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Transfer files to and from a remote host with sftp, both interactively for ad hoc work and non-interactively via a batch script for automation, including resuming interrupted transfers.

Run a single remote command non-interactively from a script or CI pipeline over ssh, quoting it correctly, suppressing interactive prompts, forcing a TTY only when needed, and propagating the remote exit code.

Speed up repeated SSH/SCP/SFTP connections to the same host by reusing one cached network connection (multiplexing) via ControlMaster/ControlPath/ControlPersist, and detect dead connections with ServerAlive keepalives.

Connect to a private server that is only reachable through an intermediate bastion/jump host, using SSH ProxyJump so the client transparently tunnels through one or more hops.

Set up an ad hoc encrypted SOCKS proxy through an SSH server with ssh -D, then route arbitrary client traffic (browsers, curl, etc.) through it so requests appear to originate from the remote host.

Expose a service running on your local machine (e.g. a local dev web server) on a remote host by forwarding a port on that remote host back to your local port using ssh -R, so processes on the remote side can reach your local service.

Reach a service that is only accessible from a remote host (e.g. a database bound to localhost on a remote server) by forwarding a local TCP port through an SSH tunnel to that remote-only service using ssh -L.

Create reusable per-host SSH connection aliases in ~/.ssh/config so a short name like 'ssh myhost' expands to the correct hostname, user, port, and identity file instead of typing full connection details every time.

Systematically diagnose a failing ssh connection or authentication attempt using client-side verbosity flags and server-side sshd log/debug output, and fix the most common causes (key permissions, wrong identity offered, host-side StrictModes).

Resolve ssh's "REMOTE HOST IDENTIFICATION HAS CHANGED" / host-key verification failure by safely updating known_hosts, distinguishing a legitimate host-key rotation from a possible man-in-the-middle attack.

Install a locally generated SSH public key on a remote server's authorized_keys so subsequent logins for that account succeed via public-key authentication instead of a password.

Generate a modern Ed25519 SSH keypair with ssh-keygen and load the private key into a running ssh-agent so it can be used for public-key authentication without repeated passphrase prompts.