diff --git a/web-apache-mysql/alpine/docker-entrypoint.sh b/web-apache-mysql/alpine/docker-entrypoint.sh
index 5051029e5..190c262c2 100755
--- a/web-apache-mysql/alpine/docker-entrypoint.sh
+++ b/web-apache-mysql/alpine/docker-entrypoint.sh
@@ -170,7 +170,7 @@ prepare_web_server() {
 prepare_zbx_web_config() {
     echo "** Preparing Zabbix frontend configuration file"
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -180,7 +180,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="MYSQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -193,15 +193,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -215,7 +215,7 @@ prepare_zbx_web_config() {
         rm -f "/tmp/defines.inc.php_tmp"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-apache-mysql/centos/docker-entrypoint.sh b/web-apache-mysql/centos/docker-entrypoint.sh
index 9f383f509..c6fbb1f7a 100755
--- a/web-apache-mysql/centos/docker-entrypoint.sh
+++ b/web-apache-mysql/centos/docker-entrypoint.sh
@@ -179,7 +179,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -189,7 +189,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="MYSQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -202,15 +202,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -224,7 +224,7 @@ prepare_zbx_web_config() {
         rm -f "/tmp/defines.inc.php_tmp"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-apache-mysql/ubuntu/docker-entrypoint.sh b/web-apache-mysql/ubuntu/docker-entrypoint.sh
index fb4742ed5..7dba1d3e0 100755
--- a/web-apache-mysql/ubuntu/docker-entrypoint.sh
+++ b/web-apache-mysql/ubuntu/docker-entrypoint.sh
@@ -170,7 +170,7 @@ prepare_web_server() {
 prepare_zbx_web_config() {
     echo "** Preparing Zabbix frontend configuration file"
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -180,7 +180,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="MYSQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -193,15 +193,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -215,7 +215,7 @@ prepare_zbx_web_config() {
         rm -f "/tmp/defines.inc.php_tmp"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-apache-pgsql/alpine/docker-entrypoint.sh b/web-apache-pgsql/alpine/docker-entrypoint.sh
index 7cee84593..a14be0286 100755
--- a/web-apache-pgsql/alpine/docker-entrypoint.sh
+++ b/web-apache-pgsql/alpine/docker-entrypoint.sh
@@ -154,7 +154,7 @@ prepare_web_server() {
 prepare_zbx_web_config() {
     echo "** Preparing Zabbix frontend configuration file"
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -164,7 +164,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="POSTGRESQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -177,15 +177,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
-
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -199,7 +199,7 @@ prepare_zbx_web_config() {
         rm -f "/tmp/defines.inc.php_tmp"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-apache-pgsql/centos/docker-entrypoint.sh b/web-apache-pgsql/centos/docker-entrypoint.sh
index 87cf18a5a..d15f0f322 100755
--- a/web-apache-pgsql/centos/docker-entrypoint.sh
+++ b/web-apache-pgsql/centos/docker-entrypoint.sh
@@ -163,7 +163,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -173,7 +173,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="POSTGRESQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -186,15 +186,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
-
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -208,7 +208,7 @@ prepare_zbx_web_config() {
         rm -f "/tmp/defines.inc.php_tmp"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-apache-pgsql/ubuntu/docker-entrypoint.sh b/web-apache-pgsql/ubuntu/docker-entrypoint.sh
index c20c4d59a..969d07913 100755
--- a/web-apache-pgsql/ubuntu/docker-entrypoint.sh
+++ b/web-apache-pgsql/ubuntu/docker-entrypoint.sh
@@ -158,7 +158,7 @@ clear_deploy() {
 prepare_zbx_web_config() {
     echo "** Preparing Zabbix frontend configuration file"
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -168,7 +168,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="POSTGRESQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -181,15 +181,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
-    export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,c}
+    : ${ZBX_DB_ENCRYPTION:="false"}
+    export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -203,7 +203,7 @@ prepare_zbx_web_config() {
         rm -f "/tmp/defines.inc.php_tmp"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-nginx-mysql/alpine/docker-entrypoint.sh b/web-nginx-mysql/alpine/docker-entrypoint.sh
index 40aeef4a0..b2f65e34d 100755
--- a/web-nginx-mysql/alpine/docker-entrypoint.sh
+++ b/web-nginx-mysql/alpine/docker-entrypoint.sh
@@ -180,7 +180,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -190,7 +190,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="MYSQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -203,15 +203,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -236,7 +236,7 @@ prepare_zbx_web_config() {
         "$ZABBIX_ETC_DIR/nginx_ssl.conf"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-nginx-mysql/centos/docker-entrypoint.sh b/web-nginx-mysql/centos/docker-entrypoint.sh
index 1e827d21c..f4587f6f9 100755
--- a/web-nginx-mysql/centos/docker-entrypoint.sh
+++ b/web-nginx-mysql/centos/docker-entrypoint.sh
@@ -180,7 +180,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -190,7 +190,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="MYSQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -203,15 +203,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -236,7 +236,7 @@ prepare_zbx_web_config() {
         "$ZABBIX_ETC_DIR/nginx_ssl.conf"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-nginx-mysql/ubuntu/docker-entrypoint.sh b/web-nginx-mysql/ubuntu/docker-entrypoint.sh
index c9f96dd80..81a0f57d7 100755
--- a/web-nginx-mysql/ubuntu/docker-entrypoint.sh
+++ b/web-nginx-mysql/ubuntu/docker-entrypoint.sh
@@ -180,7 +180,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -190,7 +190,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="MYSQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -203,15 +203,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -236,7 +236,7 @@ prepare_zbx_web_config() {
         "$ZABBIX_ETC_DIR/nginx_ssl.conf"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-nginx-pgsql/alpine/docker-entrypoint.sh b/web-nginx-pgsql/alpine/docker-entrypoint.sh
index c750f59e0..fec6b9b68 100755
--- a/web-nginx-pgsql/alpine/docker-entrypoint.sh
+++ b/web-nginx-pgsql/alpine/docker-entrypoint.sh
@@ -164,7 +164,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -174,7 +174,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="POSTGRESQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -187,15 +187,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -218,7 +218,7 @@ prepare_zbx_web_config() {
         "$ZABBIX_ETC_DIR/nginx_ssl.conf"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-nginx-pgsql/centos/docker-entrypoint.sh b/web-nginx-pgsql/centos/docker-entrypoint.sh
index 5232cd04d..fadeec6a8 100755
--- a/web-nginx-pgsql/centos/docker-entrypoint.sh
+++ b/web-nginx-pgsql/centos/docker-entrypoint.sh
@@ -164,7 +164,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -174,7 +174,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="POSTGRESQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -187,15 +187,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -218,7 +218,7 @@ prepare_zbx_web_config() {
         "$ZABBIX_ETC_DIR/nginx_ssl.conf"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \
diff --git a/web-nginx-pgsql/ubuntu/docker-entrypoint.sh b/web-nginx-pgsql/ubuntu/docker-entrypoint.sh
index b9bdf835c..df6c80c69 100755
--- a/web-nginx-pgsql/ubuntu/docker-entrypoint.sh
+++ b/web-nginx-pgsql/ubuntu/docker-entrypoint.sh
@@ -164,7 +164,7 @@ prepare_zbx_web_config() {
         echo "listen.group = nginx" >> "$PHP_CONFIG_FILE"
     fi
 
