dhcp (nrcmd)							dhcp (nrcmd)


NAME
    dhcp - Configures and controls the DHCP server

SYNOPSIS
    dhcp disable <attribute>
    dhcp enable <attribute>
    
    dhcp get <attribute>
    dhcp set <attribute>=<value> [<attribute>=<value> ...]
    dhcp unset <attribute>
    dhcp show

    dhcp getStats [[all | server [,] failover [,] dhcpv6] [total | sample]]
    dhcp resetStats
    dhcp getScopeCount [FailoverPair <name> | vpn <name> | all]
    dhcp getPrefixCount [vpn <name> |all]

    dhcp attachExtension <extension-point> <extension-name> [sequence number]
    dhcp detachExtension <extension-point> [sequence number]
    dhcp listExtensions

    dhcp setPartnerDown <partner-server-name> [<date>]
    dhcp getRelatedServers [column-separator=<string>]

    dhcp updateSms [all]
    dhcp serverLogs show
    dhcp serverLogs nlogs=<nlogs> logsize=<logsize>

    dhcp limitationList <ipaddr> [<limitation-id>] show

DESCRIPTION
    The dhcp command lets you configure the DHCP server in a cluster. 
 
     dhcp getStats [[all | server [,] failover [,] dhcpv6] [total | sample]]
     dhcp resetStats
       The getStats command retrieves statistics from a running DHCP
       server. You can supply one or more specific categories of 
       statistics counters, or the keyword all to retrieve all supported
       categories. If collection of sample counters is enabled in the 
       server, you can retrieve the most recent sample counters instead
       of the running totals by specifying sample after the categories. 
       The resetStats command resets the running totals counters.

    dhcp attachExtension <extension-point> <extension-name> [sequence number]
    dhcp detachExtension <extension-point> [sequence number]
    dhcp listExtensions
       Use the commands attachExtension, detachExtension,
       and listExtensions to configure the extensions points in the 
       server. 
       You can associate multiple extensions with each extension
       point, and each executes in the order specified by the sequence 
       number used when the attachment was made.  If no sequence number
       is used with attachExtension and detachExtension, it defaults 
       to 1.  If multiple extensions are configured for a given point, 
       listExtensions shows the sequence numbers associated with each.  
       Sequence numbers must be in the range 1-32.

       The available extension points are:
  Attributes:

    check-lease-acceptable[7] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point comes immediately after the server has
        determined if it thinks that the current lease is acceptable for
        this client.  The extension can examine the results of that
        operation, and can cause the routine to return different results
        if desired.  It should be used with extreme care, because
        incorrect use can cause the server to loop endlessly.

    environment-destructor[11] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point is called to allow the extension to clean
        up any internal context it might have created and stored in the
        environment dictionary before the environment dictionary is
        deleted. Only the environment dictionary is available.

    generate-lease[10] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point is called whenever a new lease is being
        generated for a DHCPv6 client. The request and response
        dictionary are both available. It can be used to generate the
        address or prefix to be delegated to the client.

    lease-state-change[9] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point is called whenever a lease changes state.
        It has a response dictionary, and sometimes a request dictionary.
        It can be used to track lease state changes so that leases that
        are transitioning from the leased to some other state can be
        caught, since they are not typically accompanied by DHCP client
        packets.

    post-class-lookup[8] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point comes immediately after the server has
        determined the client-class of an incoming DHCP packet by
        evaluating the expression configured in the client-class-lookup-id.

    post-client-lookup[4] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        Examines the results of the entire client-class processing operation,
        and takes action based on those results.  The usual actions to take
        are to rewrite some of the results, or to drop the packet.
        This would also be a place for an extension to place some data
        items in the environment dictionary in order to affect the
        processing of some extension running at the pre-packet-encode
        extension point (where it might load different options into the
        response packet or take other actions).

    post-packet-decode[1] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        Displays the first extension point encountered when a request
        arrives.  It immediately follows the decoding of the input packet,
        and precedes any processing on the data in the packet.  The
        primary activity for an extension at this point is to read
        information out of an input packet and do something with it.
        Typically, that action might be to re-write the input packet in
        some way.

    post-packet-encode[13] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        Allows an extension to examine the raw packet and alter the packet
        before it is sent to the client. Network Registrar calls this
        extension point after a response packet is encoded but before it is
        sent to the client.
        Note: If the packet is altered, it only changes what the
        client received; the server does not pick up any of the
        packet changes in the information it retains about the client.

    post-send-packet[5] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point exists so  that information about the
        request and response can be used to update an external process or
        database.

    pre-client-lookup[3] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point only runs for a request if the client-class
        processing as been enabled for the server.  The purpose of this
        extension point is to allow an extension to perform any or
        all of the following:
        1.  Modify the client that is looked up during client-class
            processing.
        2.  Specify individual data items to override any data items
            found from client entry or the client-class it specifies.
        3.  Instruct the server to skip the client lookup altogether.
            In this case, the only client data that will be used is that
            specified in #2, above.
        4.  Drop the packet.

    pre-dns-add-forward[6] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        This extension point exists to choose the name and affect the DNS
        retires during update operations.  It may get called multiple times
        for a single DNS update operation.  It has only an environment
        dictionary available.

    pre-packet-decode[12] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        Allows an extension to examine a raw packet and alter it before
        decoding and processing. This extension point is called after a
        packet is received but before it is decoded.
        Note: As the packet has yet to be decoded, most request
        dictionary data items are unavailable.

    pre-packet-encode[2] (AT_NAMEREF(ScriptConfig), Optional, default: <none>)
        Displays the extension point used to rewrite information in the
        response packet about to be sent to the user.  This extension point
        comes after the response packet is ready to be encoded into a
        packet to be sent to the DHCP client.  Typically, options could
        be added at this extension point to the packet.  The packet
        can also be dropped at this point, but the DHCP server will
        already have recorded its values in its internal database.


       The attachExtension command sets the specified extension point (and
       optional sequence position) to call the named extension.  If the 
       extension point is already configured (for a given sequence position)
       to call an extension, Network Registrar overwrites it with the new
       value.
    
       The detachExtension command removes any extension configuration from
       the specified extension point and sequence number.
    
       The listExtensions command shows the current configurations for
       each extension point.
    
       You can put the DHCP server into import mode by enabling the
       import-mode feature and then restarting the server. You take
       the server out of import-mode by disabling the feature and restarting
       the server. You can use import mode to exclude all DHCP lease
       requests except for the specially tagged ones that come from the
       CLI during lease import (see the import command).


    dhcp setPartnerDown <partner-server-name> [<date>]
       The dhcp setPartnerDown command notifies the DHCP server that one of
       its safe failover partner servers is down.  The date specified
       represents a time equal to or later than the last known time the
       partner server could have been operational.  If no date is specified,
       the current time is used.  The time value should be entered using
       the local time of the nrcmd process.  Formats for the date are:

       -<num><value>
          where <num> is a decimal number and <value> is one of 's', 'm',
          'h', 'd', 'w', in which 's' is seconds, 'm' is minutes, 'h' is
          hours, 'd' is days and 'w' is weeks.
 
