title: no server suitable for synchronization found For NTP Service
body: <p>I had to build <code>ntp</code> packages from the source and install all of them on some hosts. After the installation, <code>ntpdate 1.us.pool.ntp.org</code> works for the synchronization. However, when I tried to do <code>ntpdate &lt;ip_add_of_another_host&gt;</code> it shows me the following error </p>
  
  <blockquote>
    <p>21 Jul 18:57:53 ntpdate[18287]: no server suitable for synchronization found</p>
  </blockquote>
  
  <p>Even more weirdly, sometimes <code>ntpdate &lt;ip_addr_of_another_host&gt;</code> works after I try the <code>ntpdate 1.us.pool.ntp.org</code></p>
  
  <p>My configuration file of the ntp server:</p>
  
  <pre><code># /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help
  
  driftfile /var/lib/ntp/ntp.drift
  
  
  # Enable this if you want statistics to be logged.
  #statsdir /var/log/ntpstats/
  
  statistics loopstats peerstats clockstats
  filegen loopstats file loopstats type day enable
  filegen peerstats file peerstats type day enable
  filegen clockstats file clockstats type day enable
  # Specify one or more NTP servers.
  
  # Use servers from the NTP Pool Project. Approved by Ubuntu Technical Board
  # on 2011-02-08 (LP: #104525). See http://www.pool.ntp.org/join.html for
  # more information.
  server 127.1.1.0 # local clock
  fudge 127.1.1.0 stratum 10
  # Access control configuration; see /usr/share/doc/ntp-doc/html/accopt.html for
  # details.  The web page &lt;http://support.ntp.org/bin/view/Support/AccessRestrictions&gt;
  # might also be helpful.
  #
  # Note that "restrict" applies to both servers and clients, so a configuration
  # that might be intended to block requests from certain clients could also end
  # up blocking replies from your own upstream servers.
  
  # By default, exchange time with everybody, but don't allow configuration.
  restrict -4 default kod notrap nomodify nopeer noquery
  restrict -6 default kod notrap nomodify nopeer noquery
  
  # Local users may interrogate the ntp server more closely.
  restrict 127.0.0.1
  restrict ::
  </code></pre>
  
  <p>I also tried the default configuration when I did <code>apt-get install ntp</code>, but it does not work as well. </p>