-    ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS:-"false"}
+    : ${ZBX_DENY_GUI_ACCESS:="false"}
     export ZBX_DENY_GUI_ACCESS=${ZBX_DENY_GUI_ACCESS,,}
     export ZBX_GUI_ACCESS_IP_RANGE=${ZBX_GUI_ACCESS_IP_RANGE:-"['127.0.0.1']"}
     export ZBX_GUI_WARNING_MSG=${ZBX_GUI_WARNING_MSG:-"Zabbix is under maintenance."}
@@ -174,7 +174,7 @@ prepare_zbx_web_config() {
     export ZBX_POSTMAXSIZE=${ZBX_POSTMAXSIZE:-"16M"}
     export ZBX_UPLOADMAXFILESIZE=${ZBX_UPLOADMAXFILESIZE:-"2M"}
     export ZBX_MAXINPUTTIME=${ZBX_MAXINPUTTIME:-"300"}
-    export PHP_TZ=${PHP_TZ:-"Europe/Riga"}
+    export PHP_TZ=${PHP_TZ}
 
     export DB_SERVER_TYPE="POSTGRESQL"
     export DB_SERVER_HOST=${DB_SERVER_HOST}
@@ -187,15 +187,15 @@ prepare_zbx_web_config() {
     export ZBX_SERVER_PORT=${ZBX_SERVER_PORT:-"10051"}
     export ZBX_SERVER_NAME=${ZBX_SERVER_NAME}
 
-    ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION:-"false"}
+    : ${ZBX_DB_ENCRYPTION:="false"}
     export ZBX_DB_ENCRYPTION=${ZBX_DB_ENCRYPTION,,}
     export ZBX_DB_KEY_FILE=${ZBX_DB_KEY_FILE}
     export ZBX_DB_CERT_FILE=${ZBX_DB_CERT_FILE}
     export ZBX_DB_CA_FILE=${ZBX_DB_CA_FILE}
-    ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST:-"false"}
+    : ${ZBX_DB_VERIFY_HOST:="false"}
     export ZBX_DB_VERIFY_HOST=${ZBX_DB_VERIFY_HOST,,}
 
-    DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754:-"true"}
+    : ${DB_DOUBLE_IEEE754:="true"}
     export DB_DOUBLE_IEEE754=${DB_DOUBLE_IEEE754,,}
 
     export ZBX_HISTORYSTORAGEURL=${ZBX_HISTORYSTORAGEURL}
@@ -218,7 +218,7 @@ prepare_zbx_web_config() {
         "$ZABBIX_ETC_DIR/nginx_ssl.conf"
     fi
 
-    ENABLE_WEB_ACCESS_LOG=${ENABLE_WEB_ACCESS_LOG:-"true"}
+    : ${ENABLE_WEB_ACCESS_LOG:="true"}
 
     if [ "${ENABLE_WEB_ACCESS_LOG,,}" == "false" ]; then
         sed -ri \