diff --git a/docker/base/start.sh b/docker/base/start.sh
index b45660bd8f..2612912686 100644
--- a/docker/base/start.sh
+++ b/docker/base/start.sh
@@ -17,7 +17,7 @@ ARGS=""
 
 if [[ ! "${!KOLLA_SKIP_EXTEND_START[@]}" ]]; then
     # Run additional commands if present
-    source kolla_extend_start
+    . kolla_extend_start
 fi
 
 echo "Running command: '${CMD}${ARGS:+ $ARGS}'"
diff --git a/docker/ceilometer/ceilometer-base/extend_start.sh b/docker/ceilometer/ceilometer-base/extend_start.sh
index 19521d9def..b6027cf6d2 100644
--- a/docker/ceilometer/ceilometer-base/extend_start.sh
+++ b/docker/ceilometer/ceilometer-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/ceilometer) != "755" ]]; then
     chmod 755 /var/log/kolla/ceilometer
 fi
 
-source /usr/local/bin/kolla_ceilometer_extend_start
+. /usr/local/bin/kolla_ceilometer_extend_start
diff --git a/docker/cinder/cinder-base/extend_start.sh b/docker/cinder/cinder-base/extend_start.sh
index 6c655da29b..21fae59364 100644
--- a/docker/cinder/cinder-base/extend_start.sh
+++ b/docker/cinder/cinder-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/cinder) != "755" ]]; then
     chmod 755 /var/log/kolla/cinder
 fi
 
-source /usr/local/bin/kolla_cinder_extend_start
+. /usr/local/bin/kolla_cinder_extend_start
diff --git a/docker/designate/designate-base/extend_start.sh b/docker/designate/designate-base/extend_start.sh
index 92f091139d..66b376c301 100644
--- a/docker/designate/designate-base/extend_start.sh
+++ b/docker/designate/designate-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/designate) != "755" ]]; then
     chmod 755 /var/log/kolla/designate
 fi
 
-source /usr/local/bin/kolla_designate_extend_start
+. /usr/local/bin/kolla_designate_extend_start
diff --git a/docker/glance/glance-base/extend_start.sh b/docker/glance/glance-base/extend_start.sh
index e8a60bf648..4f5f5ecafa 100644
--- a/docker/glance/glance-base/extend_start.sh
+++ b/docker/glance/glance-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/glance) != "755" ]]; then
     chmod 755 /var/log/kolla/glance
 fi
 
-source /usr/local/bin/kolla_glance_extend_start
+. /usr/local/bin/kolla_glance_extend_start
diff --git a/docker/heat/heat-base/extend_start.sh b/docker/heat/heat-base/extend_start.sh
index de43a519cf..a73f17345f 100644
--- a/docker/heat/heat-base/extend_start.sh
+++ b/docker/heat/heat-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/heat) != "755" ]]; then
     chmod 755 /var/log/kolla/heat
 fi
 
-source /usr/local/bin/kolla_heat_extend_start
+. /usr/local/bin/kolla_heat_extend_start
diff --git a/docker/horizon/extend_start.sh b/docker/horizon/extend_start.sh
index d9c5fafd69..a34d33f52f 100644
--- a/docker/horizon/extend_start.sh
+++ b/docker/horizon/extend_start.sh
@@ -4,7 +4,7 @@
 # results in the container not being able to restart. (bug #1489676, 1557036)
 if [[ "${KOLLA_BASE_DISTRO}" =~ debian|ubuntu ]]; then
     # Loading Apache2 ENV variables
-    source /etc/apache2/envvars
+    . /etc/apache2/envvars
     rm -rf /var/run/apache2/*
 else
     rm -rf /var/run/httpd/* /run/httpd/* /tmp/httpd*
diff --git a/docker/keystone/keystone/extend_start.sh b/docker/keystone/keystone/extend_start.sh
index 9928856913..14a0a6f89d 100644
--- a/docker/keystone/keystone/extend_start.sh
+++ b/docker/keystone/keystone/extend_start.sh
@@ -15,7 +15,7 @@ function kolla_kubernetes {
 # results in the container not being able to restart. (bug #1489676, 1557036)
 if [[ "${KOLLA_BASE_DISTRO}" =~ debian|ubuntu ]]; then
     # Loading Apache2 ENV variables
-    source /etc/apache2/envvars
+    . /etc/apache2/envvars
     rm -rf /var/run/apache2/*
     APACHE_DIR="apache2"
 else
diff --git a/docker/magnum/magnum-base/extend_start.sh b/docker/magnum/magnum-base/extend_start.sh
index 8806cd2117..2e58c97765 100644
--- a/docker/magnum/magnum-base/extend_start.sh
+++ b/docker/magnum/magnum-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/magnum) != "755" ]]; then
     chmod 755 /var/log/kolla/magnum
 fi
 
