failover-pair (nrcmd)                           failover-pair (nrcmd)


NAME
    failover-pair - configures a DHCP failover relationship

SYNOPSIS
    failover-pair <name> create <main-cluster/address>
                                <backup-cluster/address>
                                [<attribute>=<value> ...]
                                [addMatch [<vpn>/]<address/mask>]

    failover-pair <name> delete 
    failover-pair list
    failover-pair listnames
    failover-pair <name> show

    failover-pair <name> get <attribute>
    failover-pair <name> set <attribute>=<value> [<attribute>=<value> ...]
    failover-pair <name> unset <attribute>

    failover-pair <name> addMatch [<vpn>/]<address/mask>
    failover-pair <name> removeMatch [<vpn>/]<subnet/mask>
    failover-pair <name> listMatches

    failover-pair <name> sync <update | complete | exact> 
                         [<main-to-backup | backup-to-main>]

DESCRIPTION
    The failover-pair command lets you define and manage the failover
    relationship between a main and backup server.
    
    Either the main and backup clusters or the main and backup server
    IP addresses can be specified with the create command. If the 
    main-server and backup-server addresses are set, the cluster addresses 
    will only be used for synchronization of the server configuration.
    The referenced clusters must be configured with appropriate connection 
    credentials for the sync command to be successful.
        
EXAMPLES

STATUS

SEE ALSO
    cluster
    
PROPERTIES
  Attributes:

    backup[3] (AT_OID, Optional, default: <none>)
        Identifies the cluster that contains the backup server for
        a failover pair.

    backup-pct[19] (AT_PERCENT, Optional, default: 10%)
        Controls the percentage of available addresses that the main
        server sends to the backup server.  Set this value
        on the main server.  If it is set on a backup server, it is
        ignored (to enable copying of configurations).
        Unless you explicitly set this value on a scope and you disable
        load balancing, the value set here becomes the default value.

    backup-server[18] (AT_IPADDR, Optional, default: <none>)
        Controls the IP address used for the failover protocol on the
        backup server. If this value is unset, the address specified
        for the backup cluster is used. Cisco recommends setting
        this attribute only if the server is configured with
        different interfaces for configuration management and clients
        requests. Always configure the failover protocol with the
        interface used to serve clients.

    dynamic-bootp-backup-pct[28] (AT_PERCENT, Optional, default: <none>)
        Determines the percentage of available addresses that the
        main server sends to the backup server for scopes on which dynamic
        BOOTP is enabled.  If defined, it must be defined on
        the main server.  If it is defined in a backup server, it is
        ignored (to enable copying of configurations).  If it is not
        defined at all or the value is 0, the "backup-pct" is
        used instead.  This parameter is separate from "backup-pct"
        because if dynamic BOOTP is enabled on a scope, a server
        will never, even in PARTNER-DOWN state, grant leases on
        addresses that are available to the other server because
        they can never safely be assumed to be available again.
        The MCLT has no meaning for dynamic BOOTP leases.

    failover[20] (AT_BOOL, Optional, default: true)
        Enables failover configuration. If you disable this attribute,
        you turn off failover on attached subnets without changing
        configuration fundamentals.

    load-balancing[30] (AT_BOOL, Optional, default: disabled)
        Determines whether load balancing (RFC 3074) is enabled on a failover
        pair. The default is disabled. When enabled, the backup-pct is
        ignored and the main and backup server evenly split the client
        load and available leases for all scopes in the failover
        relationship (that is, as if backup-pct were configured at 50%).

    main[2] (AT_OID, Optional, default: <none>)
        Identifies the cluster with the main server for a failover pair.

    main-server[17] (AT_IPADDR, Optional, default: <none>)
        Controls the IP address used for the failover protocol on the
        main server. If this value is unset, the address specified
        for the main cluster is used. Cisco recommends setting
        this attribute only if the server is configured with
        different interfaces for configuration management and clients
        requests. Always configure the failover protocol with the
        interface used to serve clients.

