diff --git a/README.md b/README.md
index 6a1bf68..c7180f2 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,7 @@ Monitorix is a free, open source, lightweight system monitoring tool designed to
 It has been created to be used under production Linux/UNIX servers, but due to its simplicity and small size can be used on embedded devices as well.
 
 
-**Shipped version:** 3.15.0~ynh5
+**Shipped version:** 3.15.0~ynh6
 
 **Demo:** <https://www.fibranet.cat/monitorix/>
 
diff --git a/README_eu.md b/README_eu.md
index b6603cd..004ac02 100644
--- a/README_eu.md
+++ b/README_eu.md
@@ -21,7 +21,7 @@ Monitorix is a free, open source, lightweight system monitoring tool designed to
 It has been created to be used under production Linux/UNIX servers, but due to its simplicity and small size can be used on embedded devices as well.
 
 
-**Paketatutako bertsioa:** 3.15.0~ynh5
+**Paketatutako bertsioa:** 3.15.0~ynh6
 
 **Demoa:** <https://www.fibranet.cat/monitorix/>
 
diff --git a/README_fr.md b/README_fr.md
index 3f44dda..8fc807f 100644
--- a/README_fr.md
+++ b/README_fr.md
@@ -21,7 +21,7 @@ Monitorix is a free, open source, lightweight system monitoring tool designed to
 It has been created to be used under production Linux/UNIX servers, but due to its simplicity and small size can be used on embedded devices as well.
 
 
-**Version incluse :** 3.15.0~ynh5
+**Version incluse :** 3.15.0~ynh6
 
 **Démo :** <https://www.fibranet.cat/monitorix/>
 
diff --git a/README_gl.md b/README_gl.md
index 12232c7..eed5ef4 100644
--- a/README_gl.md
+++ b/README_gl.md
@@ -21,7 +21,7 @@ Monitorix is a free, open source, lightweight system monitoring tool designed to
 It has been created to be used under production Linux/UNIX servers, but due to its simplicity and small size can be used on embedded devices as well.
 
 
-**Versión proporcionada:** 3.15.0~ynh5
+**Versión proporcionada:** 3.15.0~ynh6
 
 **Demo:** <https://www.fibranet.cat/monitorix/>
 
diff --git a/README_zh_Hans.md b/README_zh_Hans.md
index 0ffd21a..7aa9f4f 100644
--- a/README_zh_Hans.md
+++ b/README_zh_Hans.md
@@ -21,7 +21,7 @@ Monitorix is a free, open source, lightweight system monitoring tool designed to
 It has been created to be used under production Linux/UNIX servers, but due to its simplicity and small size can be used on embedded devices as well.
 
 
-**分发版本：** 3.15.0~ynh5
+**分发版本：** 3.15.0~ynh6
 
 **演示：** <https://www.fibranet.cat/monitorix/>
 
diff --git a/conf/monitorix-alert.sh b/conf/monitorix-alert.sh
index 2544ecf..cacb65f 100644
--- a/conf/monitorix-alert.sh
+++ b/conf/monitorix-alert.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 #
 # Example script used to execute an alert action.
 #
diff --git a/conf/systemd.service b/conf/systemd.service
index 97d619c..310c2aa 100644
--- a/conf/systemd.service
+++ b/conf/systemd.service
@@ -27,7 +27,7 @@ ProtectKernelModules=yes
 ProtectKernelTunables=yes
 LockPersonality=yes
 SystemCallArchitectures=native
-SystemCallFilter=~@clock @debug @module @mount @obsolete @reboot @cpu-emulation @swap
+SystemCallFilter=~@clock @debug @module @obsolete @reboot @cpu-emulation @swap
 
 # # Denying access to capabilities that should not be relevant for webapps
 # # Doc: https://man7.org/linux/man-pages/man7/capabilities.7.html
diff --git a/manifest.toml b/manifest.toml
index e1ede2c..b3467d3 100644
--- a/manifest.toml
+++ b/manifest.toml
@@ -7,7 +7,7 @@ name = "Monitorix"
 description.en = "A system monitoring tool"
 description.fr = "Un outil de monitoring système"
 
-version = "3.15.0~ynh5"
+version = "3.15.0~ynh6"
 
 maintainers = ["Josué Tille"]
 
@@ -20,7 +20,7 @@ code = "https://github.com/mikaku/Monitorix"
 cpe = "cpe:2.3:a:fibranet:monitorix"
 
