Add logic to show uppercase warning message when appropriate

salt/common/tools/sbin/so-common

@@ -160,6 +160,14 @@ fail() {
 	exit 1
 }
 
+fqdn_lowercase() {
+	local fqdn=$1
+
+	echo "$fqdn" | grep -qP '(?=^.{4,253}$)(^((?!-)[a-z0-9-]{0,62}[a-z0-9]\.)+[a-z]{2,63}$)' \
+		&& return 0 \
+		|| return 1
+}
+
 get_random_value() {
 	length=${1:-20}
 	head -c 5000 /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w $length | head -n 1
@@ -186,6 +194,12 @@ header() {
 	printf '%s\n' "" "$banner" " $*" "$banner" 
 }
 
+hostname_lowercase() {
+	local hostname=$1
+
+	[[ $hostname =~ ^[a-z0-9\-]+$ ]] && return 0 || return 1
+}
+
 init_monitor() {
 	MONITORNIC=$1