       <month> <day> <hour>:<minute>[:<second>] <year>
          where <month> is the name or first three letters of the name of
          the month, <hour> is the hour on a 24- hour clock, and <year> is
          the fully-specified year or a two-digit representation in which
          98 = 1998, 99 = 1999 and all other two digit values XX = 20XX.

    dhcp getRelatedServers [column-separator=<string>]
       The dhcp getRelatedServers command displays a table with the following
       information for each associated safe failover, DNS or LDAP server:

          Type
             Main, Backup, DNS or LDAP

          Name
             DNS host name

          Address
             IP Address in dotted octet format

          Communications
             OK or INTERRUPTED

          Requests
             Number of outstanding requests

          <cluster-name> State
             Failover state of this server

          Partner State
             Failover state of partner

    
    dhcp updateSms [all]
        The dhcp updateSms command initiates SMS processing. To send all
        leases to SMS, use the argument all; otherwise, only the new leases
        activated since the last time the command ran successfully are sent.
        To run this command, turn on sms-network-discovery and set 
        sms-library-path. The command returns an error if sms-network-discovery is 
        not turned on or if it is unable to load SMS library or if the optional
        argument string is invalid, otherwise it returns success to indicate SMS 
        processing started successfully.
 
    
    dhcp serverLogs show
       The serverLogs show command displays the number of log files and the 
       maximum size for each file.
    
        The serverLogs command allows setting the two server logging parameters,
        nlogs and logsize.  Either or both may be specified in the command, and
        changes will only occur to the one(s) specified.  When setting logsize,
        the value may be suffixed with K or M to signify units of thousands or
        millions.  Note that in order for these changes to take effect you must
        save the changes and restart the server Agent. 
    
        dhcp serverLogs nlogs=6 logsize=500K
        dhcp serverLogs logsize=5M
    
       
    dhcp getScopeCount [FailoverPair <name> | vpn <name> | all]
       The getScopeCount command displays the scopes, networks, and VPNs
       for the current VPN, all VPNs, a specific VPN, or a failover pair.
       The getPrefixCount command displays the prefixes, links, and VPNs
       for the current VPN, all VPNs, or a specific VPN.

       If the ip-history feature is enabled, you should trim
       records from the history database  to reclaim disk space. 
       Each history record has a binding end time. Periodically,
       the DHCP server examines the lease history records, and deletes
       any records for bindings which ended at least ip-history-max-age
       in the past.

    dhcp limitationList <ipaddr> [<limitation-id>] show
       Lists DHCP clients and leases that are associated by a common 
       limitation-id for the client (see the client command). Use this
	 command when a DHCP client is denied service because the number of
       existing clients with a common limitation-id equals the allowed
       limitation-count, as set for a policy (see the policy command).
       It then determines which existing clients with that limitation-id 
       have active leases.
 
       If you specify both the ipaddr and limitation-id arguments, the ipaddr 
       determines the network in which to search, and does not have to be an 
       actual IP address that the DHCP server could allocate. In this case, the
       limitation-id must be a blob in nn:nn:nn format (such as 01:02:03) or a 
       string in string format. If you omit the limitation-id, the ipaddr must
       be the IP address of a currently active lease, and the limitation-id used 
       for the command will be the one associated with that lease.     

       If you want to determine the existing clients and leases using up
       the limitation-count for a particular limitation-id because the following
       message appeared in the DHCP server log:
    
   	   Warning Server 0 05646 Could not add Client MAC: 
	   '1,6,01:02:03:04:0c:03'  with limitation-id: 01:02:03
	   using Lease: 10.0.0.23, already 3 Clients with that id.  
	   No over-limit client class specified! Dropping packet!

       Use the lease specified in "...  using Lease 10.0.0.23" as
       the <ipaddr>, and the limitation-id specified in "...  with
       limitation-id 01:02:03" as the <limitation-id>:

   	   nrcmd> dhcp limitationList 10.0.0.23 01:02:03 show

       The result would be a list of 3 leases with the client's MAC
       address, the client last transaction time, and the client's host name.

EXAMPLES

STATUS

SEE ALSO
    server
    
PROPERTIES
  Attributes:

    activity-summary-interval[137] (AT_TIME, Optional, default: 5m)
        Sets the time that elapses between activity summary log
        messages. You must also enable the activity-summary setting
        in log-settings.

    addr-blocks-default-selection-tags[164] (AT_ARRAY(AT_STRING), Optional, default: <none>)
        Associates a default selection tag (or list of tags) with incoming
        subnet-allocation requests that do not contain any subnet name
        data.

    addr-blocks-use-client-affinity[162] (AT_BOOL, Optional, default: true)
        Controls whether the DHCP server allocates subnets to clients
        using address-blocks that the clients have already used.
        If you set this attribute to false, the server allocates subnets
        from any suitable block (based on other selection data in client
        messages.

    addr-blocks-use-lan-segments[161] (AT_BOOL, Optional, default: false)
        Controls whether DHCP subnet-allocation uses the lan-segment
        attribute when it is configured on address-blocks.

    addr-blocks-use-selection-tags[163] (AT_BOOL, Optional, default: true)
        Controls whether the server compares subnet name data on an
        incoming subnet-allocation request with the selection tag of each
        address-block.  A block is only considered if the two match.

    atul-port[212] (AT_RANGEINT(1-65535), Optional, default: 7543)
        If configured, enables the DHCP server to listen for incoming
        ATUL queries on this UDP port.

    atul-support[217] (AT_BOOL, Optional, default: off)
        Enables DHCP support for the ATUL query protocol. The atul-port
        parameter configures the port number to use to listen for
        ATUL queries.

    client-cache-count[154] (AT_INT, Optional, default: 1000)
        Specifies the maximum number of clients in the client cache.
        The DHCP server allocates the amount at startup and frees
        it at shutdown. If you set the value to 0, you disable client
        caching and the server must use persistent storage to process a
        DHCPREQUEST.

    client-cache-ttl[155] (AT_TIME, Optional, default: 10s)
        Sets the maximum time-to-live in seconds for a client in
        cache. The DHCP server discards the entries in memory after
        this period.

    client-class[24] (AT_BOOL, Optional, default: disabled)
        Controls how the DHCP server uses the client and client-class
        configuration objects to affect request processing. Default is
        false (disabled).

    client-class-lookup-id[166] (AT_EXPR, Optional, default: <none>)
        Specifies the expression used to determine a client-class solely
        on data contained in an incoming DHCP client request.
        The expression must return a string with the name of a currently
        configured client-class, otherwise it must return the string
        '<none>'. Any return that is not a string containing the name
        of a currently configured client-class or '<none>' is considered
        an error.

    cnr-5-0-upgraded[146] (AT_DATE, Optional, default: <none>)
        Indicates whether the DHCP server was upgraded from 3.5 to 5.0.
        Read-only.

