Merge branch 'marka-shutdown-sync-v9_16' into 'v9_16'

Wait for named to start

See merge request isc-projects/bind9!4937

bin/tests/system/shutdown/tests-shutdown.py

@@ -171,7 +171,13 @@ def test_named_shutdown(named_port, control_port):
     # In both methods named should exit gracefully.
     for kill_method in ("rndc", "sigterm"):
         named_proc = launch_named()
-        time.sleep(2)
+        # wait for named to finish loading
+        for _ in range(10):
+            try:
+                resolver.query('version.bind', 'TXT', 'CH')
+                break
+            except (dns.resolver.NoNameservers, dns.exception.Timeout):
+                time.sleep(1)
 
         do_work(named_proc, resolver, rndc_cmd,
                 kill_method, n_workers=12, n_queries=16)