    mclt[21] (AT_TIME, Optional, default: 60m)
        Sets the maximum client lead time in seconds. This attribute
        controls how far ahead of the backup server that you can make
        the client lease expiration. You must define this value on both
        the main and backup servers, and make sure the value is
        identical on both servers.

    name[1] (AT_STRING, Required, default: <none>)
        Names a failover pair.

    persist-lease-data-on-partner-ack[26] (AT_BOOL, Optional, default: true)
        Controls when the main server updates its database. Normally,
        the main server updates its database when the backup server
        ACKs it with what the backup knows.  Disabling this capability
        speeds up the main server, but after a restart the main server
        is out of sync with what the backup knows, and may offer all
        clients one lease period with a renew time of the current time
        plus the MCLT.

    poll-lease-hist-interval[8] (AT_RANGETIME, Optional, default: <none>)
        Specifies how often to collect lease history from the DHCP
        server for this cluster. If set to 0, no poll occurs.

    poll-lease-hist-offset[14] (AT_RANGETIME, Optional, default: <none>)
        Provides a fixed time of day for lease history polling.
        This time is interpreted as a time of day offset, with 0 being
        12 midnight, provided the polling interval is less than 24 hours,
        and the offset value is less than the polling interval. If the
        offset value is greater than the polling interval, or the
        interval is greater than 24 hours, the offset will be ignored.
        The scheduler for polling will ensure that the first polling
        event occurs at the offset time. For example, if you set the
        interval to 4 hours and the offset to 2am, the polling would
        occur at 2am, 6am, 10am, 2pm, 6pm and 10pm.

    poll-lease-hist-retry[9] (AT_RANGEINT(0-4), Optional, default: <none>)
        Specifies how often to retry if the server fails to poll
        the data.

    poll-lease-hist-server-first[10] (AT_ENUMINT(), Optional, default: mainserver)
        Specifies which server to poll first:
            0  main server
            1  backup server

    poll-subnet-util-interval[5] (AT_RANGETIME, Optional, default: <none>)
        Specifies how often to collect the subnet utilization data
        from DHCP server for this cluster. If set to 0, no poll
        occurs.

    poll-subnet-util-offset[15] (AT_RANGETIME, Optional, default: <none>)
        Provides a fixed time of day for subnet utilization polling.
        This time is interpreted as a time of day offset, with 0 being
        12 midnight, provided the polling interval is less than 24 hours,
        and the offset value is less than the polling interval. If the
        offset value is greater than the polling interval, or the
        interval is greater than 24 hours, the offset will be ignored.
        The scheduler for polling will ensure that the first polling
        event occurs at the offset time. For example, if you set the
        interval to 4 hours and the offset to 2am, the polling would
        occur at 2am, 6am, 10am, 2pm, 6pm and 10pm.

    poll-subnet-util-retry[6] (AT_RANGEINT(0-4), Optional, default: <none>)
        Specifies how often to retry if the server fails to poll
        the data.

    poll-subnet-util-server-first[7] (AT_ENUMINT(), Optional, default: mainserver)
        Specifies which server to poll first:
            0  main server
            1  backup server

    safe-period[24] (AT_TIME, Optional, default: 24h)
        Controls the safe period, in seconds.  It does not have to be
        the same on both main and backup servers.  It only has meaning
        if use-safe-period is enabled.  Define this attribute on the
        main server.  If it is defined on a backup server, it is ignored
        (to enable copying of configurations).

    scopetemplate[16] (AT_OID, Optional, default: <none>)
        Associates a scope template with a specified failover pair.

    use-safe-period[23] (AT_BOOL, Optional, default: disabled)
        Controls whether a server can enter PARTNER-DOWN state without
        an operator command. If disabled, a server never enters
        PARTNER-DOWN  without an operator command.
        Define this attribute on the main server.  If it is defined
        on a backup server, it is ignored (to enable copying of
        configurations).