    collect-addr-util-duration[192] (AT_RANGETIME, Optional, default: 0)
        
        Sets the maximum period, in hours, that the DHCP server
        maintains address utilization data.
        To disable collecting address utilization data, unset
        this attribute or give it a value of 0.
        Use this attribute, with the collect-addr-util-interval
        attribute, to determine the frequency that the server
        uses to take snapshots of the data and to set the length of
        time the DHCP server maintains the data. Together these attributes
        have an impact on memory usage because each snapshot of data is
        68 bytes.
        For example, if you have 10 scopes and you set
        collect-addr-util-duration is set to 24h and
        collect-addr-util-interval to 1h, memory used by the DHCP
        server to maintain address utilization data is 24 times 68 bytes
        for each scope; that is, 10x24x68 or 16KB.

    collect-addr-util-interval[193] (AT_RANGETIME, Optional, default: 15m)
        Sets the frequency, in minutes or hours, that the DHCP
        server uses to take snapshot views of address utilization data.
        If collect-addr-util-duration is not configured, or set
        to 0, the DHCP server ignores the collect-addr-util-interval.
        Use this attribute, with the collect-addr-util-duration
        attribute, to determine the frequency that the server uses to
        take snapshots of the data and the length of time the DHCP server
        maintains the data. Together these attributes affect memory
        usage because each snapshot of data is 68 bytes.
        For example, if you have 10 scopes and you set
        collect-addr-util-duration to 24h and collect-addr-util-interval
        to 1h, memory used by the DHCP erver to maintain address
        utilization data is 24 times 68 bytesfor each scope; that is,
        10x24x68 or 16KB.

    collect-performance-statistics[131] (AT_BOOL, Optional, default: false)
        Controls whether the DHCP server collects statistics for
        performance monitoring.

    collect-sample-counters[200] (AT_BOOL, Optional, default: disabled)
        Controls whether the DHCP server collects activity statistics
        counters independently of the log-settings attribute flag.
        If false, this attribute is disabled.
        If true, this attribute enables collecting activity
        statistics.
        Note: These activity statistics counters are also enabled,
        if you enable 'activity-summary'
        logging is enabled (see 'log-settings').

    default-free-address-config[225] (AT_NAMEREF(AddrTrapConfig), Optional, default: <none>)
        Specifies the default SNMP free-address trap configuration object
        for the server. All scopes that are not individually configured
        use this default free-address value.

    defer-lease-extensions[58] (AT_BOOL, Optional, default: true)
        Determines whether the DHCP server can defer extending leases
        to their full lease expiration time.
        If enabled (true), the DHCP server can defer extending the lease
        expiration time. Rather than give the client the full configured
        lease time, the server instead gives the client the remaining 
        time on the existing lease, improving server performance and 
        throughput. The DHCP server typically defers extending the lease
        if the client renews early; that is, before the client's lease 
        renewal time (T1) elapses.
        If enabled, the DHCP server can save committing the lease to 
        disk and updating its failover partner with an extended lease 
        expiration time.
        If disabled, the DHCP server always attempts to extend the 
        lease expiration time. However, there may be conditions 
        that prevent the server from extending the lease for the full 
        configured lease time; for example, failover protocol restrictions.

    delete-orphaned-leases[152] (AT_BOOL, Optional, default: false)
        Controls how the DHCP server handles orphaned leases.
        Default is false (disabled).
        A lease is orphaned if:
        --It does not match a range or reservation in a configured scope, or
        --If it appears in the lease state database with a VPN ID that does
          not match a VPN in the database.
        If this is attribute is true, the server deletes orphaned leases
        when the server next reloads. This ensures that the lease state
        database has no old, unconfigured leases in it, but it also may
        cause the total loss of lease state information due to a mistake
        in configuration.
        If this attribute is false, the server ignores the entries in
        the lease state database. If the lease was orphaned due to a
        configuration mistake, then when you when you correct the
        mistake, the DHCP server can use the lease.
        Whether true or false, the server cannot use the lease.

    delete-orphaned-subnets[156] (AT_BOOL, Optional, default: false)
        Controls how the DHCP server handles information about an
        orphaned subnet; that is, whether it keeps the entry in its
        database or deletes it. Default is false (disable).
        As the DHCP server starts up, it tries to locate the
        parent VPN and DHCP address block of each DHCP subnet. If a
        subnet refers to a VPN that is no longer configured, or if
        the server cannot locate a parent DHCP address block that
        contains the subnet, the server uses this attribute
        to decide.

    dns-timeout[18] (AT_INT, Required, default: 60000)
        Controls the number of milliseconds that the DHCP server waits
        for a response before retrying dynamic DNS requests.

    docsis-version-id-missing[100] (AT_STRING, Optional, default: <none>)
        Sets the string value (maximum 255 characters) to substitute
        for the %@docsis-vers% variable in the policy command boot-
        file attribute. No default.
        DOCSIS devices must provide their version id
        (for example, "docsis1.0") in the vendor-class-id option.
        The server substitutes the DOCSIS version id as the
        value of the boot-file option. If the vendor
        class-id option is missing, or is not syntactically correct,
        the server uses the docsis-version-id-missing attribute
        for the boot-file option.
        This substitution occurs if the DHCP request packet does not
        contain a vendor-class-id option or the option does not contain
        a DOCSIS version ID.

    drop-old-packets[136] (AT_INT, Optional, default: 4)
        Sets the time, in seconds, that a packet can age and still be
        processed.
        The server attempts to read as many packets as possible from
        the UDP input queue, and then process them quickly.  If the
        server is very busy, it can sometimes become flooded with
        packets. This could delay processing some packets.
        In the DHCP protocol, however, some clients automatically
        retry packets that have not been processed in a few seconds
        --so allowing the server to process packets that are
        older than a small number of seconds.  This can increase
        congestion without providing any real value for the clients.
        The drop-old-packets parameter is the number of seconds that
        a packet can age and still be processed by the DHCP server.
        If a packet is more than the value of drop-old-packets old
        when processed by the DHCP server, the server drops the packet.

    drop-packet-on-extension-failure[41] (AT_BOOL, Optional, default: enabled)
        Causes the server to drop a packet (if possible) when it
        encounters an extension failure. Default is true (enable).

    enhanced-sample-counters[231] (AT_BOOL, Optional, default: enabled)
        Enables collection of enhanced statistics counters by the DHCP
        server, which are then available with DHCP server statistics.
        The enhanced counters provide more detailed information, but
        cost the server some performance to maintain. Currently, this
        enables collecting milliseconds ACK/Reply latencies (instead
        of second based) and scope aggregation data (even if not
        explicitly configured).

    equal-priority-most-available[191] (AT_BOOL, Optional, default: disabled)
        Controls address allocation among scopes in the same network.
        This attribute determines how the DHCP server allocates an
        address to a new client when multiple scopes have the same
        nonzero allocation priority. Default is false (disable).
        If disabled, the server uses the scope with the fewest available
        addresses to allocate an address to a new client (if not in a
        limitation list).
        If enabled, the server uses the scope with the most available
        addresses to allocate an address to a new client
        (if not in a limitation list).
        In either case, if a client is in a limitation list,
        among those scopes of the same priority, the one that contains
        other clients in the same list is always used.