 [integration]
-yunohost = ">= 11.0.11"
+yunohost = ">= 11.2.11"
 architectures = "all"
 multi_instance = false
 ldap = "not_relevant"
diff --git a/scripts/_common.sh b/scripts/_common.sh
index fcf8c2e..e59c7f7 100644
--- a/scripts/_common.sh
+++ b/scripts/_common.sh
@@ -79,7 +79,7 @@ load_vars() {
     readonly home_user_dirs="$(echo /home/* | home_dir_filter)"
     readonly net_gateway="$(ip --json route show default | jq -r '.[0].dev')"
     readonly net_interface_list="$(ip --json link show | jq -r '.[].ifname | select(. != "lo")' | interface_speed_map)"
-    readonly net_max_speed="$(cat /sys/class/net/*/speed  2>/dev/null | sort | tail -n1)"
+    readonly net_max_speed="$(cat /sys/class/net/*/speed  2>/dev/null | sort | tail -n1 | sed 's|-1|1000|g')"
     readonly ssh_port="$((grep ssh_port /etc/yunohost/settings.yml || echo 22) | cut -d: -f2 | xargs)"
     readonly port_infos="$(python3 <<EOF
 import yaml, socket
@@ -96,6 +96,8 @@ with open("/etc/yunohost/firewall.yml", "r") as f:
                       if str(port) not in hard_coded_ports]
 with open("/etc/yunohost/services.yml", "r") as f:
     services = yaml.safe_load(f)
+    if services is None:
+        services = dict()
     port_map = dict()
     for key, value in services.items():
         if 'needs_exposed_ports' in value:
@@ -125,6 +127,8 @@ import yaml, socket
 hard_coded_ports = ["25", "53", "80", "443", "587", "993"]
 with open("/etc/yunohost/services.yml", "r") as f:
     services = yaml.safe_load(f)
+    if services is None:
+        services = dict()
     results = ["%s|%s" % (k, v["description"] if "description" in v else k) for k, v in services.items()]
     print('\n'.join(results))
 EOF
@@ -145,7 +149,7 @@ EOF
 # Used by update_config_if_needed.sh hook
 save_vars_current_value() {
     for var in $var_list_to_manage; do
-        ynh_app_setting_set --app "$app" --key previous_$var --value "${!var}"
+        ynh_app_setting_set --app="$app" --key="previous_$var" --value="${!var}"
     done
 }
 
diff --git a/scripts/backup b/scripts/backup
index ce158a9..d48d15c 100755
--- a/scripts/backup
+++ b/scripts/backup
@@ -15,7 +15,7 @@ load_vars
 #=================================================
 # STOP SYSTEMD SERVICE
 #=================================================
-if systemctl is-active $app.service --quiet; then
+if systemctl is-active "$app".service --quiet; then
     ynh_print_warn --message="It's highly recommended to make your backup when the service is stopped. Please stop $app service with this command before to run the backup 'systemctl stop $app.service'"
 fi
 
@@ -29,11 +29,11 @@ ynh_print_info --message="Declaring files to be backed up..."
 #=================================================
 
 ynh_backup --src_path="/etc/$app/"
-ynh_backup --src_path "/etc/nginx/conf.d/$domain.d/$app.conf"
-ynh_backup --src_path "$nginx_status_conf"
+ynh_backup --src_path="/etc/nginx/conf.d/$domain.d/$app.conf"
+ynh_backup --src_path="$nginx_status_conf"
 
 ynh_print_info --message="Backing up code..."
-ynh_backup --src_path $install_dir
+ynh_backup --src_path="$install_dir"
 
 #=================================================
 # SPECIFIC BACKUP
@@ -41,7 +41,7 @@ ynh_backup --src_path $install_dir
 # BACKUP SYSTEMD
 #=================================================
 
-ynh_backup --src_path "/etc/systemd/system/$app.service"
+ynh_backup --src_path="/etc/systemd/system/$app.service"
 
 #=================================================
 # BACKUP VARIOUS FILES
diff --git a/scripts/change_url b/scripts/change_url
index 1775302..5048134 100644
--- a/scripts/change_url
+++ b/scripts/change_url
@@ -18,7 +18,7 @@ load_vars
 #=================================================
 ynh_script_progression --message="Stopping a systemd service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action="stop" --log_path="/var/log/$app/$app.log"
+ynh_systemd_action --service_name="$app" --action="stop" --log_path="/var/log/$app/$app.log"
 
 #=================================================
 # MODIFY URL IN NGINX CONF
@@ -39,7 +39,7 @@ ynh_add_jinja_config --template=monitorix.conf --destination=/etc/monitorix/moni
 # START SYSTEMD SERVICE
 #=================================================
 ynh_script_progression --message="Starting a systemd service..." --weight=1
-ynh_systemd_action --service_name="$app" --action=start --log_path 'systemd' --line_match ' - Ok, ready.'
+ynh_systemd_action --service_name="$app" --action=start --log_path='systemd' --line_match=' - Ok, ready.'
 
