DevErrors

SSH 'Host key has changed' error occurs when the remote server's SSH key fingerprint no longer matches what's stored locally. This is a security feature designed to prevent man-in-the-middle attacks. Common causes include server reinstallation, IP reassignment, DNS changes, or legitimate key rotation.

SSH authenticated you, but the server could not start your login shell. It usually means the user's shell is missing or invalid, the home directory or shell binary has bad permissions, the disk is full or read-only, or a security/PAM policy blocked the session.

The SSH client cannot reach the remote server on port 22 within the timeout period. The packet_write_poll error indicates the TCP connection attempt failed to establish. This typically means a firewall is blocking the connection, the SSH service isn't running, or there are network routing issues.

SSH prints this when the server declines to allocate a pseudo-terminal for an interactive session. The usual cause is a restricted key or sshd policy that forbids a TTY, not a broken server.

This error occurs when the SSH connection is unexpectedly terminated by the remote server during the authentication or communication phase. The server closes the TCP connection without properly completing the SSH protocol handshake, often due to server configuration issues, firewall blocking, or resource constraints.

This SSH warning appears when the host key for a remote server doesn't match the stored fingerprint in your known_hosts file, which can indicate DNS spoofing, server changes, or IP address reuse. Usually this is benign but requires verification.