kea/src/bin/perfdhcp/perfdhcp.xml

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<refentry>
    <refentryinfo>
        <date>February 19, 2014</date>
    </refentryinfo>

    <refmeta>
        <refentrytitle>perfdhcp</refentrytitle>
        <manvolnum>8</manvolnum>
        <refmiscinfo>Kea</refmiscinfo>
    </refmeta>

    <refnamediv>
        <refname>perfdhcp</refname>
        <refpurpose>DHCP benchmarking tool</refpurpose>
    </refnamediv>

    <docinfo>
        <copyright>
            <year>2014</year>
            <holder>Internet Systems Consortium, Inc. ("ISC")</holder>
        </copyright>
    </docinfo>

    <refsynopsisdiv>
        <cmdsynopsis>
            <command>perfdhcp</command>
            <arg><option>-1</option></arg>
            <arg><option>-4|-6</option></arg>
            <arg><option>-a <replaceable class="parameter">aggressivity</replaceable></option></arg>
            <arg><option>-b <replaceable class="parameter">base</replaceable></option></arg>
            <arg><option>-B</option></arg>
            <arg><option>-c</option></arg>
            <arg><option>-d <replaceable class="parameter">drop-time</replaceable></option></arg>
            <arg><option>-D <replaceable class="parameter">max-drop</replaceable></option></arg>
            <arg><option>-e <replaceable class="parameter">lease-type</replaceable></option></arg>
            <arg><option>-E <replaceable class="parameter">time-offset</replaceable></option></arg>
            <arg><option>-f <replaceable class="parameter">renew-rate</replaceable></option></arg>
            <arg><option>-F <replaceable class="parameter">release-rate</replaceable></option></arg>
            <arg><option>-h</option></arg>
            <arg><option>-i</option></arg>
            <arg><option>-I <replaceable class="parameter">ip-offset</replaceable></option></arg>
            <arg><option>-l <replaceable class="parameter">local-address|interface</replaceable></option></arg>
            <arg><option>-L <replaceable class="parameter">local-port</replaceable></option></arg>
            <arg><option>-n <replaceable class="parameter">num-request</replaceable></option></arg>
            <arg><option>-O <replaceable class="parameter">random-offset</replaceable></option></arg>
            <arg><option>-p <replaceable class="parameter">test-period</replaceable></option></arg>
            <arg><option>-P <replaceable class="parameter">preload</replaceable></option></arg>
            <arg><option>-r <replaceable class="parameter">rate</replaceable></option></arg>
            <arg><option>-R <replaceable class="parameter">num-clients</replaceable></option></arg>
            <arg><option>-s <replaceable class="parameter">seed</replaceable></option></arg>
            <arg><option>-S <replaceable class="parameter">srvid-offset</replaceable></option></arg>
            <arg><option>-t <replaceable class="parameter">report</replaceable></option></arg>
            <arg><option>-T <replaceable class="parameter">template-file</replaceable></option></arg>
            <arg><option>-v</option></arg>
            <arg><option>-W <replaceable class="parameter">wrapped</replaceable></option></arg>
            <arg><option>-x <replaceable class="parameter">diagnostic-selector</replaceable></option></arg>
            <arg><option>-X <replaceable class="parameter">xid-offset</replaceable></option></arg>
            <arg>server</arg>
        </cmdsynopsis>
    </refsynopsisdiv>

    <refsect1>
        <title>DESCRIPTION</title>
        <para>
            <command>perfdhcp</command> is a DHCP benchmarking tool. It
            provides a way of measuring the performance of DHCP servers by
            generating large amounts of traffic from simulated multiple
            clients. It is able to test both IPv4 and IPv6 servers, and
            provides statistics concerning response times and the number of
            requests that are dropped.
        </para>

        <para>
            By default, tests are run using the full four-packet exchange
            sequence (DORA for DHCPv4, SARR for DHCPv6).  An option is
            provided to run tests using the initial two-packet exchange (DO
            and SA) instead.  It is also possible to configure perfdhcp to
            send DHCPv6 RENEW and RELEASE messages at a specified rate in
            parallel with the DHCPv6 four-way exchanges.
        </para>

