Transferring large files with Paramiko requires optimization. This tutorial covers techniques for efficient transfers. It improves transfer speed and reliability.

The paramiko.ssh_exception.AuthenticationException is a common hurdle when working with Paramiko, indicating that the SSH client failed to authenticate with the remote server. This can stem from various issues, ranging from simple credential mistakes to complex server configurations or key file problems. Debugging this exception requires a systematic approach.

The paramiko.ssh_exception.NoValidConnectionsError is a specific type of exception raised by Paramiko when it attempts to establish an SSH connection but fails to connect to any of the resolved IP addresses for the given hostname and port. This error essentially means: “I tried all the ways I know to connect to that server, and none of them worked.” It’s a strong indicator of underlying network connectivity or server reachability issues, rather than authentication problems. This error often wraps one or more lower-level socket errors (e.g., connection refused, host unreachable, timeout), which can be inspected to pinpoint the exact cause.

The SSHException: Key exchange negotiation failed is a common and often frustrating error encountered when using Paramiko to connect to an SSH server. This error indicates that the client (Paramiko) and the server could not agree on a common set of cryptographic algorithms for the SSH handshake. This usually boils down to a “cipher mismatch”, “key exchange algorithm mismatch”, or a “host key algorithm mismatch.” Modern SSH clients (like recent versions of OpenSSH and Paramiko) prioritize strong, modern cryptographic algorithms and often deprecate or disable older, weaker ones for security reasons. Conversely, older SSH servers might only support these deprecated…

SSHException: Incompatible ssh server (no acceptable ciphers) means cipher mismatch. Paramiko and the server don’t share ciphers. This tutorial explains how to solve it.

While it’s commonly used for connecting to remote servers, you can also use Paramiko to authenticate the local host itself, providing a secure way to automate local tasks.

socket.timeout occurs when a connection times out. This can happen during connection or command execution. This tutorial explains how to handle it.

ChannelException: EOF sent indicates the remote process finished. This signals the normal end of a command. This tutorial explains what it means.

SSHException: Channel closed in Paramiko means the SSH channel was torn down by the server or network mid‑session, so diagnosing Paramiko channel closed errors requires checking both server‑side logs and network interruptions like firewalls or idle timeouts. This tutorial explains how to diagnose this.

If you’ve hit the Paramiko ‘Socket is closed’ error during SSH operations, the underlying TCP connection has already been dropped by the server, network, or firewall before Paramiko can finish its work. This error can be frustrating, but it’s essential to understand why it occurs and how to deal with it.