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@@ -572,28 +572,28 @@ temporarily override a list of interface names and listen on all interfaces.
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<section id="dhcpinform-unicast-issues">
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<title>Issues with unicast responses to DHCPINFORM</title>
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- <para>The use of the UDP sockets has certain benefits in the deployments
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- where the server receives a relayed traffic only. These benefits are
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+ <para>The use of UDP sockets has certain benefits in deployments
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+ where the server receives only relayed traffic. These benefits are
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mentioned in the <xref linkend="dhcp4-interface-configuration"/>. From
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the administrator's perspective it is often desired to be able to
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configure the system's firewall to filter out the unwanted traffic, and
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the use of UDP sockets faciliates it. However, the administrator must
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also be aware of the implications related to filtering certain types
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- of traffic as it my impair the DHCP server's operation.
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+ of traffic as it may impair the DHCP server's operation.
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</para>
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<para>In this section we are focusing on the case when the server
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receives the DHCPINFORM message from the client via a relay. According
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to the <ulink url="http://tools.ietf.org/html/rfc2131">RFC 2131</ulink>,
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- the server should unicast DHCPACK response to the address carried in
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+ the server should unicast the DHCPACK response to the address carried in
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the 'ciaddr' field. When the UDP socket is in use, the DHCP server
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relies on the low level functions of an operating system to build the
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- data link, IP and UDP layer of the outgoing message. Typically, the
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+ data link, IP and UDP layers of the outgoing message. Typically, the
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OS will first use ARP to obtain the client's link layer address to be
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inserted into the frame's header, if the address is not cached from
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- the previous transaction that the client had with the server.
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+ a previous transaction that the client had with the server.
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When the ARP exchange is successful, the DHCP message can be unicast
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- to the client, using the address obtained.
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+ to the client, using the obtained address.
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</para>
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<para>Some system administrators block ARP messages in their network,
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@@ -616,9 +616,9 @@ temporarily override a list of interface names and listen on all interfaces.
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of the DHCPINFORM message into the link layer.
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</para>
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- <para>The server administrators willing to support DHCPINFORM
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- messages via the relays should not block ARP traffic in their
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- networks or use the raw sockets instead of the UDP sockets.
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+ <para>Server administrators willing to support DHCPINFORM
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+ messages via relays should not block ARP traffic in their
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+ networks or should use raw sockets instead of UDP sockets.
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</para>
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</section>
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