        <para>
            When running a performance test, <command>perfdhcp</command>
            will exchange packets with the server under test as fast as
            possible unless the <option>-r</option> is given to limit the
            request rate. The length of the test can be limited by setting
            a threshold on any or all of the number of requests made by
            <command>perfdhcp</command>, the elapsed time, or the number of
            requests dropped by the server.
        </para>
    </refsect1>

    <refsect1>
        <title>TEMPLATES</title>
        <para>
            To allow the contents of packets sent to the server to be
            customized, <command>perfdhcp</command> allows the specification
            of template files that determine the contents of the packets.
            For example, the customized packet may contain a DHCPv6 ORO to
            request a set of options to be returned by the server, or it may
            contain the Client FQDN option to request that server performs DNS
            updates. This may be used to discover performance bottlenecks for
            different server configurations (e.g. DDNS enabled or disabled).
        </para>

        <para>
            Up to two template files can be specified on the command line,
            each file representing the contents of a particular type of
            packet,  the type being determined by the test being carried out.
            For example, if testing DHCPv6:
        </para>

        <itemizedlist>
            <listitem>
                <para>
                    With no template files specified on the command line,
                    <command>perfdhcp</command> will generate both SOLICIT
                    and REQUEST packets.
                </para>
            </listitem> <listitem>
                <para>
                    With one template file specified, that file
                    will be used as the pattern for SOLICIT packets:
                    <command>perfdhcp</command> will generate the REQUEST
                    packets.
                </para>
            </listitem> <listitem>
                <para>
                    With two template files given on the command line, the
                    first will be used as the pattern for SOLICIT packets,
                    the second as the pattern for REQUEST packets.
                </para>
            </listitem>
        </itemizedlist>

        <para>
            (Similar determination applies to DHCPv4's DISCOVER and REQUEST
            packets.)
        </para>

        <para>
            The template file holds the DHCP packet represented as a stream
            of ASCII hexadecimal digits and it excludes any IP/UDP stack
            headers. The template file must not contain any characters other
            than hexadecimal digits and spaces. Spaces are discarded when the
            template file is parsed (so in the file, '12B4' is the same as
            '12 B4' which is the same as '1 2 B 4')
        </para>

        <para>
            The template files should be used in conjunction with the command
            line parameters which specify offsets of the data fields being
            modified in outbound packets. For example, the <option>-E
            <replaceable class="parameter">time-offset</replaceable></option>
            switch specifies the offset of the DHCPv6 Elapsed Time option in
            the packet template. If the offset is specified, perfdhcp will
            inject the current elapsed time value into this field before
            sending the packet to the server.
        </para>

        <para>
            In many scenarios, <command>perfdhcp</command> needs to simulate
            multiple clients (having unique client identifier). Since
            packets for each client are generated from the same template
            file, it is necessary to randomize the client identifier (or HW
            address in DHCPv4) in the packet created from it. The <option>-O
            <replaceable class="parameter">random-offset</replaceable></option>
            option allows specification of the offset in the template where
            randomization should be performed. It is important to note that
            this offset points to the end (not the beginning) of the client
            identifier (or HW address field). The number of bytes being
            randomized depends on the number of simulated clients. If the
            number of simulated clients is between 1 and 255, only one byte
            (to which randomization offset points) will be randomized. If the
            number of simulated clients is between 256 and 65535, two bytes
            will be randomized. Note, that two last bytes of the client
            identifier will be randomized in this case: the byte which
            randomization offset parameter points to, and the one which
            precedes it (random-offset - 1). If the number of simulated
            clients exceeds 65535, three bytes will be randomized; and so on.
        </para>

        <para>
            Templates may be currently used to generate packets being sent
            to the server in 4-way exchanges, i.e. SOLICIT, REQUEST (DHCPv6)
            and DISCOVER, REQUEST (DHCPv4). They cannot be used when RENEW
            or RELEASE packets are being sent.
        </para>

