diff --git a/tools/test/bin/onos-verify-cell b/tools/test/bin/onos-verify-cell
index 284a7c4..55c2b32 100755
--- a/tools/test/bin/onos-verify-cell
+++ b/tools/test/bin/onos-verify-cell
@@ -15,7 +15,7 @@
             let err=0
             break
         fi
-        let err=$?+$err
+        let err=1+$err
     done
     if [ $err -ne 0 ]; then
         exit 1