    expression-configuration-trace-level[182] (AT_INT, Optional, default: 2)
        Sets the trace level to use when configuring DHCP expressions.
        Default is 2 (failure retry).
        The range is from 0 through 6, with 0 being the lowest amount
        of tracing and 6 the highest:
           0  No additional tracing
           1  No additional tracing
           2  Failure retry
           3  Function definitions
           4  Function arguments
           5  Variable lookups and literal details
           6  Everything
        Setting a high expression-configuration-trace-level imposes no
        performance penalty, since expressions are configured only
        when you restart the server.

    expression-trace-level[167] (AT_INT, Optional, default: 2)
        Sets the trace level to use when executing DHCP expressions.
        ptional, default 2.
        The range is from 0 through 6, with 0 being no tracing and 6 the
        highest amount of tracing:
        0-No tracing
        1-Failures, including those protected by (try ...)
        2-Total failure retries (with trace level = 6 for retry)
        3-Function calls and returns
        4-Function arguments evaluated
        5-Print function arguments
        6-Datatype conversions (everything)
        Setting this attribute to any level other than 0, 1, or 2
        imposes a considerable performance penalty.
        The setting of 1 only traces when there is a failure in an
        expression. The default setting of 2 re-executes
        evaluating an expression that fails at the outermost level
        with the expression-trace-level=10 for the duration of the
        re-execution, to provide maximum debugging assistance.

    extension-trace-level[40] (AT_INT, Optional, default: 0)
        Sets the value of the extension trace level for every
        request object. Default is 0.
        The range is from 0 through 3, with 0 being very little tracing
        and 3 the highest amount of tracing.

    failover-bulking[143] (AT_BOOL, Optional, default: true)
        With failover enabled, controls whether a failover BIND update
        (BNDUPD) contains multiple lease state updates. Default true
        (enable).
        This attribute affects only the lease state updates that a DHCP
        client generates.

    failover-poll-interval[74] (AT_TIME, Optional, default: 15s)
        With failover enabled, controls the space of time, in seconds,
        that elapses between polls of failover partners to confirm
        network connectivity. Default is 15s.

    failover-poll-timeout[75] (AT_TIME, Optional, default: 60s)
        With failover enabled, defines the space of time, in seconds,
        after which a poll between partners times out. Default is 60s.
        This attribute signals that the partners cannot communicate
        due to lost network connectivity. The partners then change their
        operational states appropriately.

    failover-recover[71] (AT_DATE, Optional, default: none)
        
        With failover enabled, sets the time at which the server
        is initialized and goes into RECOVER state. No default.
        If failover-recover is non-zero, and the server has no
        record of a previous failover state in its stable storage,
        then the server assumes that it was previously operational
        but lost all of its stable storage.
        The time value in the failover-recover parameter represents
        a time equal to or later than the last known time the server
        could have been operational.  The server attempts to refresh
        its information from its failover partner by entering RECOVER
        state and requesting a complete update of all binding
        information.
        Time values for this attribute can be in hours (for example,
        -2h two hours ago) or month day hour:minute[:second] year.
        Use the local time of the nrcmd process.
        Formats for the date are:
        -<num><value>
          where <num> is a decimal number and <value> is one of 's', 'm',
          'h', 'd', 'w', in which 's' is seconds, 'm' is minutes, 'h' is
          hours, 'd' is days and 'w' is weeks.
        <month> <day> <hour>:<minute>[:<second>] <year>
          where <month> is the name or first three letters of the name of
          the month, <hour> is the hour on a 24- hour clock, and <year> is
          the fully-specified year or a two-digit representation in which
          98 = 1998, 99 = 1999 and all other two digit values XX = 20XX.

    force-dns-updates[110] (AT_BOOL, Optional, default: false)
        
        Controls whether the DHCP server retries a DNS update
        whenever a client renews its lease, even if it appears
        to the server that the update was already completed
        successfully. Default is false (disable).
        This attribute uses one of the following values:
           forward DnsUpdateConfig object (if configured)
           reverse DnsUpdateConfig object (if configured)
           the default (or where appropriate the server configured
           value or default value).

    get-subnet-mask-from-policy[108] (AT_BOOL, Optional, default: false)
        Controls whether the DHCP server searches all relevant
        policies for a subnet mask option to construct a response
        to a client. Default is false (disable).
        Normally, the DHCP server retains the subnet mask configured
        in the scope containing the base being granted to the DHCP
        client.

    ha-dns-failover-timeout[222] (AT_RANGEINT(30-120), Optional, default: 30)
        
        Sets the maximum time period in seconds that the DHCP server
        waits for replies from a DNS server before failing over to its
        partner. Default is 30s.
        To use this attribute, first configure your DHCP server to
        perform HA DNS updates.
        If DHCP is configured for HA-DNS updates, dns-timeout parameters
        are set to fit max-dns-retries within ha-dns-failover-timeout.
        For example, with a default ha-dns-failover-timeout value of
        30 seconds and and max-dns-retries of 3, dns-timeout is set to
        6 seconds, so that after 3 retry attempts and an
        ha-dns-failover-timeout, the DHCP server failovers. The DHCP
        server uses a minimum limit value for a dns-timeout of 2 seconds
        and dns-retries of 1.

    hardware-unicast[37] (AT_BOOL, Optional, default: enabled)
        Controls whether the DHCP server sends unicast rather
        than broadcast responses when a client indicates that it can
        accept a unicast.
        Note: This attribute is only available on these
        operating systems: Solaris, Windows 2000, and Windows NT.

    ignore-cisco-options[198] (AT_NLIST(AT_STRING), Optional, default: <none>)
        Skips processing the Cisco-specific DHCP options specified
        by name in the comma-separated list.  No default.
        Allowable option names are vpn-id (185), cisco-vpn-id (221),
        and subnet-alloc (220). Use this attribute only if
        clients use the options for other purposes.

    ignore-icmp-errors[57] (AT_BOOL, Optional, default: enabled)
        Controls how the DHCP server handles ICMP ECHO (ping-before-
        offer) requests. Default is true (enable).
        If you enable this attribute and configure the DHCP server to
        to send ICMP ECHO requests, the server makes unavailable any
        address for which it receives an ECHO reply within its
        configured timeout period.
        If you disable this attribute, the DHCP server also treats
        ICMP DEST_UNREACHABLE and TTL_EXPIRED error messages that it
        receives after sending ICMP ECHO requests as grounds for making
        an address unavailable.

    ignore-requests-for-other-servers[145] (AT_BOOL, Optional, default: <none>)
        