-source /usr/local/bin/kolla_magnum_extend_start
+. /usr/local/bin/kolla_magnum_extend_start
diff --git a/docker/manila/manila-base/extend_start.sh b/docker/manila/manila-base/extend_start.sh
index 84bcd2ebef..c018416a33 100644
--- a/docker/manila/manila-base/extend_start.sh
+++ b/docker/manila/manila-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/manila) != "755" ]]; then
     chmod 755 /var/log/kolla/manila
 fi
 
-source /usr/local/bin/kolla_manila_extend_start
+. /usr/local/bin/kolla_manila_extend_start
diff --git a/docker/mistral/mistral-base/extend_start.sh b/docker/mistral/mistral-base/extend_start.sh
index f84c570c41..ac2980d6c7 100644
--- a/docker/mistral/mistral-base/extend_start.sh
+++ b/docker/mistral/mistral-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/mistral) != "755" ]]; then
     chmod 755 /var/log/kolla/mistral
 fi
 
-source /usr/local/bin/kolla_mistral_extend_start
+. /usr/local/bin/kolla_mistral_extend_start
diff --git a/docker/murano/murano-base/extend_start.sh b/docker/murano/murano-base/extend_start.sh
index 66dde46ed4..4d3b842b2d 100644
--- a/docker/murano/murano-base/extend_start.sh
+++ b/docker/murano/murano-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/murano) != "755" ]]; then
     chmod 755 /var/log/kolla/murano
 fi
 
-source /usr/local/bin/kolla_murano_extend_start
+. /usr/local/bin/kolla_murano_extend_start
diff --git a/docker/neutron/neutron-base/extend_start.sh b/docker/neutron/neutron-base/extend_start.sh
index e95dd280c6..12307fca19 100644
--- a/docker/neutron/neutron-base/extend_start.sh
+++ b/docker/neutron/neutron-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/neutron) != "755" ]]; then
     chmod 755 /var/log/kolla/neutron
 fi
 
-source /usr/local/bin/kolla_neutron_extend_start
+. /usr/local/bin/kolla_neutron_extend_start
diff --git a/docker/nova/nova-base/extend_start.sh b/docker/nova/nova-base/extend_start.sh
index 31ac31e4ba..eee0f16a1a 100644
--- a/docker/nova/nova-base/extend_start.sh
+++ b/docker/nova/nova-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/nova) != "755" ]]; then
     chmod 755 /var/log/kolla/nova
 fi
 
-source /usr/local/bin/kolla_nova_extend_start
+. /usr/local/bin/kolla_nova_extend_start
diff --git a/docker/openvswitch/openvswitch-base/extend_start.sh b/docker/openvswitch/openvswitch-base/extend_start.sh
index 67fc38537c..767194e04b 100644
--- a/docker/openvswitch/openvswitch-base/extend_start.sh
+++ b/docker/openvswitch/openvswitch-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/openvswitch) != "755" ]]; then
     chmod 755 /var/log/kolla/openvswitch
 fi
 
-source /usr/local/bin/kolla_openvswitch_extend_start
+. /usr/local/bin/kolla_openvswitch_extend_start
diff --git a/docker/sahara/sahara-base/extend_start.sh b/docker/sahara/sahara-base/extend_start.sh
index 74a9dbdddd..8245204d5a 100644
--- a/docker/sahara/sahara-base/extend_start.sh
+++ b/docker/sahara/sahara-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/sahara) != "755" ]]; then
     chmod 755 /var/log/kolla/sahara
 fi
 
-source /usr/local/bin/kolla_sahara_extend_start
+. /usr/local/bin/kolla_sahara_extend_start
diff --git a/docker/senlin/senlin-base/extend_start.sh b/docker/senlin/senlin-base/extend_start.sh
index 02886d4597..0a9c7bca13 100644
--- a/docker/senlin/senlin-base/extend_start.sh
+++ b/docker/senlin/senlin-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/senlin) != "755" ]]; then
     chmod 755 /var/log/kolla/senlin
 fi
 
-source /usr/local/bin/kolla_senlin_extend_start
+. /usr/local/bin/kolla_senlin_extend_start
diff --git a/docker/watcher/watcher-base/extend_start.sh b/docker/watcher/watcher-base/extend_start.sh
index b1fcd1974f..9e27a9cf0e 100644
--- a/docker/watcher/watcher-base/extend_start.sh
+++ b/docker/watcher/watcher-base/extend_start.sh
@@ -7,4 +7,4 @@ if [[ $(stat -c %a /var/log/kolla/watcher) != "755" ]]; then
     chmod 755 /var/log/kolla/watcher
 fi
 
-source /usr/local/bin/kolla_watcher_extend_start
+. /usr/local/bin/kolla_watcher_extend_start