diff --git a/.gitignore b/.gitignore
index bc2012c57d..3a151bbe9a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -68,3 +68,4 @@ tests/tests_*
 tests/*.log
 tests/*.trs
 test-suite.log
+tags
diff --git a/src/libcrun/container.c b/src/libcrun/container.c
index a918628ab8..c1f4913a36 100644
--- a/src/libcrun/container.c
+++ b/src/libcrun/container.c
@@ -1187,6 +1187,13 @@ container_init_setup (void *args, pid_t own_pid, char *notify_socket, int sync_s
   if (clearenv ())
     return crun_make_error (err, errno, "clearenv");
 
+  // set primary process to 1 explicitly if nothing is configured and LISTEN_FD is not set
+  if (getenv ("LISTEN_PID") == NULL && entrypoint_args->context->preserve_fds > 0)
+    {
+      setenv ("LISTEN_PID", "1", 1);
+      libcrun_warning ("setting LISTEN_PID=1 since no previous configuration was found");
+    }
+
   if (def->process)
     {
       size_t i;