Retry chronyc waitsync only once

It's unlikely that a third chrony synchronization attempt is going to
succeed after the the first two attempts have failed. Perform more
retries with smaller timeout.

This speed up installer by 11 seconds on systems without fully
configured chronyd or no chronyd (e.g. containers).

Related: https://pagure.io/freeipa/issue/8521
Signed-off-by: Christian Heimes <cheimes@redhat.com>
Reviewed-By: Francois Cami <fcami@redhat.com>

ipaclient/install/timeconf.py

@@ -82,13 +82,16 @@ def sync_chrony():
     # Restart chronyd
     services.knownservices.chronyd.restart()
 
-    sync_attempt_count = 3
-    # chrony attempt count to sync with configiured servers
-    # each next attempt is tried after 10seconds of timeot
-    # 3 attempts means: if first immidiate attempt fails
-    # there is 10s delay between next attempts
-
-    args = [paths.CHRONYC, 'waitsync', str(sync_attempt_count), '-d']
+    # chrony attempt count to sync with configured servers. Each attempt is
+    # retried after $interval seconds.
+    # 4 attempts with 3s interval result in a maximum delay of 9 seconds.
+    sync_attempt_count = 4
+    sync_attempt_interval = 3
+    args = [
+        paths.CHRONYC, '-d', 'waitsync',
+        # max-tries, max-correction, max-skew, interval
+        str(sync_attempt_count), '0', '0', str(sync_attempt_interval)
+    ]
 
     try:
         logger.info('Attempting to sync time with chronyc.')