diff --git a/CHANGELOG.md b/CHANGELOG.md
index 93b51220..bca7c66b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -76,6 +76,7 @@ v1.6.0 - unreleased
 - Enhancement: Move Mailu Docker network to a fixed subnet ([#727](https://github.com/Mailu/Mailu/issues/727))
 - Enhancement: Added regex validation for alias username ([#764](https://github.com/Mailu/Mailu/issues/764))
 - Enhancement: Update documentation
+- Enhancement: Add logging at critical places in python start.py scripts. Implement LOG_LEVEL to controll verbosity ([#588](https://github.com/Mailu/Mailu/issues/588))
 - Upstream: Update Roundcube
 - Upstream: Update Rainloop
 - Bug: Rainloop fails with "domain not allowed" ([#93](https://github.com/Mailu/Mailu/issues/93))
diff --git a/core/dovecot/start.py b/core/dovecot/start.py
index 68043cd1..b4289b76 100755
--- a/core/dovecot/start.py
+++ b/core/dovecot/start.py
@@ -12,7 +12,7 @@ import sys
 from tenacity import retry
 from podop import run_server
 
-log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARN")
+log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARNING")
 
 def start_podop():
     os.setuid(8)
diff --git a/core/nginx/config.py b/core/nginx/config.py
index 719a6450..528a3247 100755
--- a/core/nginx/config.py
+++ b/core/nginx/config.py
@@ -7,7 +7,7 @@ import sys
 
 args = os.environ.copy()
 
-log.basicConfig(stream=sys.stderr, level=args["LOG_LEVEL"] if "LOG_LEVEL" in args else "WARN")
+log.basicConfig(stream=sys.stderr, level=args["LOG_LEVEL"] if "LOG_LEVEL" in args else "WARNING")
 
 def convert(src, dst, args):
     logger = log.getLogger("convert()")
diff --git a/core/postfix/start.py b/core/postfix/start.py
index 3214e077..5a8c2968 100755
--- a/core/postfix/start.py
+++ b/core/postfix/start.py
@@ -13,7 +13,7 @@ import sys
 from tenacity import retry
 from podop import run_server
 
-log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARN")
+log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARNING")
 
 def start_podop():
     os.setuid(100)
diff --git a/docs/compose/.env b/docs/compose/.env
index 836e9dbf..f65c2f01 100644
--- a/docs/compose/.env
+++ b/docs/compose/.env
@@ -151,3 +151,6 @@ REAL_IP_FROM=
 
 # choose wether mailu bounces (no) or rejects (yes) mail when recipient is unknown (value: yes, no)
 REJECT_UNLISTED_RECIPIENT=
+
+# Log level threshold in start.py (value: CRITICAL, ERROR, WARNING, INFO, DEBUG, NOTSET)
+LOG_LEVEL=WARNING
diff --git a/docs/configuration.rst b/docs/configuration.rst
index 2f44b293..ecb42fe5 100644
--- a/docs/configuration.rst
+++ b/docs/configuration.rst
@@ -83,6 +83,13 @@ The ``PASSWORD_SCHEME`` is the password encryption scheme. You should use the
 default value, unless you are importing password from a separate system and
 want to keep using the old password encryption scheme.
 
+The ``LOG_LEVEL`` setting is used by the python start-up scripts as a logging threshold.
+Log messages equal or higher than this priority will be printed.
+Can be one of: CRITICAL, ERROR, WARNING, INFO, DEBUG or NOTSET.
+See the `python docs`_ for more information.
+
+.. _`python docs`: https://docs.python.org/3.6/library/logging.html#logging-levels
+
 Infrastructure settings
 -----------------------
 
diff --git a/optional/clamav/start.py b/optional/clamav/start.py
index 19f91bcf..c08df509 100755
--- a/optional/clamav/start.py
+++ b/optional/clamav/start.py
@@ -4,7 +4,7 @@ import os
 import logging as log
 import sys
 
-log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARN")
+log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARNING")
 logger=log.getLogger(__name__)
 
 # Bootstrap the database if clamav is running for the first time
diff --git a/services/rspamd/start.py b/services/rspamd/start.py
index 8819407f..047bfeba 100755
--- a/services/rspamd/start.py
+++ b/services/rspamd/start.py
@@ -10,7 +10,7 @@ import sys
 
 from tenacity import retry
 
-log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARN")
+log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARNING")
 
 def convert(src, dst):
     logger = log.getLogger("convert()")
diff --git a/services/unbound/start.py b/services/unbound/start.py
index 198934c6..43a52df1 100755
--- a/services/unbound/start.py
+++ b/services/unbound/start.py
@@ -5,7 +5,7 @@ import os
 import logging as log
 import sys
 
-log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARN")
+log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARNING")
 
 def convert(src, dst):
     logger = log.getLogger("convert()")
diff --git a/setup/flavors/compose/mailu.env b/setup/flavors/compose/mailu.env
index 6bdc5e21..2d2b8735 100644
--- a/setup/flavors/compose/mailu.env
+++ b/setup/flavors/compose/mailu.env
@@ -160,3 +160,6 @@ REAL_IP_FROM={{ real_ip_from }}
 
 # choose wether mailu bounces (no) or rejects (yes) mail when recipient is unknown (value: yes, no)
 REJECT_UNLISTED_RECIPIENT={{ reject_unlisted_recipient }}
+
+# Log level threshold in start.py (value: CRITICAL, ERROR, WARNING, INFO, DEBUG, NOTSET)
+LOG_LEVEL=WARNING
diff --git a/webmails/rainloop/start.py b/webmails/rainloop/start.py
index 3b4ac3da..defc5be6 100755
--- a/webmails/rainloop/start.py
+++ b/webmails/rainloop/start.py
@@ -6,7 +6,7 @@ import shutil
 import logging as log
 import sys
 
-log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARN")
+log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARNING")
 
 def convert(src, dst):
     logger = log.getLogger("convert()")
diff --git a/webmails/roundcube/start.py b/webmails/roundcube/start.py
index ccb5faf5..8d48d3b6 100755
--- a/webmails/roundcube/start.py
+++ b/webmails/roundcube/start.py
@@ -5,7 +5,7 @@ import jinja2
 import logging as log
 import sys
 
-log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARN")
+log.basicConfig(stream=sys.stderr, level=os.environ["LOG_LEVEL"] if "LOG_LEVEL" in os.environ else "WARNING")
 
 def convert(src, dst):
     logger = log.getLogger("convert()")