all Python 3socketexception

socket.gaierror

exceptions

An address resolution error from getaddrinfo() and getnameinfo(): name not found, DNS unreachable, family unsupported.

Syntax

except socket.gaierror as e: ...

A subclass of OSError but not of ConnectionError: 'could not find the address' is a different failure from 'the server refused', and a ConnectionError handler will not catch it. Its errno is an EAI_* code, negative on Linux (-2 for 'name not found') and different on macOS, so compare with constants like socket.EAI_NONAME, never with numbers.

Examples

import socket
try:
    socket.getaddrinfo('not-an-ip', 80, flags=socket.AI_NUMERICHOST)
except socket.gaierror as e:
    print(e.errno == socket.EAI_NONAME)  # → True
    print(isinstance(e, OSError), isinstance(e, ConnectionError))  # → True False

See also

Common errors

Open in the full glossarydocs.python.orgReport an inaccuracy