diff --git a/src/network.sh b/src/network.sh
index 3bfaa2e..b2e466c 100644
--- a/src/network.sh
+++ b/src/network.sh
@@ -239,11 +239,11 @@ getInfo() {
   fi
 
   if [ -z "$MAC" ]; then
-    # Generate MAC address based on hostname
+    # Generate MAC address based on Docker container ID in hostname
     MAC=$(echo "$HOST" | md5sum | sed 's/^\(..\)\(..\)\(..\)\(..\)\(..\).*$/02:\1:\2:\3:\4:\5/')
   fi
 
-  VM_NET_MAC="${MAC//-/:}"
+  VM_NET_MAC="${MAC,,//-/:}"
 
   if [[ ${#VM_NET_MAC} == 12 ]]; then
     m="$VM_NET_MAC"