dscontrol highavailability

You can control high availability functions with the dscontrol highavailability command.

Syntax

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>>-dscontrol--highavailability--+-backup--+-add--+-primary-+--+-auto---+-+--port-+-><
                                |         |      '-backup--'  '-manual-' |       |   
                                |         '-delete-----------------------'       |   
                                +-heartbeat--+-add--srcaddress--dstaddress-+-----+   
                                |            '-delete--address-------------'     |   
                                +-reach--+-add----+--address---------------------+   
                                |        '-delete-'                              |   
                                +-status-----------------------------------------+   
                                '-takeover--+---------+--------------------------'   
                                            '-address-'                              

Parameters

backup
Specify information for either the primary or backup machine.
  • add
    Defines and runs the high availability functions for this machine.
    • primary

      Identifies the Dispatcher machine that has a primary role.

    • backup

      Identifies the Dispatcher machine that has a backup role.

    • auto

      Specifies an automatic recovery strategy, in which the primary machine will resume routing packets as soon as it comes back into service.

    • manual

      Specifies a manual recovery strategy, in which the primary machine does not resume routing packets until the administrator issues a takeover command.

  • delete

    Removes this machine from high availability, so that it will no longer be used as a backup or primary machine.

  • port

    An unused TCP port on both machines, to be used by Dispatcher for its heartbeat messages. The port must be the same for both the primary and backup machines.

heartbeat
Defines a communication session between the primary and backup Dispatcher machines.
  • add
    Tell the source Dispatcher the address of its partner (destination address).
    • source_address

      Source address. The address (IP or symbolic) of this Dispatcher machine.

    • destination_address

      Destination address. The address (IP or symbolic) of the other Dispatcher machine.

    The source_address and destination_address must be the NFAs of the machines for at least one heartbeat pair.
  • delete address

    Removes the address pair from the heartbeat information. You can specify either the destination or source address of the heartbeat pair. The address (IP or symbolic) of either the destination or the source.

reach
Add or delete target address for the primary and backup Dispatchers, the reach advisor sends out pings from both the backup and the primary Dispatchers to determine how reachable their targets are.
  • add address

    Adds a target address for the reach advisor. address is the IP address, format or symbolic, of the target node.

  • delete address

    Removes a target address from the reach advisor. address is the IP address, format or symbolic, of the target node.

Avoid trouble Avoid trouble: When configuring the reach target, you must also start the reach advisor. The reach advisor starts automatically when you use the dscontrol manager reach command.gotcha
status
Return a report on high availability. Machines are identified as having one of three status conditions or states:
  • Active: A given machine (either a primary, backup, or both) is routing packets.
  • Standby: A given machine (either a primary, backup, or both) is not routing packets; it is monitoring the state of an active Dispatcher.
  • Idle: A given machine is routing packets, and is not trying to establish contact with its partner Dispatcher.
takeover
Simple high availability configuration (role of the Dispatcher machines are either primary or backup).
Takeover instructs a standby Dispatcher to become active and to begin routing packets. This will force the currently active Dispatcher to become standby. The takeover command must be issued on the standby machine and works only when the strategy is manual. The substate must be synchronized.
  • address

    The takeover address value is optional. It should only be used when the role of the machine is both primary and backup (mutual high availability configuration). The address specified is the NFA of the Dispatcher machine which normally routes this cluster’s traffic. When there is a takeover of both clusters, specify the Dispatcher’s own NFA address.

Note:
  • The roles of the machines (primary and backup) do not change. Only their relative status (active or standby) changes.
  • There are three possible takeover scripts, which are goActive, goStandby, and goInOp. See Scripts to run with high availability for more information on these scripts.

Samples

Reference topic    

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Last updated: April 16, 2014 11:59 AM EDT
File name: rcmd_dscontrolha.html