        Controls whether to prevent the normal DHCP server
        response to client requests for other servers.  No
        default.
        Normally, if the DHCP server detects a client requesting a lease
        from another server for an address that this server is
        configured to control, it sets the lease to unavailable. Some
        clients, however, might send request packets with bad server ID
        options--rather than packets actually directed to other
        servers--that the server wrongly interprets as an unavailable
        address. Enabling this attribute prevents this.

    import-mode[25] (AT_BOOL, Optional, default: disabled)
        
        Controls whether the DHCP server recognizes only packets
        generated from the import leases command, ignoring all
        others. Default is false (disable).
        Use this attribute to update your DHCP server, preventing
        clients from receiving addresses during this period.

    inhibit-busy-optimization[135] (AT_BOOL, Optional, default: false)
        
        Controls whether the server uses optimization to recover from
        periods of congestion. Default false (disable).
        By default, the DHCP server determines that it is heavily loaded
        when the number of request packets reaches two-thirds of the
        total allocated. The server logs a message and attempts to
        recover from the congestion by performing several optimizations.
        For example, it relaxes the requirement to keep the clients
        last transaction time updated to the granularity specified by
        the last-transaction-time-granularity attribute.
        When the number of request packets drops to one-third of the
        total allocated, the server logs a message and returns to
        normal operation. If you enable the inhibit-busy-optimization
        attribute, the server does not use the optimizations or log the
        messages when it gets congested.

    initial-environment-dictionary[185] (AT_STRING, Optional, default: <none>)
        Contains attribute-value pairs that initialize all environment
        dictionaries used within the DHCP server.  Use these attribute-value
        pairs to configure extensions or expressions without having to
        re-write the executable code in the extension or expression.
        The string must have the format:
        "attribute1=value1,attribute2=value2, ... ,attributen=valuen"

    ip-history[157] (AT_BOOL, Optional, default: disabled)
        Enables the lease history database. Default is false (disable).

    ip-history-detail[197] (AT_BOOL, Optional, default: false)
        Controls whether to record detailed data for the IP
        history database. Default is false (disable).

    ip-history-max-age[195] (AT_TIME, Optional, default: 4w)
        If ip-history is enabled, determines how long IP records are
        kept in the database. Default is 4w.
        The server accumulates database records over time as lease
        bindings change. The ip-history-max-age attribute establishes
        a limit on the age of thehistory records kept in the database.
        The server periodically examines the lease history records,
        establishes an age threshold based on this parameter, and
        deletes any records that represent bindings that end before
        the threshold. The history records are trimmed by default once
        a day, at 3:00 a.m. local time.

    last-transaction-time-granularity[59] (AT_TIME, Optional, default: 60s)
        Sets the time, in seconds, to guarantee that the last
        transaction time is accurate. Default is 60s.
        Do not set this lower than the default of 60 seconds. For
        optimal performance, set it to a value that is greater than half
        of your lease interval.
        By default the server maintains an accurate record of the time
        when it last interacted with a DHCP client concerning a given
        lease.  This setting provides a control on how accurate that time
        is guaranteed to be.  A setting of 300 seconds, for instance,
        would allow the server to avoid database updates whose sole
        purpose is to update a last transaction time that is less than 5
        minutes in the past.

    ldap-mode[51] (AT_ENUMINT(), Optional, default: <none>)
        Determines the preference for using LDAP servers if
        multiple LDAP servers are configured. No default.
        This attribute has two possible values:
           1  round-robin-The DHCP server ignores LDAP server
              preferences. It treats all LDAP servers (those configured
              to handle client queries and those configured to accept
              lease-state updates) equally.
           2  failover-The DHCP server uses the active LDAP server with
              the lowest preference. If the preferred server loses its
              connection or fails, the DHCP server uses the next LDAP
              server in preference order. The DHCP server uses servers
              with equal preference in round-robin order.

    log-settings[27] (AT_FLAGSINT(), Optional, default: default,incoming-packets,missing-options)
        Determines which events to log in the log files. Default flags are
        default, incoming-packets, and missing-options.
        Logging additional detail about events can help analyze a problem.
        However, leaving detailed logging enabled for a long period
        can fill up the log files.
        Possible flags are:
          default
            The default gives a low level of logging in several parts of
            the DHCP server.  If you unconfigure the default, even this
            logging will not appear.
          missing-options
            This setting (on by default) will cause a message to be logged
            whenever an option requested by a DHCP client has not been
            configured in a policy and therefore cannot be supplied by the
            DHCP server.
          incoming-packets
            This setting (on by default) will cause a single line message
            to be logged for every incoming packet.  This is especially
            useful when initially configuring a DHCP server or a BOOTP
            relay, in that an immediate positive indication exists that
            the DHCP server is receiving packets.
          incoming-packet-detail
            This setting will cause the contents of every DHCP packet
            received by the DHCP server to be interpreted in a human
            readable way and printed in the log file.  This enables the
            built-in DHCP packet sniffer for input packets.  The log files
            will fill up (and turn over) very rapidly when this setting is
            enabled.  This setting also causes a significant performance
            impact on the DHCP server and should not be left enabled as a
            matter of course.
          outgoing-packet-detail
            This setting will cause the contents of every DHCP packet
            transmitted by the DHCP server to be interpreted in a human
            readable way and printed in the log file.  This enables the
            built-in DHCP packet sniffer for output packets.  The log files
            will fill up (and turn over) very rapidly when this setting is
            enabled.  This setting also causes a significant performance
            impact on the DHCP server and should not be left enabled as a
            matter of course.
          client-detail
            This setting will cause a single line to be logged at the
            conclusion of every client-class client lookup operation.  This
            line will show the composite of the data found for the client
            as well as the data that found in the client's client-class.
            It is useful when setting up a client-class configuration and
            for debugging problems in client-class processing.
          client-criteria-processing
            This setting will cause a log message to be output whenever a
            scope is examined to find an available lease or whenever a
            scope is examined to determine if a lease is still acceptable
            for a client who already has one.  It can be very useful when
            configuring or debugging client-class scope criteria
            processing.  It causes moderate amount of information to be
            logged and should not be left enabled as a matter of course.
          unknown-criteria
            This setting will cause a single line log message to appear
            whenever a client entry is found which specifies selection
            criteria that is not found in any scope appropriate for that
            client's current network location.
          dns-update-detail
            This setting causes the server to log a message as it sends
            each dns update and as it receives replies to update messages.
          ldap-query-detail
            This setting will cause log messages to appear whenever the
            dhcp server initiates a query to LDAP server, receives response
            and retrieves result or error messages.
          ldap-update-detail
            This setting will cause log messages to appear whenever the
            dhcp server initiates an update lease state to LDAP server,
            receives response and retrieves result or error messages.
          ldap-create-detail
            This setting will cause log messages to appear whenever the
            dhcp server initiates an lease state entry create to LDAP
            server, receives response and retrieves result or error
            messages.
          leasequery
            This setting will cause log messages to appear when leasequery
            packets are processed without internal errors and result in
            an ACK or a NAK.
          dropped-waiting-packets
            If the value of max-waiting-packets is non-zero packets may
            be dropped if the queue length for any IP address exceeds the
            value of max-waiting-packets.  If dropped-waiting-packets
            is set, the server will log a message whenever it drops a
            waiting packet from the queue for an IP address.
          no-success-messages
            This setting will cause the single line message that is
            normally logged for every successful outgoing DHCP response
            packet to not appear.  It affects logging only for successful
            outgoing DHCP response packets.
          no-dropped-dhcp-packets
            This setting will cause a single line message normally logged
            for every DHCP packet that is dropped due to DHCP
            configuration to not appear.  (See no-invalid-packets for
            messages associated with packets dropped because they are
            invalid.)
          no-dropped-bootp-packets
            This setting will cause the single line message normally
            logged for every BOOTP packet that is dropped to not appear.
          no-failover-activity
            This setting will cause normal activity and some warning
            messages logged for failover to not appear.  Serious error
            log messages will continue to appear independent of this
            log-setting.
          activity-summary
            This setting will cause a summary message to appear every 5
            minutes.  It is useful when many of the no-xxx log settings
            are enabled, to give some idea of the activity in the server
            without imposing the load required for a log message
            corresponding to each DHCP message.  The time period for
            these messages can be configured with the DHCP server
            property activity-summary-interval.
          no-invalid-packets
            This setting will cause a single line message normally logged
            for every DHCP packet that is dropped due being invalid to
            not appear.  (See no-dropped-dhcp-packets for messages
            associated with packets dropped due to DHCP server
            configuration.)
          no-reduce-logging-when-busy
            Normally, the DHCP server will reduce logging when it becomes
            very busy (i.e., when it has used over 2/3 of the available
            receive buffers (itself a configurable value)).  It will set
            no-success-messages, no-dropped-dhcp-packets,
            no-dropped-bootp-packets, no-failover-activity,
            no-invalid-packets, and clear everything else except
            activity-summary.  If no-reduce-logging-activity is set, then
            the server will not do this.  It will restore the previous
            settings when the server becomes unbusy (i.e., when it has
            used only 1/3 of the available receive buffers).
          no-timeouts
            This setting will cause messages associated with timeout
            of leases or offers not to appear in the log file.
          minimal-config-info
            This setting will reduce the number of configuration messages
            printed when the server starts or reloads.  In particular,
            it will not log a message for every scope.
          no-failover-conflict
            This setting will cause conflicts between failover partners
            to not be logged.
          atul-detail
            This setting causes the server to log messages when ATUL
            messages are received and processed.
          v6-lease-detail
            This setting causes the server to log individual messages
            regarding DHCPv6 leasing activity (in addition to or in
            place of a single message per client transaction depending
            on no-success-messages, or client timeout event depending on
            no-timeouts).

