gh-127319: Disable port reuse on HTTP, XMLRPC, and logging TCP servers (GH-135405)

Prior to issue #120485 these servers did not allow port reuse, which
makes sense as the behavior of port reuse is surprising if you're not
expecting it. It's unclear to me why these services were switched to
allow port reuse, but I believe the desired behavior (unless subclasses
opt in) is to not allow port reuse.

See also: https://bugzilla.redhat.com/show_bug.cgi?id=2323170

Author: jeremycline

Lib/http/server.py

@@ -115,7 +115,7 @@
 class HTTPServer(socketserver.TCPServer):
 
     allow_reuse_address = True    # Seems to make sense in testing environment
-    allow_reuse_port = True
+    allow_reuse_port = False
 
     def server_bind(self):
         """Override server_bind to store the server name."""

Lib/logging/config.py

@@ -1018,7 +1018,7 @@ class ConfigSocketReceiver(ThreadingTCPServer):
         """
 
         allow_reuse_address = True
-        allow_reuse_port = True
+        allow_reuse_port = False
 
         def __init__(self, host='localhost', port=DEFAULT_LOGGING_CONFIG_PORT,
                      handler=None, ready=None, verify=None):

Lib/test/test_logging.py

@@ -1036,7 +1036,7 @@ class TestTCPServer(ControlMixin, ThreadingTCPServer):
     """
 
     allow_reuse_address = True
-    allow_reuse_port = True
+    allow_reuse_port = False
 
     def __init__(self, addr, handler, poll_interval=0.5,
                  bind_and_activate=True):

Lib/xmlrpc/server.py

@@ -578,7 +578,7 @@ class SimpleXMLRPCServer(socketserver.TCPServer,
     """
 
     allow_reuse_address = True
-    allow_reuse_port = True
+    allow_reuse_port = False
 
     # Warning: this is for debugging purposes only! Never set this to True in
     # production code, as will be sending out sensitive information (exception

Misc/NEWS.d/next/Core_and_Builtins/2025-06-11-15-08-10.gh-issue-127319.OVGFSZ.rst

@@ -0,0 +1,3 @@
+Set the ``allow_reuse_port`` class variable to ``False`` on the XMLRPC,
+logging, and HTTP servers. This matches the behavior in prior Python
+releases, which is to not allow port reuse.