    </refsect1>

    <refsect1>
        <title>OPTIONS</title>

        <variablelist>

            <varlistentry>
                <term><option>-1</option></term>
                <listitem>
                    <para>
                        Take the server-ID option from the first received
                        message.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-4</option></term>
                <listitem>
                    <para>
                        DHCPv4 operation; this is the default. It is
                        incompatible with the <option>-6</option> option.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-6</option></term>
                <listitem>
                    <para>
                        DHCPv6 operation. This is incompatible with the
                        <option>-4</option> option.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-a <replaceable class="parameter">aggressivity</replaceable></option></term>
                <listitem>
                    <para>
                        When the target sending rate is not yet reached,
                        control how many exchanges are initiated before the
                        next pause. This is a positive integer and defaults
                        to 1.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-b <replaceable class="parameter">basetype=value</replaceable></option></term>
                <listitem>
                    <para>
                        The base MAC or DUID used to simulate
                        different clients. The <replaceable
                        class="parameter">basetype</replaceable> may be "mac"
                        or "duid". (The keyword "ether" may alternatively
                        used for MAC.)  The <option>-b</option> option can be
                        specified multiple times. The MAC address must consist
                        of six octets separated by single (:) or double (::)
                        colons, for example: mac=00:0c:01:02:03:04. The DUID
                        value is a hexadecimal string: it must be at least six
                        octets long and must not be longer than 64 bytes and
                        the length must be less than 128 hexadecimal digits,
                        for example: duid=0101010101010101010110111F14.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-d <replaceable class="parameter">drop-time</replaceable></option></term>
                <listitem>
                    <para>
                        Specify the time after which a request is treated
                        as having been lost.  The value is given in seconds
                        and may contain a fractional component.  The default
                        is 1 second.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-e <replaceable class="parameter">lease-type</replaceable></option></term>
                <listitem>
                    <para>
                        Specifies the type of lease being requested from
                        the server. It may be one of the following:
                    </para>

                    <variablelist>
                        <varlistentry>
                            <term>address-only</term>
                            <listitem>
                                <para>Only regular addresses (v4 or v6) will be requested.</para>
                            </listitem>
                        </varlistentry>

                        <varlistentry>
                            <term>prefix-only</term>
                            <listitem>
                                <para>Only IPv6 prefixes will be requested.</para>
                            </listitem>
                        </varlistentry>

                        <varlistentry>
                            <term>address-and-prefix</term>
                            <listitem>
                                <para>Both IPv6 addresses and prefixes will be requested.</para>
                            </listitem>
                        </varlistentry>
                    </variablelist>

                    <para>
                        The <option>-e prefix-only</option> and <option>-e
                        address-and-prefix</option> forms may not be used
                        with the <option>-4</option> option.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
              <term><option>-f <replaceable class="parameter">renew-rate</replaceable></option></term>
              <listitem>
                <para>
                    Rate at which DHCPv4 or DHCPv6 renew requests are sent
                    to a server. This value is only valid when used in conjunction
                    with the exchange rate (given by <option>-r <replaceable
                    class="parameter">rate</replaceable></option>).
                    Furthermore the sum of this value and the release-rate
                    (given by <option>-F <replaceable class="parameter">
                    rate</replaceable></option>) must be equal to or less than
                    the exchange rate.
                </para>
              </listitem>
            </varlistentry>


            <varlistentry>
                <term><option>-h</option></term>
                <listitem>
                    <para>
                        Print help and exit.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-i</option></term>
                <listitem>
                    <para>
                        Do only the initial part of the exchange:
                        DISCOVER-OFFER if <option>-4</option> is selected,
                        SOLICIT-ADVERTISE if <option>-6</option> is chosen.
                    </para>

