonating it. Do not work around the warning until you know which; find out from the machine's owner, then remove the stored key and connect again to record the new one.

Automation

The same client is available to the remote-control channel, so a script driving one UnoDOS machine can log in to others and run commands there. See Remote control & automation.

What it does not do yet

  • No file transfer (no SFTP or SCP) and no port forwarding.
  • The terminal shows plain text. Programs that draw with cursor-control codes - a full-screen text editor, for instance - will not display correctly.
  • Connecting uses keys that have no passphrase; the app cannot prompt for one yet.
  • Ed25519 keys only, for both host and user keys.