diff --git a/kokoro/rootfs.sh b/kokoro/rootfs.sh
index 831b954..089a836 100644
--- a/kokoro/rootfs.sh
+++ b/kokoro/rootfs.sh
@@ -7,7 +7,7 @@
 source build/setup.sh
 popd
 
-export IS_EXTERNAL=false
+export IS_EXTERNAL=true
 export FETCH_PACKAGES=false
 export PREBUILT_DOCKER_ROOT=${KOKORO_GFILE_DIR}