diff --git a/installers/mgmt-cluster/library/functions.sh b/installers/mgmt-cluster/library/functions.sh
new file mode 100755
index 0000000..638a1d2
--- /dev/null
+++ b/installers/mgmt-cluster/library/functions.sh
@@ -0,0 +1,91 @@
+#######################################################################################
+# Copyright ETSI Contributors and Others.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#######################################################################################
+
+
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+BLUE='\033[0;34m'
+CYAN='\033[0;36m'
+RESET='\033[0m'
+
+# Colored messages (blue is the default)
+# Examples:
+#   m "hello world"
+#   m "hello world" "$GREEN"
+function m() {
+  local COLOR=${2:-$BLUE}
+  echo -e "$COLOR$1$RESET"
+}
+
+function copy_function() {
+  local ORIG_FUNC=$(declare -f $1)
+  local NEWNAME_FUNC="$2${ORIG_FUNC#$1}"
+  eval "$NEWNAME_FUNC"
+}
+
+function replace_text() {
+  local FILE=$1
+  local START=$2
+  local END=$3
+  local NEW=$4
+  local T=$(mktemp)
+  head -n $((START-1)) "$FILE" > "$T"
+  echo "$NEW" >> "$T"
+  tail -n +$((END+1)) "$FILE" >> "$T"
+  mv "$T" "$FILE"
+}
+
+function insert_text() {
+  local FILE=$1
+  local START=$2
+  local NEW=$3
+  local T=$(mktemp)
+  head -n $((START-1)) "$FILE" > "$T"
+  echo "$NEW" >> "$T"
+  tail -n +$START "$FILE" >> "$T"
+  mv "$T" "$FILE"
+}
+
+function remove_text() {
+  local FILE=$1
+  local START=$2
+  local END=$3
+  local T=$(mktemp)
+  head -n $((START-1)) "$FILE" > "$T"
+  tail -n +$((END+1)) "$FILE" >> "$T"
+  mv "$T" "$FILE"
+}
+
+function envsubst_cp() {
+  local FROM_FILE=$1
+  local TO_FILE=$2
+  mkdir --parents "$(dirname "$TO_FILE")"
+  cat "$FROM_FILE" | envsubst > "$TO_FILE"
+}
+
+function envsubst_dir() {
+  local FROM_DIR=$1
+  local TO_DIR=$2
+  rm --recursive --force "$TO_DIR"
+  mkdir --parents "$TO_DIR"
+  pushd "$FROM_DIR" > /dev/null
+  local F
+  find . -type f | while read F; do
+    envsubst_cp "$F" "$TO_DIR/$F"
+  done
+  popd > /dev/null
+}