    mac-address-only[22] (AT_BOOL, Optional, default: disabled)
        
        Controls whether the DHCP server uses the clients MAC
        address as the only client identifier. The standard behavior,
        as specified in RFC 2132, is to use the client-id option (if it
        is present) as the unique client identifier. Default is false
        (disable).
        CAUTION: Use this attribute with care. When enabled, it
        precludes a MAC address from getting multiple IP addresses per
        network. It forces the server to use a Client-Identifier (CID)
        created from the MAC address instead of the RFC described
        client-id contained in the request. This can preclude newer
        devices that take multiple IP addresses. Enabling, or later
        disabling, this attribute can also have an operational impact.
        Clients that originally obtain addresses through a client-id
        cannot renew them once they are assigned attributes based on
        a MAC address.

    map-radius-class[189] (AT_ENUMINT(), Optional, default: 0)
        Controls how to map the radius attribute, if present,
        in the client request relay-agent option:
           0  none             Ignores the radius class name default
           1  map-as-tag       Maps the radius class to selection-tags
           2  map-as-class     Maps the radius class  directly to a
                               client-class name
           3  append-to-tags   Appends the radius class to the
                               selection-tags

    map-radius-pool-name[218] (AT_ENUMINT(), Optional, default: 0)
        Controls use of the radius framed-pool attribute, if present,
        in a client relay-agent option.
           0  none             Ignores the framed-pool attribute
           1  map-as-tag       Maps the framed-pool attribute to
                               selection-tags
           2  map-as-class     Maps framed-pool attribute directly to a
                               client-class name
           3  append-to-tags   Appends the user-class-id to the
                               selection-tags

    map-user-class-id[123] (AT_ENUMINT(), Optional, default: 0)
        Controls how the server uses the user-class-id option. Values are:
           0  none             Ignores the user class-id(default)
           1  map-as-tag       Maps the user-class-id to selection-tags
           2  map-as-class     Maps user-class-id directly to a
                               client-class name
           3  append-to-tags   Appends the user-class-id to the
                               selection-tags

    max-client-leases[220] (AT_RANGEINT(1-65535), Optional, default: 50)
        Sets the maximum number of leases, regardless of state or whether
        reserved or not, that the server can associate with a DHCPv6
        client. A DHCPv6 lease is always associated with a client; if it
        is not, it is deleted.
        This setting is to prevent a client from using lots of leases
        (such as by issuing many requests with different IAID values). It
        is not intended to limit the number of active leases a client may
        have.
        While 1 can be configured as the minimum for backwards
        compatibility, the server uses a minium of 2 to allow for a
        client that usually only has a single lease to be renumbered or
        moved to a different prefix on the link.
        This limit is not applied when existing leases are loaded from
        the lease state database during server start-up.

    max-dhcp-requests[4] (AT_INT, Required, default: 500)
        Controls the number of buffers that the DHCP server allocates
        for receiving client requests.
        When you enable failover, allocate at least 150 buffers. Up to
        1500 buffers might be reasonable for high capacity
        installations.
        Caution: Increasing the number of buffers can degrade
        performance. Cisco recommends using the default value
        in most situations. When buffer size exceeds capacity, a burst
        of DHCP activity can clog the server with requests that become
        stale before they are processed. This increases the processing
        load and might severely degrade performance as clients try to
        obtain a new lease. A lower buffer setting throttles requests
        and avoids wasted processing on requests that would otherwise be
        stale.
        When using LDAP client lookups, buffers should not exceed the
        LDAP lookup queue size defined by the total number of LDAP
        connections and the maximum number of requests allowed for each
        connection. Set the LDAP queue size to match the LDAP servers
        capacity to service client lookups.

    max-dhcp-responses[5] (AT_INT, Required, default: 1000)
        Controls the number of buffers that the DHCP server allocates
        for responses to client requests. The server ignores this
        value if max-dhcp-requests is higher, or other configuration
        options such as failover require that the value be set higher
        than configured.

    max-dns-renaming-retries[17] (AT_INT, Required, default: 3)
        Controls the number of times that the DHCP server can attempt
        adding a host into DNS, even if the DHCP server detects that the
        hostname is already present in DNS.  The DHCP server attempts
        to modify the hostname in order to resolve a conflict on each
        failed update.

