Using Paramiko for SSH Connections, Command Execution, and File Operations in Python

Connecting to a remote server is typically done via the SSH (Secure Shell) protocol, and the Python library paramiko provides a convenient way to perform secure remote command execution and file transfer.

Password authentication example:

import paramiko
# Create an SSH client object
ssh = paramiko.SSHClient()
# Automatically add unknown host keys
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
# Connect to the remote server
ssh.connect(hostname='your_server_ip', port=22, username='username', password='password')
# Execute a remote command
stdin, stdout, stderr = ssh.exec_command('ls -l')
stdout_result = stdout.read().decode()
stderr_result = stderr.read().decode() if stderr.channel.recv_exit_status() != 0 else ""
print(f"Standard output: {stdout_result}")
print(f"Error output: {stderr_result}")
# Close the connection
ssh.close()

Public‑key (private‑key) authentication example:

# Load a local private key file
private_key = paramiko.RSAKey.from_private_key_file('/path/to/your/private_key.pem')
# Connect using the private key
ssh.connect(hostname='your_server_ip', port=22, username='username', pkey=private_key)
# Subsequent operations are the same as above

File operation example (create, upload, download, edit, delete):

import paramiko
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect(hostname='your_server_ip', port=22, username='username', password='password')
# Create a new file on the remote server
ssh.exec_command("touch /path/to/newfile.txt")
# Upload a local file to the remote server
sftp = ssh.open_sftp()
local_file_path = '/path/to/localfile.txt'
remote_file_path = '/path/to/remotefile.txt'
sftp.put(local_file_path, remote_file_path)
# Download the file back
sftp.get(remote_file_path, local_file_path)
# Edit the remote file (example: write a line)
ssh.exec_command('echo "Hello World" > /path/to/remotefile.txt')
# Delete the remote file
ssh.exec_command("rm /path/to/remotefile.txt")
# Close SFTP and SSH connections
sftp.close()
ssh.close()

Replace placeholder values such as server IP, usernames, passwords, and file paths with actual data; consider storing sensitive credentials in environment variables or secure vaults, and prefer key‑based authentication for better security.