How to Handle SFTPError: Failure: Generic SFTP Errors and Server-Side Issues in Paramiko

SFTPError indicates generic SFTP transfer problems. These errors often originate on the server. This tutorial explains how to handle them.

Understanding SFTPError

SFTPError covers various SFTP-related issues. These can include permission problems or file not found. Server-side errors also trigger this.

Common Causes of SFTPError

Incorrect file paths are a frequent cause. Insufficient permissions on the server cause errors. Disk quota issues on the server can also cause this.

Handling the SFTPError Exception

Use try-except blocks to catch SFTPError exceptions. This prevents your program from crashing. It allows for proper error handling.

import paramiko

try:
    ssh = paramiko.SSHClient()
    ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    ssh.connect("your_hostname", username="your_username", password="your_password")
    sftp = ssh.open_sftp()
    sftp.get('/remote/path/nonexistent_file.txt', 'local_file.txt') # Example that will raise SFTPError
    sftp.close()
    ssh.close()
except paramiko.sftp_client.SFTPError as e:
    print(f"SFTPError: {e}")
except Exception as e:
    print(f"Other Error: {e}")

Checking Error Codes

SFTPError objects have an errno attribute. This provides more specific error information. This helps diagnose the root cause.

import paramiko

try:
    # ... (SFTP operations) ...
except paramiko.sftp_client.SFTPError as e:
    print(f"SFTPError: {e}")
    print(f"Error Number: {e.errno}") # Print the error number
    if e.errno == 2: # No such file
        print("File not found on the server.")
    # Handle other specific error numbers as needed
except Exception as e:
    print(f"Other Error: {e}")

Checking File Paths and Permissions

Double-check remote file paths for accuracy. Verify that the user has necessary permissions. This is a very common source of errors.

Server-Side Issues

Server-side issues can cause various SFTPError exceptions. Check server logs for more details. Contact the server administrator if needed.

Logging for Debugging

Implement proper logging to capture error details. This helps diagnose complex SFTP transfer issues. It is very useful for debugging.

import logging
import paramiko

logging.basicConfig(filename='sftp_errors.log', level=logging.ERROR)

try:
    # ... (SFTP operations) ...
except paramiko.sftp_client.SFTPError as e:
    logging.error(f"SFTPError: {e}")
except Exception as e:
    logging.exception("An unexpected error occurred:")