    max-dns-retries[16] (AT_INT, Required, default: 3)
        Controls the number of times that the DHCP server can try to
        send dynamic updates to a DNS server.

    max-dns-ttl[19] (AT_INT, Required, default: 86400)
        Sets the time to live (TTL) ceiling, in seconds, for DNS records
        added through dynamic updates. When the DHCP server adds a DNS
        record, it uses a TTL of the minimum of either this ceiling or one
        third the lease time.

    max-ping-packets[6] (AT_INT, Optional, default: 500)
        Sets the number of buffers the server allocated for sending and
        receiving ICMP ping messages. See the scope 'ping-clients'
        command.

    max-waiting-packets[116] (AT_INT, Optional, default: 6)
        Sets the maximum number of packets that can wait for a
        particular IP address.
        The server queues only the most recently received n packets
        (of an address) for processing. If an additional packet
        associated with that address arrives and n packets are already
        queued, the server drops the oldest packet and queues the new
        one. It also drops duplicate packets (whose XID, client ID, and
        MAC address are the same as one already queued).
        A value of 0 indicates that there is no maximum queue length,
        and all packets are processed.
        Dropped packets are logged if the log setting
        dropped-waiting-packets is set. It is off by default.

    mcd-blobs-per-bulk-read[138] (AT_RANGEINT(1-2500), Optional, default: <none>)
        Determines the number of binary large objects (blobs) in a bulk
        read. Default 256.  Range, 1 to 2500.
        Use this attribute to tune DHCP start and reload times.
        Generally, a higher value will result in faster server start and
        reload time, at the cost of using more memory.

    min-dns-ttl[229] (AT_TIME, Optional, default: 10m)
        Minimum value for time to live (TTL) in seconds, for DNS records
        added through dynamic updates.  When the DHCP server adds a DNS
        record, the TTL value will be min-dns-ttl if one third the lease
        time is less than the min-dns-ttl value.

    multicast-addresses[211] (AT_NLIST(AT_IP6ADDR), Optional, default: ff02::1:2,ff05::1:3)
        Controls the default multicast addresses that are enabled
        on interfaces. The address ff02::1:2 is required if any
        DHCPv6 clients are directly connected to the link associated
        with an interface. The address ff05::1:3 is the default
        multicast address that relay agents use to relay DHCPv6
        requests.

    one-lease-per-client[23] (AT_ENUMINT(), Optional, default: disabled)
        Controls whether the DHCP server releases other leases a client
        might have on other LAN segments on this server.
           0   disabled
           1   last-client-preferred
           2   first-client-preferred
        Within one LAN segment, the DHCP server never allocates more
        than one DHCPv4 address to a single client. Across multiple
        independent network LAN segments, however, a single client
        might have one address allocated on several networks.
        In an enterprise environment this might happen when a laptop
        user travels from building to building, causing no particular
        problems. In a service provider context, this might happen when
        an unapproved user attempts to clone the MAC address of a
        legitimate subscriber, causing a theft of service.
        The one-lease-per-client feature limits a single client to one
        lease over all of the networks configured on the DHCP server.
        This limit only affects a client's ability to have concurrent
        leases to different IP addresses on more than one network at
        a time on the DHCP server.
        In the last-client-preferred approach, the client with the most
        recent lease is given preference, and any other leases held by
        the same client are released.
        In the first-client-preferred approach, the first lease that a
        particular client receives from the DHCP server is the only
        lease that client is allowed.  In the event that the client
        moves, the first lease must be made available (perhaps by a
        force-available command or by letting it expire) before the
        client is allowed to lease another IP address on a different
        network.
        Caution: Use the first-client-preferred approach with great
        care, since manual intervention might be required to ensure
        proper operation.
        Both forms of one-lease-per-client require additional bookkeeping
        overhead beyond that normally done in the DHCP server.

    priority-address-allocation[190] (AT_BOOL, Optional, default: disabled)
        Controls address allocation among scopes in the same network and
        within an individual scope as well.
        When enabled, any scope without an explicit setting for
        allocation-priority is configured with an allocation-priority
        equal to the network number of the scope.  Similarly, any scope
        without an explicit setting for allocate-first-available
        is considered enabled.
        Explicit settings for either of these scope attributes override
        the priority-address-allocation set for that scope.
        This attribute gives the administrator a way to change address
        allocation in a server wide manner without having to separately
        configure each scope.

    return-client-fqdn-if-asked[115] (AT_BOOL, Optional, default: true)
        Controls whether the system returns the client FQDN option
        in the outgoing packet to the client if the incoming packet
        contains the FQDN option. Default false (disable).
        If true (enable), the option flags are always set to 0x3
        and the RCODE1 and RCODE2 to 255. Any string contained in the
        incoming packet is returned, even if the use-client-fqdn
        attribute is disabled and regardless of the actual FQDN.

    save-vendor-class-id[101] (AT_BOOL, Optional, default: false)
        Determines whether to store the vendor=class-id, as
        furnished in a dhcp request option 60, as part of the lease
        record in either ldap, mcd or both.

    skip-client-lookup[125] (AT_BOOL, Optional, default: false)
        Determines whether the DHCP server looks up the client entry
        in the database to do client-class processing. This value
        can be examined as well as changed in a script at the
        pre-client-lookup extension point. Default false
        (disable).
        If true, the server skips the client entry.

    sms-lease-interval[120] (AT_INT, Optional, default: 1100)
        Sets the amount of time, in milliseconds, that the DHCP server
        waits between sending addresses to the System Management Server
        (SMS) when executing updateSms command.

    sms-library-path[118] (AT_STRING, Optional, default: <none>)
        Overrides the internal default value for the SMS.dll.  Default
        is an empty string.
        If the string is empty, the system defaults to the internal
        server default of smsrsgen.dll.
        If the string is not empty, its value overrides the internal
        SMS library name, smsrsgen.dll. If the system path does not include
        the location of the SMS dll, you should provide the absolute path
        of the dll.

    sms-network-discovery[117] (AT_INT, Optional, default: 0)
        Determines whether the DHCP server generates SMS network
        discovery records.
        If this attribute is set to 0, you disable SMS network
        discovery. If it is set to 1, you enable discovery.
        Use this attribute in conjunction with the dhcp updateSMS
        command.

    sms-site-code[119] (AT_STRING, Optional, default: <none>)
        Specifies the site code name of the SMS server that receives
        discovery records when you use the updateSMS keyword.
        For proper functioning, make sure that you initialize this
        attribute to the appropriate site code.
        The default value is an empty string, but this prohibits data
        discovery to complete successfully. So, you must provide the
        site code.

