diff --git a/fail2ban/server/filter.py b/fail2ban/server/filter.py
index ac64fb86..13538c66 100644
--- a/fail2ban/server/filter.py
+++ b/fail2ban/server/filter.py
@@ -100,6 +100,10 @@ class Filter(JailThread):
 	def __repr__(self):
 		return "%s(%r)" % (self.__class__.__name__, self.jail)
 
+	@property
+	def jailName(self):
+		return (self.jail is not None and self.jail.name or "~jailless~")
+
 	def clearAllParams(self):
 		""" Clear all lists/dicts parameters (used by reloading)
 		"""
@@ -135,7 +139,7 @@ class Filter(JailThread):
 			if "\n" in regex.getRegex() and not self.getMaxLines() > 1:
 				logSys.warning(
 					"Mutliline regex set for jail %r "
-					"but maxlines not greater than 1", self.jail.name)
+					"but maxlines not greater than 1", self.jailName)
 		except RegexException as e:
 			logSys.error(e)
 			raise e
@@ -420,7 +424,7 @@ class Filter(JailThread):
 
 	def logIgnoreIp(self, ip, log_ignore, ignore_source="unknown source"):
 		if log_ignore:
-			logSys.info("[%s] Ignore %s by %s" % (self.jail.name, ip, ignore_source))
+			logSys.info("[%s] Ignore %s by %s" % (self.jailName, ip, ignore_source))
 
 	def getIgnoreIP(self):
 		return self.__ignoreIpList
@@ -491,7 +495,7 @@ class Filter(JailThread):
 				if self.inIgnoreIPList(ip, log_ignore=True):
 					continue
 				logSys.info(
-					"[%s] Found %s - %s", self.jail.name, ip, datetime.datetime.fromtimestamp(unixTime).strftime("%Y-%m-%d %H:%M:%S")
+					"[%s] Found %s - %s", self.jailName, ip, datetime.datetime.fromtimestamp(unixTime).strftime("%Y-%m-%d %H:%M:%S")
 				)
 				tick = FailTicket(ip, unixTime, lines, data=fail)
 				self.failManager.addFailure(tick)
diff --git a/fail2ban/server/filtergamin.py b/fail2ban/server/filtergamin.py
index a8d03ebd..106e4c0f 100644
--- a/fail2ban/server/filtergamin.py
+++ b/fail2ban/server/filtergamin.py
@@ -132,7 +132,7 @@ class FilterGamin(FileFilter):
 			Utils.wait_for(lambda: not self.active or self._handleEvents(),
 				self.sleeptime)
 			self.ticks += 1
-		logSys.debug(self.jail.name + ": filter terminated")
+		logSys.debug("[%s] filter terminated", self.jailName)
 		return True
 
 	def stop(self):
diff --git a/fail2ban/server/filterpoll.py b/fail2ban/server/filterpoll.py
index d0660f15..abf16e1b 100644
--- a/fail2ban/server/filterpoll.py
+++ b/fail2ban/server/filterpoll.py
@@ -123,9 +123,7 @@ class FilterPoll(FileFilter):
 				except FailManagerEmpty:
 					self.failManager.cleanup(MyTime.time())
 				self.__modified = False
-		logSys.debug(
-			(self.jail is not None and self.jail.name or "jailless") +
-					 " filter terminated")
+		logSys.debug("[%s] filter terminated", self.jailName)
 		return True
 
 	##
diff --git a/fail2ban/server/filterpyinotify.py b/fail2ban/server/filterpyinotify.py
index 9b444844..6ddf1691 100644
--- a/fail2ban/server/filterpyinotify.py
+++ b/fail2ban/server/filterpyinotify.py
@@ -198,7 +198,7 @@ class FilterPyinotify(FileFilter):
 			prcevent, timeout=self.sleeptime)
 		self.__notifier.check_events = self.__check_events
 		self.__notifier.start()
-		logSys.debug("pyinotifier started for %s.", self.jail.name)
+		logSys.debug("[%s] filter started (pyinotifier)", self.jailName)
 		return True
 
 	##
@@ -206,15 +206,22 @@ class FilterPyinotify(FileFilter):
 
 	def stop(self):
 		super(FilterPyinotify, self).stop()
-
 		# Stop the notifier thread
 		self.__notifier.stop()
-		self.__notifier.join()			# to not exit before notifier does
-		self.__cleanup()				# for pedantic ones
+
+	##
+	# Wait for exit with cleanup.
+
+	def join(self):
+		self.__cleanup()
+		super(FilterPyinotify, self).join()
+		logSys.debug("[%s] filter terminated (pyinotifier)", self.jailName)
 
