Found today while debugging Swift on Bullseye in Cloud VPS. It looks like `getaddrinfo` from `eventlet` times
out:out (e.g. on `ms-be-01.swift.eqiad1.wikimedia.cloud`)
```
$ python3 -c 'from eventlet.green import socket ; print(socket.getaddrinfo("ms-fe-02.swift.eqiad1.wikimedia.cloud", 11211, socket.AF_UNSPEC, socket.SOCK_STREAM))'
Traceback (most recent call last):
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 435, in resolve
return _proxy.query(name, rdtype, raise_on_no_answer=raises,
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 391, in query
return end()
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 370, in end
raise result[1]
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 351, in step
a = fun(*args, **kwargs)
File "/usr/lib/python3/dist-packages/dns/resolver.py", line 1089, in query
return self.resolve(qname, rdtype, rdclass, tcp, source,
File "/usr/lib/python3/dist-packages/dns/resolver.py", line 1043, in resolve
timeout = self._compute_timeout(start, lifetime)
File "/usr/lib/python3/dist-packages/dns/resolver.py", line 950, in _compute_timeout
raise Timeout(timeout=duration)
dns.exception.Timeout: The DNS operation timed out after 5.107318878173828 seconds
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "<string>", line 1, in <module>
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 528, in getaddrinfo
qname, addrs = _getaddrinfo_lookup(host, family, flags)
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 501, in _getaddrinfo_lookup
raise err
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 490, in _getaddrinfo_lookup
answer = resolve(host, qfamily, False, use_network=use_network)
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 443, in resolve
raise EAI_EAGAIN_ERROR
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 490, in _getaddrinfo_lookup
answer = resolve(host, qfamily, False, use_network=use_network)
File "/usr/lib/python3/dist-packages/eventlet/support/greendns.py", line 443, in resolve
raise EAI_EAGAIN_ERROR
socket.gaierror: [Errno -3] Lookup timed out
```
Whereas non-eventlet works as expected
```
$ python3 -c 'import socket ; print(socket.getaddrinfo("ms-fe-02.swift.eqiad1.wikimedia.cloud", 11211, socket.AF_UNSPEC, socket.SOCK_STREAM))'
[(<AddressFamily.AF_INET: 2>, <SocketKind.SOCK_STREAM: 1>, 6, '', ('172.16.3.119', 11211))]
```