diff --git a/system_setup/install.sh b/system_setup/install.sh
index 47397e8..e289bd2 100755
--- a/system_setup/install.sh
+++ b/system_setup/install.sh
@@ -8,6 +8,8 @@
 #
 # Run as root on a target machine before any Kickstart installation.
 
+[[ "$EUID" -eq 0 ]] || { echo "ERROR: This script must be run as root." >&2; exit 1; }
+
 SHRINK_MIB=4096
 OEMDRV_LABEL="OEMDRV"
 MOUNT_POINT="/opt/sys_config"