 #=================================================
 # END OF SCRIPT
diff --git a/scripts/experimental_helper.sh b/scripts/experimental_helper.sh
index 107ac88..bfdd78d 100644
--- a/scripts/experimental_helper.sh
+++ b/scripts/experimental_helper.sh
@@ -133,30 +133,3 @@ ynh_add_jinja_config() {
     )
     ynh_store_file_checksum --file="$destination"
 }
-
-# Check either a package is installed or not
-#
-# example: ynh_package_is_installed --package=yunohost && echo "installed"
-#
-# usage: ynh_package_is_installed --package=name [--wait_dpkg_free]
-# | arg: -p, --package=          - the package name to check
-# | arg: -l, --wait_dpkg_free=   - wait for dpkg to be free.
-# |                                Note that waiting on dpkg free could take about 0.2s on quick platform
-# |                                and about 2 seconds on slow platform so in case of multiple call it could be slow
-# | ret: 0 if the package is installed, 1 else.
-ynh_package_is_installed() {
-    # Declare an array to define the options of this helper.
-    local legacy_args=pl
-    local -A args_array=([p]=package= [l]=wait_dpkg_free=)
-    local package
-    local wait_dpkg_free
-    # Manage arguments with getopts
-    ynh_handle_getopts_args "$@"
-    wait_dpkg_free="${wait_dpkg_free:-0}"
-
-    if [ "$wait_dpkg_free" -eq 1 ]; then
-        ynh_wait_dpkg_free
-    fi
-    dpkg-query --show --showformat='${Status}' "$package" 2>/dev/null \
-        | grep --count "ok installed" &>/dev/null
-}
diff --git a/scripts/install b/scripts/install
index b7eb8a4..603c236 100755
--- a/scripts/install
+++ b/scripts/install
@@ -17,34 +17,25 @@ ensure_vars_set
 # Check datadir empty
 #=================================================
 
-if [ -n "$(ls -A $data_dir)" ]; then
+if [ -n "$(ls -A "$data_dir")" ]; then
     old_data_dir_path="${data_dir}_$(date '+%Y%m%d.%H%M%S')"
     ynh_print_warn --message="Data directory was not empty. Data was moved to $old_data_dir_path"
-    mkdir -p $old_data_dir_path
+    mkdir -p "$old_data_dir_path"
     mv -t "$old_data_dir_path" "$data_dir"/*
     app_data_dirs="$(echo /home/yunohost.app/*)"
 fi
-
-#=================================================
-# STANDARD MODIFICATIONS
-#=================================================
-ynh_script_progression --message="Installing packages..." --weight=1
-
-# Download package and install it
-install_monitorix_package
+mkdir -p /var/log/"$app"
 
 ynh_systemd_action --service_name="$app" --action=stop --log_path=systemd --timeout=15
-mkdir -p /var/log/new_"${app}"
-mv -t /var/log/new_"${app}" /var/log/monitorix*
-mv /var/log/new_"${app}" /var/log/"${app}"
 
 #=================================================
 # SYSTEM CONFIGURATION
 #=================================================ç
 ynh_script_progression --message="Adding configurations related to $app..." --weight=1
 
+mkdir -p /etc/monitorix
 ynh_add_jinja_config --template=monitorix.conf --destination="/etc/monitorix/monitorix.conf"
-ynh_add_jinja_config --template=nginx_status.conf --destination "$nginx_status_conf"
+ynh_add_jinja_config --template=nginx_status.conf --destination="$nginx_status_conf"
 
 ynh_add_nginx_config
 ynh_add_systemd_config
@@ -62,6 +53,14 @@ fi
 configure_hooks
 configure_alerts_email
 
+#=================================================
+# STANDARD MODIFICATIONS
+#=================================================
+ynh_script_progression --message="Installing packages..." --weight=1
+
+# Download package and install it
+install_monitorix_package
+
 #=================================================
 # GENERIC FINALIZATION
 #=================================================
@@ -69,14 +68,14 @@ ynh_script_progression --message="Protecting directory..."
 
