Add --ntp-pool option to installers

FreeIPA Server and Client now support option for chrony
configuration --ntp-pool.
This option may be used with option --ntp-server.

Resolves: https://pagure.io/freeipa/issue/7024
Reviewed-By: Rob Crittenden <rcritten@redhat.com>

ipaclient/install/client.py

@@ -2367,7 +2367,8 @@ def sync_time(options, fstore, statestore):
         ntp_servers = options.ntp_servers
 
     if ntp_servers:
-        synced_time = ntpconf.configure_chrony(ntp_servers, fstore, statestore)
+        synced_time = ntpconf.configure_chrony(ntp_servers, options.ntp_pool,
+                                               fstore, statestore)
     else:
         synced_time = False
         logger.warning("No SRV records of NTP servers found nor NTP server  "
@@ -3456,6 +3457,12 @@ class ClientInstallInterface(hostname_.HostNameInstallInterface,
     )
     ntp_servers = enroll_only(ntp_servers)
 
+    ntp_pool = knob(
+        str, None,
+        description="ntp server pool to use",
+    )
+    ntp_pool = enroll_only(ntp_pool)
+
     no_ntp = knob(
         None,
         description="do not configure ntp",
@@ -3556,6 +3563,10 @@ class ClientInstallInterface(hostname_.HostNameInstallInterface,
             raise RuntimeError(
                 "--ntp-server cannot be used together with --no-ntp")
 
+        if self.ntp_pool and self.no_ntp:
+            raise RuntimeError(
+                "--ntp-pool cannot be used together with --no-ntp")
+
         if self.no_nisdomain and self.nisdomain:
             raise RuntimeError(
                 "--no-nisdomain cannot be used together with --nisdomain")

ipaclient/install/ntpconf.py

@@ -37,7 +37,8 @@ def __backup_config(path, fstore=None):
         shutil.copy(path, "%s.ipasave" % (path))
 
 
-def configure_chrony(ntp_servers, fstore=None, sysstore=None, debug=False):
+def configure_chrony(ntp_servers, ntp_pool=None,
+                     fstore=None, sysstore=None, debug=False):
     if sysstore:
         module = 'chrony'
         sysstore.backup_state(module, "enabled",
@@ -58,6 +59,11 @@ def configure_chrony(ntp_servers, fstore=None, sysstore=None, debug=False):
         aug.remove('{}/server'.format(path))
         aug.remove('{}/pool'.format(path))
         aug.remove('{}/peer'.format(path))
+        if ntp_pool:
+            logger.debug("Setting server pool:")
+            logger.debug("'%s'", ntp_pool)
+            aug.set('{}/pool[last()+1]'.format(path), ntp_pool)
+            aug.set('{}/server[last()]/iburst'.format(path), None)
 
         logger.debug("Setting time servers:")
         for server in ntp_servers: