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    Web page:
<a class="moz-txt-link-freetext" href="https://kb.isc.org/article/AA-00502/0/A-Basic-Guide-to-Configuring-DHCP-Failover.htmlge">https://kb.isc.org/article/AA-00502/0/A-Basic-Guide-to-Configuring-DHCP-Failover.htmlge</a>:
    <a class="moz-txt-link-freetext"
      href="http://www.ipamworldwide.com/ipam/dhcp-declare-failover.html"></a><br>
    <br>
    The ports used in the fail-over example are not necessarily "wrong"
    but should<br>
    reflect the ports already assigned for fail-over communication:<br>
    <font color="#993300"><tt>dhcp-failover   647/tcp                 #
        DHCP Failover</tt><tt><br>
      </tt><tt>dhcp-failover   647/udp                 # DHCP Failover</tt><tt><br>
      </tt><tt>dhcp-failover2  847/tcp                 # dhcp-failover 2</tt><tt><br>
      </tt><tt>dhcp-failover2  847/udp                 # dhcp-failover 2</tt><tt><br>
      </tt></font><br>
    Also, selinux on Red Hat systems allows those ports without creating
    an exception:<br>
    <font color="#993300"><tt>[0:root@c3po dhcp]$ semanage port -l |
        grep dhcpd</tt><tt><br>
      </tt><tt>dhcpd_port_t                   tcp      547, 548, 647,
        847, 7911</tt><tt><br>
      </tt><tt>dhcpd_port_t                   udp      67, 547, 548,
        647, 847</tt><tt><br>
      </tt></font><br>
    Thanks for the online documentation.  I'm hoping to improve it just
    a little bit.<br>
    <br>
    Bill<br>
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