 	##
 	# Deallocates the resources used by pyinotify.
 
 	def __cleanup(self):
-		self.__notifier = None
+		if self.__notifier:
+			self.__notifier.join()			# to not exit before notifier does
+			self.__notifier = None
 		self.__monitor = None
diff --git a/fail2ban/server/filtersystemd.py b/fail2ban/server/filtersystemd.py
index a29085ba..310d15b3 100644
--- a/fail2ban/server/filtersystemd.py
+++ b/fail2ban/server/filtersystemd.py
@@ -130,7 +130,8 @@ class FilterSystemd(JournalFilter): # pragma: systemd no cover
 			self.resetJournalMatches()
 			raise
 		else:
-			logSys.info("Added journal match for: %r", " ".join(match))
+			logSys.info("[%s] Added journal match for: %r", self.jailName, 
+				" ".join(match))
 	##
 	# Reset a journal match filter called on removal or failure
 	#
@@ -138,7 +139,7 @@ class FilterSystemd(JournalFilter): # pragma: systemd no cover
 
 	def resetJournalMatches(self):
 		self.__journal.flush_matches()
-		logSys.debug("Flushed all journal matches")
+		logSys.debug("[%s] Flushed all journal matches", self.jailName)
 		match_copy = self.__matches[:]
 		self.__matches = []
 		try:
@@ -157,14 +158,17 @@ class FilterSystemd(JournalFilter): # pragma: systemd no cover
 	def delJournalMatch(self, match=None):
 		# clear all:
 		if match is None:
+			if not self.__matches:
+				return
 			del self.__matches[:]
 		# delete by index:
 		elif match in self.__matches:
 			del self.__matches[self.__matches.index(match)]
 		else:
-			raise ValueError("Match not found")
+			raise ValueError("Match %r not found" % match)
 		self.resetJournalMatches()
-		logSys.info("Removed journal match for: %r" % " ".join(match))
+		logSys.info("[%s] Removed journal match for: %r", self.jailName, 
+			match if match else '*')
 
 	##
 	# Get current journal match filter
@@ -214,8 +218,8 @@ class FilterSystemd(JournalFilter): # pragma: systemd no cover
 
 		date = logentry.get('_SOURCE_REALTIME_TIMESTAMP',
 				logentry.get('__REALTIME_TIMESTAMP'))
-		logSys.debug("Read systemd journal entry: %r" %
-			"".join([date.isoformat(), logline]))
+		logSys.debug("[%s] Read systemd journal entry: %s %s", self.jailName,
+			date.isoformat(), logline)
 		## use the same type for 1st argument:
 		return ((logline[:0], date.isoformat(), logline),
 			time.mktime(date.timetuple()) + date.microsecond/1.0E6)
@@ -302,6 +306,7 @@ class FilterSystemd(JournalFilter): # pragma: systemd no cover
 				# incr common error counter:
 				self.commonError()
 
+		logSys.debug("[%s] filter terminated", self.jailName)
 		# close journal:
 		try:
 			if self.__journal:
diff --git a/fail2ban/server/jail.py b/fail2ban/server/jail.py
index aa4a38cc..39fdd959 100644
--- a/fail2ban/server/jail.py
+++ b/fail2ban/server/jail.py
@@ -257,8 +257,7 @@ class Jail(object):
 					obj.stop()
 				## wait for end of threads:
 				if join:
-					if obj.isAlive():
-						obj.join()
+					obj.join()
 			except Exception as e:
 				logSys.error("Stop %r of jail %r failed: %s", obj, self.name, e,
 					exc_info=logSys.getEffectiveLevel()<=logging.DEBUG)
diff --git a/fail2ban/server/jailthread.py b/fail2ban/server/jailthread.py
index 39a86c2b..280b2171 100644
--- a/fail2ban/server/jailthread.py
+++ b/fail2ban/server/jailthread.py
@@ -53,8 +53,8 @@ class JailThread(Thread):
 		super(JailThread, self).__init__(name=name)
 		## Should going with main thread also:
 		self.daemon = True
-		## Control the state of the thread.
-		self.active = False
+		## Control the state of the thread (None - was not started, True - active, False - stopped).
+		self.active = None
 		## Control the idle state of the thread.
 		self.idle = False
 		## The time the thread sleeps in the loop.
@@ -93,3 +93,14 @@ class JailThread(Thread):
 		"""Abstract - Called when thread starts, thread stops when returns.
 		"""
 		pass
+
+	def join(self):
+		""" Safer join, that could be called also for not started (or ended) threads (used for cleanup).
+		"""
+		## if cleanup needed - create derivate and call it before join...
+
+		## if was really started - should call join:
+		if self.active is not None:
+			super(JailThread, self).join()
+
+
diff --git a/fail2ban/server/transmitter.py b/fail2ban/server/transmitter.py
index 19cf51ef..2f5be043 100644
--- a/fail2ban/server/transmitter.py
+++ b/fail2ban/server/transmitter.py
@@ -102,7 +102,7 @@ class Transmitter:
 					self.__commandHandler(cmd)
 			finally:
 				self.__server.reloadJails(*opts, begin=False)
-			return None
+			return 'OK'
 		elif len(command) >= 2 and command[0] == "unban":
 			# unban in all jails:
 			value = command[1:]