Here is an example error from the log for unsubscribe all operation.
[2025-12-15 15:41:02 +0000] [1022464] [ERROR] Error handling request /mailman3/lists/uclucu-members.ucl.ac.uk/unsubscribe_all Traceback (most recent call last): File "/data/mailman/venv/lib64/python3.12/site-packages/gunicorn/workers/sync.py", line 134, in handle self.handle_request(listener, req, client, addr) File "/data/mailman/venv/lib64/python3.12/site-packages/gunicorn/workers/sync.py", line 177, in handle_request respiter = self.wsgi(environ, resp.start_response) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/wsgi.py", line 124, in __call__ response = self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/base.py", line 140, in get_response response = self._middleware_chain(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/allauth/account/middleware.py", line 33, in middleware response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/utils/deprecation.py", line 134, in __call__ response = response or self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django_mailman3/middleware/__init__.py", line 36, in __call__ response = self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/postorius/middleware.py", line 42, in __call__ return self.get_response(request) ^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/exception.py", line 55, in inner response = get_response(request) ^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/core/handlers/base.py", line 197, in _get_response response = wrapped_callback(request, *callback_args, **callback_kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/django/contrib/auth/decorators.py", line 23, in _wrapper_view return view_func(request, *args, **kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/postorius/auth/decorators.py", line 43, in wrapper return fn(*args, **kwargs) ^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/postorius/views/list.py", line 1496, in remove_all_subscribers mlist.unsubscribe(names.email) File "/data/mailman/venv/lib64/python3.12/site-packages/mailmanclient/restobjects/mailinglist.py", line 519, in unsubscribe response, json = self._connection.call(path, data, method='DELETE') ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/mailmanclient/restbase/connection.py", line 145, in call response = request(**params, auth=self.auth) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/requests/api.py", line 59, in request return session.request(method=method, url=url, **kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/requests/sessions.py", line 589, in request resp = self.send(prep, **send_kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/requests/sessions.py", line 703, in send r = adapter.send(request, **kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/requests/adapters.py", line 644, in send resp = conn.urlopen( ^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/urllib3/connectionpool.py", line 787, in urlopen response = self._make_request( ^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/urllib3/connectionpool.py", line 534, in _make_request response = conn.getresponse() ^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/urllib3/connection.py", line 565, in getresponse httplib_response = super().getresponse() ^^^^^^^^^^^^^^^^^^^^^ File "/usr/lib64/python3.12/http/client.py", line 1430, in getresponse response.begin() File "/usr/lib64/python3.12/http/client.py", line 331, in begin version, status, reason = self._read_status() ^^^^^^^^^^^^^^^^^^^ File "/usr/lib64/python3.12/http/client.py", line 292, in _read_status line = str(self.fp.readline(_MAXLINE + 1), "iso-8859-1") ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/usr/lib64/python3.12/socket.py", line 720, in readinto return self._sock.recv_into(b) ^^^^^^^^^^^^^^^^^^^^^^^ File "/data/mailman/venv/lib64/python3.12/site-packages/gunicorn/workers/base.py", line 204, in handle_abort sys.exit(1) SystemExit: 1
From: Washington Odhiambo <odhiambo@gmail.com> Sent: 17 December 2025 07:34 To: mailman-users@mailman3.org Cc: Reilly, Liam <l.reilly@ucl.ac.uk> Subject: Re: [MM3-users] Mass operations on large list - Internal Server Error
⚠ Caution: External sender
On Wed, Dec 17, 2025 at 10:25 AM Liam Reilly <l.reilly@ucl.ac.uk<mailto:l.reilly@ucl.ac.uk>> wrote: Hi,
A list owner has reported that their list page for list of 3460 members crashes with "internal server error" when attempting to do mass operations such as unsubscribe all or large mass subscribe of many members.
Has anyone else experienced this?
And what did mailmanweb.log file say about this?
-- Best regards, Odhiambo WASHINGTON, Nairobi,KE +254 7 3200 0004/+254 7 2274 3223 In an Internet failure case, the #1 suspect is a constant: DNS. "Oh, the cruft.", egrep -v '^$|^.*#' ¯\_(ツ)_/¯ :-) [How to ask smart questions: http://www.catb.org/~esr/faqs/smart-questions.html]