diff --git a/mozilla/security/nss/tests/common/init.sh b/mozilla/security/nss/tests/common/init.sh
index d56b7a77a04..ed2d3591c23 100644
--- a/mozilla/security/nss/tests/common/init.sh
+++ b/mozilla/security/nss/tests/common/init.sh
@@ -28,6 +28,13 @@ if [ ! -d ${TESTDIR} ]; then
    mkdir -p ${TESTDIR}
 fi
 
+if [ -z "${HOST}" ]; then 
+  echo "HOST environment variable is not defined."; exit 1
+fi
+if [ -z "${DOMSUF}" ]; then 
+  echo "DOMSUF environment variable is not defined."; exit 1
+fi
+
 if [ ! -s "${HOSTDIR}" ]; then
     version=1
     if [ -f ${TESTDIR}/${HOST} ]; then