                    <para>
                        <option>-i</option> is incompatible with the following
                        options: <option>-1</option>, <option>-d</option>,
                        <option>-D</option>, <option>-E</option>,
                        <option>-S</option>, <option>-I</option> and
                        <option>-F</option>.  In addition, it cannot be
                        used with multiple instances of <option>-O</option>,
                        <option>-T</option> and <option>-X</option>.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-l <replaceable class="parameter">local-addr|interface</replaceable></option></term>
                <listitem>
                    <para>
                        For DHCPv4 operation, specify the local
                        hostname/address to use when communicating with
                        the server.  By default, the interface address
                        through which traffic would normally be routed to
                        the server is used.  For DHCPv6 operation, specify
                        the name of the network interface through which
                        exchanges are initiated.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-L <replaceable class="parameter">local-port</replaceable></option></term>
                <listitem>
                    <para>
                        Specify the local port to use.  This must be zero
                        or a positive integer up to 65535.  A value of 0
                        (the default) allows <command>perfdhcp</command>
                        to choose its own port.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-P <replaceable class="parameter">preload</replaceable></option></term>
                <listitem>
                    <para>
                        Initiate <replaceable
                        class="parameter">preload</replaceable>
                        exchanges back to back at startup.  <replaceable
                        class="parameter">preload</replaceable> must be 0
                        (the default) or a positive integer.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-r <replaceable class="parameter">rate</replaceable></option></term>
                <listitem>
                    <para>
                        Initiate <replaceable
                        class="parameter">rate</replaceable> DORA/SARR (or
                        if <option>-i</option> is given, DO/SA) exchanges
                        per second.  A periodic report is generated showing
                        the number of exchanges which were not completed,
                        as well as the average response latency.  The program
                        continues until interrupted, at which point a final
                        report is generated.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-R <replaceable class="parameter">num-clients</replaceable></option></term>
                <listitem>
                    <para>
                        Specify how many different clients are used. With
                        a value of 1 (the default), all requests seem
                        to come from the same client. <replaceable
                        class="parameter">num-clients</replaceable> must be
                        a positive number.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-s <replaceable class="parameter">seed</replaceable></option></term>
                <listitem>
                    <para>
                        Specify the seed for randomization, making runs of
                        <command>perfdhcp</command> repeatable. <replaceable
                        class="parameter">seed</replaceable> is 0 or a positive
                        integer. The value 0 means that a seed is not used;
                        this is the default.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-T <replaceable class="parameter">template-file</replaceable></option></term>
                <listitem>
                    <para>
                        The name of a file containing the template to use as a
                        stream of hexadecimal digits.  This may be specified
                        up to two times and controls the contents of the
                        packets sent (see the "TEMPLATES" section above).
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-v</option></term>
                <listitem>
                    <para>
                        Print the version of this program.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-w <replaceable class="parameter">wrapped</replaceable></option></term>
                <listitem>
                    <para>
                        Command to call with  a single parameter of "start"
                        or "stop" at the beginning/end of the program.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-x <replaceable class="parameter">diagnostic-selector</replaceable></option></term>
                <listitem>
                    <para>
                        Include extended diagnostics
                        in the output.  <replaceable
                        class="parameter">diagnostic-selector</replaceable>
                        is a string of single-keywords specifying the
                        operations for which verbose output is desired.
                        The selector key letters are:
                    </para>

                    <variablelist>
                        <varlistentry>
                            <term>a</term>
                            <listitem>
                                <para>Print the decoded command line arguments.</para>
                            </listitem>
                        </varlistentry>

                        <varlistentry>
                            <term>e</term>
                            <listitem>
                                <para>Print the exit reason.</para>
                            </listitem>
                        </varlistentry>

                        <varlistentry>
                            <term>i</term>
                            <listitem>
                                <para>Print rate processing details.</para>
                            </listitem>
                        </varlistentry>

                        <varlistentry>
                            <term>s</term>
                            <listitem>
                                <para>Print the first server-ID.</para>
                            </listitem>
                        </varlistentry>

                        <varlistentry>
                            <term>t</term>
                            <listitem>
                                <para>When finished, print timers of all successful exchanges.</para>
                            </listitem>
                        </varlistentry>

                        <varlistentry>
                            <term>T</term>
                            <listitem>
                                <para>When finished, print templates</para>
                            </listitem>
                        </varlistentry>
                    </variablelist>
                </listitem>

            </varlistentry>

        </variablelist>

        <refsect2>
            <title>DHCPv4-Only Options</title>
            <para>
                The following options only apply for DHCPv4 (i.e. when
                <option>-4</option> is given).
            </para>

