diff --git a/3.3/Dockerfile b/3.3/Dockerfile
index b37a6ed9..87cf3d64 100644
--- a/3.3/Dockerfile
+++ b/3.3/Dockerfile
@@ -32,7 +32,14 @@ RUN set -eux; \
 	wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \
 	wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \
 	export GNUPGHOME="$(mktemp -d)"; \
-	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
+	# from https://github.com/tianon/gosu/issues/35#issuecomment-299205512 to avoid intermittent issues with some keyservers
+	for server in $(shuf -e ha.pool.sks-keyservers.net \
+				hkp://p80.pool.sks-keyservers.net:80 \
+				keyserver.ubuntu.com \
+				hkp://keyserver.ubuntu.com:80 \
+				pgp.mit.edu) ; do \
+		gpg --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
+	done; \
 	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
 	gpgconf --kill all; \
 	rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc; \
diff --git a/3.3/docker-entrypoint.sh b/3.3/docker-entrypoint.sh
index e0a4ff5a..db2543af 100755
--- a/3.3/docker-entrypoint.sh
+++ b/3.3/docker-entrypoint.sh
@@ -127,11 +127,15 @@ case "$1" in
 		if [ "$1" != 'rake' -a -z "$REDMINE_NO_DB_MIGRATE" ]; then
 			gosu redmine rake db:migrate
 		fi
+
+		file_env 'REDMINE_NO_CHOWN' ''
 		
-		# https://www.redmine.org/projects/redmine/wiki/RedmineInstall#Step-8-File-system-permissions
-		chown -R redmine:redmine files log public/plugin_assets
-		# directories 755, files 644:
-		chmod -R ugo-x,u+rwX,go+rX,go-w files log tmp public/plugin_assets
+		if [ "$REDMINE_NO_CHOWN" == "" ]; then
+			# https://www.redmine.org/projects/redmine/wiki/RedmineInstall#Step-8-File-system-permissions
+			chown -R redmine:redmine files log public/plugin_assets
+			# directories 755, files 644:
+			chmod -R ugo-x,u+rwX,go+rX,go-w files log tmp public/plugin_assets
+		fi
 		
 		if [ "$1" != 'rake' -a -n "$REDMINE_PLUGINS_MIGRATE" ]; then
 			gosu redmine rake redmine:plugins:migrate
diff --git a/3.3/passenger/Dockerfile b/3.3/passenger/Dockerfile
index 3ac5e12d..7bd8c8c2 100644
--- a/3.3/passenger/Dockerfile
+++ b/3.3/passenger/Dockerfile
@@ -1,6 +1,6 @@
 FROM redmine:3.3
 
-ENV PASSENGER_VERSION 5.3.2
+ENV PASSENGER_VERSION 5.3.3
 
 RUN buildDeps=' \
 		make \
diff --git a/3.4/Dockerfile b/3.4/Dockerfile
index 270921be..c84ae84f 100644
--- a/3.4/Dockerfile
+++ b/3.4/Dockerfile
@@ -32,7 +32,14 @@ RUN set -eux; \
 	wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \
 	wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \
 	export GNUPGHOME="$(mktemp -d)"; \
-	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
+	# from https://github.com/tianon/gosu/issues/35#issuecomment-299205512 to avoid intermittent issues with some keyservers
+	for server in $(shuf -e ha.pool.sks-keyservers.net \
+				hkp://p80.pool.sks-keyservers.net:80 \
+				keyserver.ubuntu.com \
+				hkp://keyserver.ubuntu.com:80 \
+				pgp.mit.edu) ; do \
+		gpg --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
+	done; \
 	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
 	gpgconf --kill all; \
 	rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc; \
diff --git a/3.4/docker-entrypoint.sh b/3.4/docker-entrypoint.sh
index e0a4ff5a..db2543af 100755
--- a/3.4/docker-entrypoint.sh
+++ b/3.4/docker-entrypoint.sh
@@ -127,11 +127,15 @@ case "$1" in
 		if [ "$1" != 'rake' -a -z "$REDMINE_NO_DB_MIGRATE" ]; then
 			gosu redmine rake db:migrate
 		fi
+
+		file_env 'REDMINE_NO_CHOWN' ''
 		
