From 2e4f342c6eada50d4c99c5f7a816dfcfebd679ff Mon Sep 17 00:00:00 2001
From: Jamie Cameron <jcameron@webmin.com>
Date: Sun, 22 Jun 2008 06:46:35 +0000
Subject: [PATCH] Randomize sync time

---
 time/CHANGELOG      |  2 ++
 time/index.cgi      |  5 +++--
 time/postinstall.pl | 18 ++++++++++++++++++
 3 files changed, 23 insertions(+), 2 deletions(-)
 create mode 100644 time/postinstall.pl

diff --git a/time/CHANGELOG b/time/CHANGELOG
index 2d1708cd2..50c8621b1 100644
--- a/time/CHANGELOG
+++ b/time/CHANGELOG
@@ -16,3 +16,5 @@ Display a more complete message if unable to get the hardware time from hwclock.
 ---- Changes since 1.390 ----
 Changed the main page to use tabs to split up the system time, timezone and sync sections.
 Re-wrote all user interface code to use Webmin's new UI library.
+---- Changes since 1.420 ----
+The default NTP sync time is now set randomly instead of at midnight, and any existing automatic sync done at midnight is changed to a random time. This reduces load on public NTP servers.
diff --git a/time/index.cgi b/time/index.cgi
index 85209eeb2..c3b14612d 100755
--- a/time/index.cgi
+++ b/time/index.cgi
@@ -166,8 +166,9 @@ if ( ( !$access{ 'sysdate' } && &has_command( "date" ) || !$access{ 'hwdate' } &
 	print &ui_table_row($text{'index_sched'},
 		&ui_radio("sched", $job ? 1 : 0,
 		  [ [ 0, $text{'no'} ], [ 1, $text{'index_schedyes'} ] ]));
-	$job ||= { 'mins' => '0',
-		   'hours' => '0',
+	&seed_random();
+	$job ||= { 'mins' => int(rand()*60),
+		   'hours' => int(rand()*24),
 		   'days' => '*',
 		   'months' => '*',
 		   'weekdays' => '*' };
diff --git a/time/postinstall.pl b/time/postinstall.pl
new file mode 100644
index 000000000..9877b9277
--- /dev/null
+++ b/time/postinstall.pl
@@ -0,0 +1,18 @@
+
+require 'time-lib.pl';
+
+# Change time sync jobs running at midnight to a random time, to stop
+# overloading public NTP servers
+sub module_install
+{
+&foreign_require("cron", "cron-lib.pl");
+local $job = &find_cron_job();
+if ($job && $job->{'mins'} eq '0' && $job->{'hours'} eq '0') {
+	# Midnight .. fix it
+	&seed_random();
+	$job->{'mins'} = int(rand()*60);
+	$job->{'hours'} = int(rand()*24);
+	&cron::change_cron_job($job);
+	}
+}
+