            <variablelist>
                <varlistentry>
                    <term><option>-B</option></term>
                    <listitem>
                        <para>
                            Force broadcast handling.
                        </para>
                    </listitem>
                </varlistentry>
            </variablelist>
        </refsect2>

        <refsect2>
            <title>DHCPv6-Only Options</title>
            <para>
                The following options only apply for DHCPv6 (i.e. when
                <option>-6</option> is given).
            </para>

            <variablelist>

                <varlistentry>
                    <term><option>-c</option></term>
                    <listitem>
                        <para>
                            Add a rapid commit option (exchanges will be
                            SOLICIT-ADVERTISE).
                        </para>
                    </listitem>
                </varlistentry>

                <varlistentry>
                    <term><option>-F <replaceable class="parameter">release-rate</replaceable></option></term>
                    <listitem>
                        <para>
                            Rate at which IPv6 RELEASE requests are
                            sent to a server. This value is only valid
                            when used in conjunction with the exchange
                            rate (given by <option>-r <replaceable
                            class="parameter">rate</replaceable></option>).
                            Furthermore the sum of this value and the
                            renew-rate (given by <option>-f <replaceable
                            class="parameter">rate</replaceable></option>)
                            must be equal to or less than the exchange rate.
                        </para>
                    </listitem>
                </varlistentry>

            </variablelist>
        </refsect2>

        <refsect2>
            <title>Template-Related Options</title>
            <para>
                The following options may only be used in conjunction with
                <option>-T</option> and control how <command>perfdhcp</command>
                modifies the template.  The options may be specified multiple
                times on the command line; each occurrence affects the
                corresponding template file (see "TEMPLATES" above).
            </para>

            <varlistentry>
                <term><option>-E <replaceable class="parameter">time-offset</replaceable></option></term>
                <listitem>
                    <para>
                        Offset of the (DHCPv4) secs field or (DHCPv6)
                        elapsed-time option in the (second i.e. REQUEST)
                        template and must be 0 or a positive integer:
                        a value of 0 disables this.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-I <replaceable class="parameter">ip-offset</replaceable></option></term>
                <listitem>
                    <para>
                        Offset of the (DHCPv4) IP address in the requested-IP
                        option / (DHCPv6) IA_NA option in the (second/request)
                        template.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-O <replaceable class="parameter">random-offset</replaceable></option></term>
                <listitem>
                    <para>
                        Offset of the last octet to
                        randomize in the template.  <replaceable
                        class="parameter">random-offset</replaceable> must be
                        an integer greater than 3.  The <option>-T</option>
                        switch must be given to use this option.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-S <replaceable class="parameter">srvid-offset</replaceable></option></term>
                <listitem>
                    <para>
                        Offset of the server-ID option in the
                        (second/request) template.  <replaceable
                        class="parameter">srvid-offset</replaceable> must
                        be a positive integer, and the switch can only be
                        used when the template option (<option>-T</option>)
                        is also given.
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term><option>-X <replaceable class="parameter">xid-offset</replaceable></option></term>
                <listitem>
                    <para>
                        Offset of the transaction ID (xid) in the template.
                        <replaceable class="parameter">xid-offset</replaceable>
                        must be a positive integer, and the switch can only
                        be used when the template option (<option>-T</option>)
                        is also given.
                    </para>
                </listitem>
            </varlistentry>
        </refsect2>

        <refsect2>
            <title>Options Controlling a Test</title>
            <para>
                The following options may only be used in conjunction with
                <option>-r</option> and control both the length of the test
                and the frequency of reports.
            </para>

            <variablelist>

                <varlistentry>
                    <term><option>-D <replaceable class="parameter">max-drop</replaceable></option></term>
                    <listitem>
                        <para>
                            Abort the test if more than <replaceable
                            class="parameter">max-drop</replaceable>
                            requests have been dropped.  Use <option>-D
                            0</option> to abort if even a single
                            request has been dropped.  If <replaceable
                            class="parameter">max-drop</replaceable> includes
                            the suffix '%', it specifies a maximum percentage
                            of requests that may be dropped before abort.
                            In this case, testing of the threshold begins after
                            10 requests have been expected to be received.
                        </para>
                    </listitem>
                </varlistentry>