 set_permission
 
-ynh_use_logrotate --logfile "/var/log/$app"
+ynh_use_logrotate --logfile="/var/log/$app"
 
 #=================================================
 # START SYSTEMD SERVICE
 #=================================================
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
-ynh_systemd_action --service_name="$app" --action="start" --log_path 'systemd' --line_match ' - Ok, ready.'
+ynh_systemd_action --service_name="$app" --action="start" --log_path='systemd' --line_match=' - Ok, ready.'
 # when we change the value of 'listen [::1]:xxx;' nginx don't reload correctly the config, so force to restart to ensure that the new config are loaded
 ynh_systemd_action --service_name=nginx.service --action=restart
 save_vars_current_value
diff --git a/scripts/remove b/scripts/remove
index 86f5fa6..bd84296 100755
--- a/scripts/remove
+++ b/scripts/remove
@@ -18,7 +18,7 @@ load_vars
 #=================================================
 
 # Remove the service from the list of services known by YunoHost (added from `yunohost service add`)
-if ynh_exec_warn_less yunohost service status $app >/dev/null
+if ynh_exec_warn_less yunohost service status "$app" >/dev/null
 then
     ynh_script_progression --message="Removing $app service integration..." --weight=3
     yunohost service remove "$app"
@@ -48,15 +48,18 @@ for pool_dir_by_version in /etc/php/*; do
     fi
 done
 
-if ynh_psql_user_exists --user=$db_user; then
-    ynh_psql_drop_user $db_user
+if ynh_psql_user_exists --user="$db_user"; then
+    ynh_psql_drop_user "$db_user"
 fi
-if ynh_mysql_user_exists --user=$db_user; then
-    ynh_mysql_drop_user $db_user
+if ynh_mysql_user_exists --user="$db_user"; then
+    ynh_mysql_drop_user "$db_user"
 fi
 
 ynh_package_autopurge monitorix
-ynh_secure_remove --file=/var/log/"$app"
 ynh_secure_remove --file="$install_dir"
 
+if [ "$YNH_APP_PURGE" -eq 1 ]; then
+    ynh_secure_remove --file=/var/log/"$app"
+fi
+
 ynh_script_progression --message="Removal of $app completed" --last
diff --git a/scripts/restore b/scripts/restore
index 23e5795..69a1eb8 100755
--- a/scripts/restore
+++ b/scripts/restore
@@ -12,17 +12,6 @@ source ../settings/scripts/experimental_helper.sh
 source /usr/share/yunohost/helpers
 load_vars
 
-#=================================================
-# RESTORE THE DEPENDENCIES
-#=================================================
-ynh_script_progression --message="Restoring the dependencies..." --weight=1
-
-install_monitorix_package
-ynh_systemd_action --service_name="$app" --action=stop --log_path=systemd --timeout=15
-mkdir -p /var/log/new_"${app}"
-mv -t /var/log/new_"${app}" /var/log/monitorix*
-mv /var/log/new_"${app}" /var/log/"${app}"
-
 ynh_script_progression --message="Configuring databases access..."
 configure_db
 
@@ -32,15 +21,23 @@ configure_db
 ynh_script_progression --message="Restoring files" --weight=1
 
 ynh_restore
-mkdir -p /var/log/$app
-systemctl enable $app.service --quiet
+mkdir -p /var/log/"$app"
+systemctl enable "$app".service --quiet
 
 ynh_script_progression --message="Configuring php fpm access if needed..."
 if "$phpfpm_installed"; then
     config_php_fpm
 fi
 
-yunohost service add $app --description="Monitorix" --log="systemd"
+yunohost service add "$app" --description="Monitorix" --log="systemd"
+
+#=================================================
+# RESTORE THE DEPENDENCIES
+#=================================================
+ynh_script_progression --message="Restoring the dependencies..." --weight=1
+
+install_monitorix_package
+ynh_systemd_action --service_name="$app" --action=stop --log_path=systemd --timeout=15
 
 #=================================================
 # GENERIC FINALIZATION
@@ -49,7 +46,7 @@ ynh_script_progression --message="Protecting directory..."
 
 set_permission
 
-ynh_use_logrotate --logfile "/var/log/$app"
+ynh_use_logrotate --logfile="/var/log/$app"
 
 #=================================================
 # GENERIC FINALIZATION
@@ -58,7 +55,7 @@ ynh_use_logrotate --logfile "/var/log/$app"
 #=================================================
 ynh_script_progression --message="Reloading NGINX web server and $app's service..." --weight=1
 