-		# https://www.redmine.org/projects/redmine/wiki/RedmineInstall#Step-8-File-system-permissions
-		chown -R redmine:redmine files log public/plugin_assets
-		# directories 755, files 644:
-		chmod -R ugo-x,u+rwX,go+rX,go-w files log tmp public/plugin_assets
+		if [ "$REDMINE_NO_CHOWN" == "" ]; then
+			# https://www.redmine.org/projects/redmine/wiki/RedmineInstall#Step-8-File-system-permissions
+			chown -R redmine:redmine files log public/plugin_assets
+			# directories 755, files 644:
+			chmod -R ugo-x,u+rwX,go+rX,go-w files log tmp public/plugin_assets
+		fi
 		
 		if [ "$1" != 'rake' -a -n "$REDMINE_PLUGINS_MIGRATE" ]; then
 			gosu redmine rake redmine:plugins:migrate
diff --git a/3.4/passenger/Dockerfile b/3.4/passenger/Dockerfile
index c968995c..c905c7cc 100644
--- a/3.4/passenger/Dockerfile
+++ b/3.4/passenger/Dockerfile
@@ -1,6 +1,6 @@
 FROM redmine:3.4
 
-ENV PASSENGER_VERSION 5.3.2
+ENV PASSENGER_VERSION 5.3.3
 
 RUN buildDeps=' \
 		make \
diff --git a/Dockerfile.template b/Dockerfile.template
index 45c29e95..e8d2ac2b 100644
--- a/Dockerfile.template
+++ b/Dockerfile.template
@@ -32,7 +32,14 @@ RUN set -eux; \
 	wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch"; \
 	wget -O /usr/local/bin/gosu.asc "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch.asc"; \
 	export GNUPGHOME="$(mktemp -d)"; \
-	gpg --keyserver ha.pool.sks-keyservers.net --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4; \
+	# from https://github.com/tianon/gosu/issues/35#issuecomment-299205512 to avoid intermittent issues with some keyservers
+	for server in $(shuf -e ha.pool.sks-keyservers.net \
+				hkp://p80.pool.sks-keyservers.net:80 \
+				keyserver.ubuntu.com \
+				hkp://keyserver.ubuntu.com:80 \
+				pgp.mit.edu) ; do \
+		gpg --keyserver "$server" --recv-keys B42F6819007F00F88E364FD4036A9C25BF357DD4 && break || : ; \
+	done; \
 	gpg --batch --verify /usr/local/bin/gosu.asc /usr/local/bin/gosu; \
 	gpgconf --kill all; \
 	rm -r "$GNUPGHOME" /usr/local/bin/gosu.asc; \
diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index e0a4ff5a..db2543af 100755
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -127,11 +127,15 @@ case "$1" in
 		if [ "$1" != 'rake' -a -z "$REDMINE_NO_DB_MIGRATE" ]; then
 			gosu redmine rake db:migrate
 		fi
+
+		file_env 'REDMINE_NO_CHOWN' ''
 		
-		# https://www.redmine.org/projects/redmine/wiki/RedmineInstall#Step-8-File-system-permissions
-		chown -R redmine:redmine files log public/plugin_assets
-		# directories 755, files 644:
-		chmod -R ugo-x,u+rwX,go+rX,go-w files log tmp public/plugin_assets
+		if [ "$REDMINE_NO_CHOWN" == "" ]; then
+			# https://www.redmine.org/projects/redmine/wiki/RedmineInstall#Step-8-File-system-permissions
+			chown -R redmine:redmine files log public/plugin_assets
+			# directories 755, files 644:
+			chmod -R ugo-x,u+rwX,go+rX,go-w files log tmp public/plugin_assets
+		fi
 		
 		if [ "$1" != 'rake' -a -n "$REDMINE_PLUGINS_MIGRATE" ]; then
 			gosu redmine rake redmine:plugins:migrate