    synthesize-reverse-zone[186] (AT_BOOL, Optional, default: enabled)
        Controls whether the DHCP server automatically generates the
        name of the reverse zone (in-addr.arpa or ip6.arpa) that receives
        PTR records updates.  Default is true (enable).
        If true, you are not required to configure an explicit 
        dns-reverse-zone-name in the DNS update configuration. Instead, the
        DHCP server uses the IP address of each lease and the dns-host-bytes 
        attribute of the scope or the reverse-zone-prefix-length attribute 
        of the prefix to synthesize the reverse zone name for each update. 
        The server trims the specified host bytes from the low-order
        bytes of the address, and turns the remaining bytes into a zone
        name of the form '.b.a.in-addr.arpa.' The host-bytes
        low-order bytes of the address are used to form the hostname
        within that zone. Similarly, the prefix length is used to
        form the 'ip6.arpa' zone name, and the low-order bytes are used
        to form the hostname.

    traps-enabled[202] (AT_FLAGSINT(), Optional, default: <none>)
        Determines the traps that this server is configured to send.
           1  all
              Sends notifications for all server events.
           2  server-start
              Sends notifications whenever the server is started or
              reinitialized.
           3  server-stop
              Sends notifications whenever the server is stopped.
           4  free-address-low
              Sends notifications when the number of free IP addresses
              becomes less than or equal to the low threshold.
           5  free-address-high
              Sends notifications when the number of free IP addresses
              exceeds the high threshold after having previously
              triggered the free-address-low trap.
           6  dns-queue-size
              Sends notifications when the DHCP servers DNS queue
              fills and the DHCP server stops processing requests.
           7  other-server-down
              Sends notifications when another server (DHCP, DNS, or
              LDAP) stops responding to this DHCP server.
           8  other-server-up
              Sends notifications when another server (DHCP, DNS, or
              LDAP) responds after having been unresponsive.
           9  duplicate-address
              Sends notifications whenever a duplicate IP address is
              detected.
           10 address-conflict
              Sends notifications when an address conflict with another
              DHCP server is detected.
           11 failover-config-error
              Notifies when a configuration mismatch between DHCP
              failover partners occurs.
           12 free-address-low
              Sends notifications when the number of free IPv6 addresses
              becomes less than or equal to the low threshold.
           13 free-address-high
              Sends notifications when the number of free IPv6 addresses
              exceeds the high threshold after having previously
              triggered the free-address-low6 trap.
           14 duplicate-address6
              Sends notifications whenever a duplicate IPv6 address is
              detected.
           15 duplicate-prefix6
              Sends notifications whenever a duplicate prefix is
              detected.
        No default.

    trim-host-name[187] (AT_BOOL, Optional, default: enabled)
        Controls whether or not DHCP server trims the hostname string
        to the first period (or dot) character (used to update DDNS
        records and to return host-name-option to clients). Default,
        true (enable).
        If true, the hostname is truncated before the period.
        If false, the DHCP server retains the period characters in the
        hostname.

    update-dns-for-bootp[45] (AT_BOOL, Optional, default: enabled)
        If the server is replying to a BOOTP request, and is offering a
        lease from a Scope which is configured to perform DNS updates, it
        will check this property before beginning the DNS update. This
        feature allows an administrator to prevent DNS updates for BOOTP
        clients, while allowing updates for DHCP clients.

    upgrade-unavailable-timeout[183] (AT_TIME, Optional, default: 24h)
        Controls the time given to a lease in the database that has no
        expiration; that is, it became unavailable prior to
        installing Network Registrar. The DHCP server uses the
        upgrade-unavailable-timeout for the expiration time of the
        unavailable lease. Default is 86400 seconds (1 day).

    use-client-fqdn[113] (AT_BOOL, Optional, default: true)
        Controls whether the server examines the client-FQDN option
        for the hostname. Default is true (enable).
        If true, the server ignores any characters after the first dot (.)
        because the domain is determined from the scope.
        If false, the server does not determine the hostname using this.
        This is useful if the client is sending unexpected or junk
        characters.

    use-client-fqdn-first[111] (AT_BOOL, Optional, default: true)
        Controls whether the DHCP server looks at the client-FQDN option
        on incoming packets first, before looking at the 'hostname'
        option.  Default is true (enable).
        If true and the client-FQDN option specifies a hostname, the
        server uses that hostname.
        If the client-FQDN option is not present in the incoming packet,
        the server uses the hostname from the 'hostname' option.
        If false, the server also uses the hostname from the
        'hostname' option.

    use-dns-update-prereqs[150] (AT_BOOL, Optional, default: true)
        Controls whether the DHCP server adds prerequisites to DNS
        update messages.  Default true (enable).
        If true, the DHCP server includes prerequisites in DNS update
        messages to make sure the client is using the domain name,
        before it is updated with the current lease (IP
        address).
        If false, the DHCP server assumes the requesting client is
        entitled to the domain name.  In this case, it does not include
        prerequisites in the DNS update message, and associates the client
        lease with that domain name.
        Note: The DHCP server always adds prerequisites to the DNS
        update message while adding a new domain name record on behalf
        of a client acquiring a new lease and removing the domain name
        record when a client releases its lease or the lease expires.

    use-host-name[112] (AT_BOOL, Optional, default: true)
        Specifies whether the server looks at  the 'hostname' option
        for the hostname. Default is true (enable).
        If true, the server obtains the hostname from the 'hostname'
        option.
        If false, the server does not obtain the hostname from this
        option. This is useful if the client is sending unexpected or
        junk characters.

    use-ldap-client-data[44] (AT_BOOL, Optional, default: disabled)
        Controls whether the DHCP server attempts to read client-entry
        data using the configuration supplied by the 'ldap'
        command. Default is false (disable).

    v6-client-class-lookup-id[213] (AT_EXPR, Optional, default: <none>)
        Defines the expression used to assign a client-class based
        solely on data contained in an incoming DHCPv6 client request.
        No default.
        The expression must return a string that is the name of a
        currently configured client-class; otherwise, the expression
        must return the string '<none>'. Any return that is not a string
        containing the name of a currently configured client-class or
        '<none>' is considered an error.

    v6-default-free-address-config[237] (AT_NAMEREF(AddrTrapConfig), Optional, default: <none>)
        Specifies the default SNMP v6 free-address trap configuration object
        for the server. All Prefixes and Links that are not individually
        configured use this default free-address value.

    validate-client-name-as-mac[181] (AT_BOOL, Optional, default: false)
        Controls whether the Network Registrar user interfaces require
        that the name of client entries is valid MAC address (or the
        literal string 'default').  Default is false (disable).
        If true, the user interfaces convert the name to the canonical
        MAC address format: 1,6,xx:xx:xx:xx:xx:xx.  The DHCP server uses
        this as the default client entry lookup key.
        If false, the user interfaces allow creating client
        entries with arbitrary names, which could match the lookup
        keys generated from the client-lookup-id expression.

    vpn-communication[153] (AT_BOOL, Optional, default: true)
        Controls the ability of the DHCP server to communicate with
        clients that are on a different VPN from the server. Default
        is true (enable).
        If true, the server communicates with DHCP clients residing on
        a different VPN by using an enhanced DHCP Relay Agent capability.
        This enhanced DHCP Relay Agent capability is indicated by the
        appearance of the server-id-override sub-option in
        the relay agent information option (Option 82).

