Differences

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--- ntp [2009/06/19 12:25]
greebo
+++ ntp [2014/06/27 10:33] (current)
@@ Line 1: / Line 1: @@
+=== OpenNTP ===
 ipv6 ntp pool - eu.ntp.sixxs.net\\
 \\
 ubuntu/debian:\\
-ln -s /etc/openntpd/ntp.conf /etc/ntp.conf
+ln -s /etc/openntpd/ntpd.conf /etc/ntpd.conf
+=== NTP ===
+==== Setup Restrict values in ''ntp.conf'' ====
+**see:** [[http://www.thegeekstuff.com/2014/06/linux-ntp-server-client/|http://www.thegeekstuff.com/2014/06/linux-ntp-server-client/]]
+Modify the ''/etc/ntp.conf'' file to make sure it has the following two restrict lines.
+<code>
+# Permit time synchronization with our time source, but do not
+# permit the source to query or modify the service on this system.
+restrict default kod nomodify notrap nopeer noquery
+restrict -6 default kod nomodify notrap nopeer noquery
+</code>
+The first restrict line allows other clients to query your time server. This restrict line has the following parameters
+  * noquery prevents dumping status data from ntpd.
+  * notrap prevents control message trap service.
+  * nomodify prevents all ntpq queries that attempts to modify the server.
+  * nopeer prevents all packets that attempts to establish a peer association.
+  * Kod – Kiss-o-death packet is to be sent to reduce unwanted queries
+The value -6 in the second line allows forces the DNS resolution to the IPV6 address resolution. For more information on the access parameters list, Please refer to documentation on “man ntp_acc”