                <varlistentry>
                    <term><option>-n <replaceable class="parameter">num-requests</replaceable></option></term>
                    <listitem>
                        <para>
                            Initiate <replaceable
                            class="parameter">num-request</replaceable>
                            transactions.  No report is generated until all
                            transactions have been initiated/waited-for,
                            after which a report is generated and the
                            program terminates.
                        </para>
                    </listitem>
                </varlistentry>

                <varlistentry>
                    <term><option>-p <replaceable class="parameter">test-period</replaceable></option></term>
                    <listitem>
                        <para>
                            Send requests for <replaceable
                            class="parameter">test-period</replaceable>,
                            which is specified in the same manner as
                            <option>-d</option>.  This can be used as an
                            alternative to <option>-n</option>, or both
                            options can be given, in which case the testing
                            is completed when either limit is reached.
                        </para>
                    </listitem>
                </varlistentry>

                <varlistentry>
                    <term><option>-t <replaceable class="parameter">interval</replaceable></option></term>
                    <listitem>
                        <para>
                            Sets the delay (in seconds) between two successive reports.
                        </para>
                    </listitem>
                </varlistentry>

            </variablelist>
        </refsect2>

        <refsect2>
            <title>Arguments</title>

            <variablelist>
                <varlistentry>
                    <term>server</term>
                    <listitem>
                        <para>
                            Server to test, specified as an IP address.
                            In the DHCPv6 case, the special name 'all' can be
                            used to refer to All_DHCP_Relay_Agents_and_Servers
                            (the multicast address FF02::1:2), or the special
                            name 'servers' to refer to All_DHCP_Servers (the
                            multicast address FF05::1:3).  The server is
                            mandatory except where the <option>-l</option>
                            option is given to specify an interface, in
                            which case it defaults to 'all'.
                        </para>
                    </listitem>
                </varlistentry>
            </variablelist>
        </refsect2>


    </refsect1>

    <refsect1>
        <title>ERRORS</title>

        <para>
            <command>perfdhcp</command> can report the following errors in the packet exchange:
        </para>

        <variablelist>
            <varlistentry>
                <term>tooshort</term>
                <listitem>
                    <para>A message was received that was too short.</para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term>orphans</term>
                <listitem>
                    <para>
                        Received a message which doesn't match one sent
                        to the server (i.e. it is a duplicate message, a
                        message that has arrived after an excessive delay,
                        or one that is just not recognized).
                    </para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term>locallimit</term>
                <listitem>
                    <para>Reached local system limits when sending a message.</para>
                </listitem>
            </varlistentry>
        </variablelist>

    </refsect1>

    <refsect1>
        <title>EXIT STATUS</title>

        <para>
            <command>perfdhcp</command> can exit with one of the following
            status codes:
        </para>

        <variablelist>
            <varlistentry>
                <term>0</term> <listitem>
                    <para>Success.</para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term>1</term>
                <listitem>
                    <para>General error.</para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term>2</term>
                <listitem>
                    <para>Error in command-line arguments.</para>
                </listitem>
            </varlistentry>

            <varlistentry>
                <term>3</term>
                <listitem>
                    <para>No general failures in operation, but one or more exchanges were unsuccessful.</para>
                </listitem>
            </varlistentry>
        </variablelist>

    </refsect1>

    <refsect1>
        <title>SEE ALSO</title>
        <para>
            <citerefentry><refentrytitle>dhcpd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
            <citerefentry><refentrytitle>kea-dhcp4</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
            <citerefentry><refentrytitle>kea-dhcp6</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
            <citetitle>Kea Administrator Guide</citetitle>.
<!--
see http://kea.isc.org/ticket/4077
            <citetitle>DHCP Performance Guide</citetitle>
-->

        </para>
    </refsect1>

<!--
    <refsect1>
        <title>HISTORY</title>
        <para>
            The <command>perfdhcp</command> tool was initially coded  by John DuBois, Francis Dupont and Marcin Siodelski of ISC.
        </para>
    </refsect1>
-->

</refentry>