-ynh_systemd_action --service_name="$app" --action=start --log_path 'systemd' --line_match ' - Ok, ready.'
+ynh_systemd_action --service_name="$app" --action=start --log_path='systemd' --line_match=' - Ok, ready.'
 # when we change the value of 'listen [::1]:xxx;' nginx don't reload correctly the config, so force to restart to ensure that the new config are loaded
 ynh_systemd_action --service_name=nginx.service --action=restart
 ynh_systemd_action --service_name=nginx --action=reload
diff --git a/scripts/upgrade b/scripts/upgrade
index 164baa1..5984372 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -11,7 +11,7 @@ source experimental_helper.sh
 source /usr/share/yunohost/helpers
 load_vars
 
-upgrade_type=$(ynh_check_app_version_changed)
+upgrade_type="$(ynh_check_app_version_changed)"
 
 #=================================================
 # STANDARD UPGRADE STEPS
@@ -30,14 +30,14 @@ ynh_script_progression --message="Ensuring downward compatibility..." --weight=1
 test -e /etc/monitorix/conf.d/00-debian.conf || touch /etc/monitorix/conf.d/00-debian.conf
 
 # Remove old hook if exist
-ynh_secure_remove --file=/usr/share/yunohost/hooks/post_iptable_rules/50-$app
+ynh_secure_remove --file=/usr/share/yunohost/hooks/post_iptable_rules/50-"$app"
 
 #=================================================
 # STOP SYSTEMD SERVICE
 #=================================================
 ynh_script_progression --message="Stopping a systemd service..." --weight=1
 
-ynh_systemd_action --service_name=$app --action=stop --log_path="/var/log/$app/$app.log"
+ynh_systemd_action --service_name="$app" --action=stop --log_path="/var/log/$app/$app.log"
 
 #=================================================
 # "REBUILD" THE APP (DEPLOY NEW SOURCES, RERUN NPM BUILD...)
@@ -77,7 +77,7 @@ fi
 ynh_script_progression --message="Upgrading configurations related to $app..." --weight=1
 
 ynh_add_jinja_config --template=monitorix.conf --destination=/etc/monitorix/monitorix.conf
-ynh_add_jinja_config --template=nginx_status.conf --destination "$nginx_status_conf"
+ynh_add_jinja_config --template=nginx_status.conf --destination="$nginx_status_conf"
 if "$phpfpm_installed"; then
     config_php_fpm
 fi
@@ -104,14 +104,14 @@ ynh_script_progression --message="Protecting directory..."
 
 set_permission
 
-ynh_use_logrotate --logfile "/var/log/$app"
+ynh_use_logrotate --logfile="/var/log/$app"
 
 #=================================================
 # START SYSTEMD SERVICE
 #=================================================
 ynh_script_progression --message="Starting a systemd service..." --weight=1
 
-ynh_systemd_action --service_name="$app" --action=restart --log_path=systemd --line_match ' - Ok, ready.'
+ynh_systemd_action --service_name="$app" --action=restart --log_path=systemd --line_match=' - Ok, ready.'
 # when we change the value of 'listen [::1]:xxx;' nginx don't reload correctly the config, so force to restart to ensure that the new config are loaded
 ynh_systemd_action --service_name=nginx.service --action=restart
 save_vars_current_value
diff --git a/sources/update_config_if_needed.sh b/sources/update_config_if_needed.sh
index 8429664..a4846d3 100644
--- a/sources/update_config_if_needed.sh
+++ b/sources/update_config_if_needed.sh
@@ -76,13 +76,13 @@ if "$status_dirty"; then
     emailreports_yearly_to="$(ynh_app_setting_get --app="$app" --key=emailreports_yearly_to)"
 
     ynh_add_jinja_config --template=monitorix.conf --destination="/etc/monitorix/monitorix.conf"
-    ynh_add_jinja_config --template=nginx_status.conf --destination "$nginx_status_conf"
+    ynh_add_jinja_config --template=nginx_status.conf --destination="$nginx_status_conf"
     configure_db
 
     if "$phpfpm_installed"; then
         config_php_fpm
     fi
-    ynh_systemd_action --service_name="$app" --action=restart --log_path 'systemd' --line_match ' - Ok, ready.'
+    ynh_systemd_action --service_name="$app" --action=restart --log_path='systemd' --line_match=' - Ok, ready.'
     ynh_systemd_action --service_name=nginx --action=reload
     save_vars_current_value
 fi