[deployment-guide/comm-rel: 20/35] Added ntpdate description as suggested by mlichvar.

[dsilas]

commit bbfb614b515a5f9e9768fa322fa31ada0c0871f5
Author: Jaromir Hradilek <jhradile at redhat.com>
Date:   Thu Jun 3 11:16:57 2010 +0200

    Added ntpdate description as suggested by mlichvar.

 en-US/Date_and_Time_Configuration.xml |   55 +++++++++++++++++++++++++++++++--
 1 files changed, 52 insertions(+), 3 deletions(-)
---
diff --git a/en-US/Date_and_Time_Configuration.xml b/en-US/Date_and_Time_Configuration.xml
index 5b14455..e307d83 100644
--- a/en-US/Date_and_Time_Configuration.xml
+++ b/en-US/Date_and_Time_Configuration.xml
@@ -101,6 +101,7 @@
         <primary>
           <command>ntpd</command>
         </primary>
+        <see>NTP</see>
       </indexterm>
       <para>
         If you prefer an automatic setup, select the checkbox labeled <guilabel>Synchronize date and time over the network</guilabel> instead. This will display the list of available NTP servers as shown in <xref linkend="figu-Date_and_Time_Configuration-Network_Time_Protocol" />.
@@ -208,17 +209,25 @@ Password: </screen>
       <procedure>
         <step>
           <para>
-            <emphasis>Change the current date.</emphasis> Type the command in the following form at a shell prompt, replacing the <replaceable>YYYY</replaceable> with a four-digit year, <replaceable>MM</replaceable> with a two-digit month, and <replaceable>DD</replaceable> with a two-digit day of the month (e.g., <emphasis>2010-06-02</emphasis>):
+            <emphasis>Change the current date.</emphasis> Type the command in the following form at a shell prompt, replacing the <replaceable>YYYY</replaceable> with a four-digit year, <replaceable>MM</replaceable> with a two-digit month, and <replaceable>DD</replaceable> with a two-digit day of the month:
           </para>
           <screen>~]# <command>date +%D -s <replaceable>YYYY-MM-DD</replaceable></command></screen>
+          <para>
+            For example, to set the date to 2 June 2010, type:
+          </para>
+          <screen>~]# <command>date +%D -s 2010-06-02</command></screen>
         </step>
         <step>
           <para>
-            <emphasis>Change the current time.</emphasis> Use the following command, where <replaceable>HH</replaceable> stands for an hour, <replaceable>MM</replaceable> is a minute, and <replaceable>SS</replaceable> is a second, all typed in the two-digit form (e.g., <emphasis>23:26:00</emphasis>):
+            <emphasis>Change the current time.</emphasis> Use the following command, where <replaceable>HH</replaceable> stands for an hour, <replaceable>MM</replaceable> is a minute, and <replaceable>SS</replaceable> is a second, all typed in a two-digit form:
           </para>
           <screen>~]# <command>date +%T -s <replaceable>HH:MM:SS</replaceable></command></screen>
           <para>If your system clock is set to use <acronym>UTC</acronym> (Coordinated Universal Time), add the following option:</para>
           <screen>~]# <command>date +%T -s <replaceable>HH:MM:SS</replaceable> -u</command></screen>
+          <para>
+            For instance, to set the system clock to 11:26 PM using the <acronym>UTC</acronym>, type:
+          </para>
+          <screen>~]# <command>date +%T -s 23:26:00 -u</command></screen>
         </step>
       </procedure>
       <para>
@@ -237,6 +246,46 @@ Wed Jun  2 11:58:48 CEST 2010</screen>
         <primary>Network Time Protocol</primary>
         <see>NTP</see>
       </indexterm>
+      <indexterm>
+        <primary>NTP</primary>
+        <secondary>
+          <command>ntpdate</command>
+        </secondary>
+      </indexterm>
+      <indexterm>
+        <primary>
+          <command>ntpdate</command>
+        </primary>
+        <see>NTP</see>
+      </indexterm>
+      <para>
+        As opposed to the manual setup described above, you can also synchronize the system clock with a remote server over the Network Time Protocol (<acronym>NTP</acronym>). For the one-time synchronization only, use the <application>ntpdate</application> command:
+      </para>
+      <procedure>
+        <step>
+          <para>
+            Firstly, check whether the selected NTP server is accessible:
+          </para>
+          <screen>~]# <command>ntpdate -q <replaceable>server_address</replaceable></command></screen>
+          <para>
+            For example:
+          </para>
+          <screen>~]# <command>ntpdate -q 0.rhel.pool.ntp.org</command></screen>
+        </step>
+        <step>
+          <para>
+            When you find a satisfactory server, run the <application>ntpdate</application> command followed with on or more server adresses:
+          </para>
+          <screen>~]# <command>ntpdate <replaceable>server_address...</replaceable></command></screen>
+          <para>
+            For instance:
+          </para>
+          <screen>~]# <command>ntpdate 0.rhel.pool.ntp.org 1.rhel.pool.ntp.org</command></screen>
+          <para>
+            Unless an error message is displayed, the system time should now be set. You can check the current setting typing <command>date</command> without any additional arguments as shown in <xref linkend="sect-Date_and_Time_Configuration-Command_Line_Configuration-Date_and_Time" />.
+          </para>
+        </step>
+      </procedure>
       <indexterm significance="normal">
         <primary>NTP</primary>
         <secondary>configuring</secondary>
@@ -254,7 +303,7 @@ Wed Jun  2 11:58:48 CEST 2010</screen>
         <see>NTP</see>
       </indexterm>
       <para>
-        As opposed to the manual setup described above, you can also synchronize the system clock with a remote server over the Network Time Protocol (<acronym>NTP</acronym>). 
+        However, the more convenient way is to set the <application>ntpd</application> daemon to synchronize the time at boot time automatically:
       </para>
       <procedure>
         <step>