Index for Section 8

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caad(8)
NAME
  caad - Cluster Application Availability (CAA) daemon

SYNOPSIS
  /usr/sbin/caad [-0] [-1] [-2]

PARAMETER
  These parameters are used by CAA start and stop scripts only and should not
  be used when invoking caad using the command line.

  [-0]
      The daemon checks the state specified in the registry for each
      application resource on the cluster member and sets the resource state
      to OFFLINE. The daemon also checks the state of application resources
      for any other cluster members that are down at the time the daemon is
      started. This parameter should only be used by the init scripts at boot
      time.

  [-1]
      Used at startup to notify another running daemon to start application
      resources marked for restart in the binary CAA registry database. The
      daemon invoked with this parameter exits immediately after
      communicating with the running daemon.  This parameter should only be
      used by the init scripts at boot time.

  [-2]
      Used at cluster shutdown by clu_shutdown.	 The daemon sets a flag in
      the CAA registry database for each running application resource for the
      application to be started at next boot.

DESCRIPTION
  The CAA daemon (caad) monitors CAA resources and keeps CAA-managed
  applications highly available by starting, stopping, relocating and
  restarting application resources when failure conditions occur.  The daemon
  is an asynchronous, event-driven process that is started automatically when
  the system transitions to boot level 3.  It works in conjunction with the
  CAA user interface.  Do not stop the CAA daemon or the monitoring and
  management of CAA-managed applications will be disrupted.  This could
  jeopardize the availability of CAA-managed applications within the cluster.

  A resource profile describes a resource's failover criteria and relocation
  requirements.	 An administrator creates a resource profile for each
  resource to be monitored by the CAA daemon. The resource profile can be
  created for a network resource, tape resource, media changer resource,  or
  an application resource. Resource profiles are stored in the
  /var/cluster/caa/profile directory.

  For CAA-managed applications, the resource profile specifies values that
  describe how the caad daemon manages the application. This includes, the
  placement policy, required resources, hosting members, and other
  properties. The profile also specifies the action script that is used to
  start, stop, and check the application.

  The information in the profile is added to the CAA registry database when a
  resource is registered. The CAA daemon can only monitor and manage
  registered resources.

  Resource monitor files are loaded by the CAA daemon to enable checking on
  the state of a particular type of resource. Each resource type has a
  seperate resource monitor. Resource monitors are located in the directory
  /var/cluster/caa/monitors.

  See caa_profile(8) and caa(4) for more information on resource profiles.

  Each cluster member runs an instance of the CAA daemon.  These instances
  run autonomously, but communicate to share cluster and resource state
  information.

  Upon startup of the cluster system each CAA daemon reads from the registry
  database. The CAA daemon determines after reading the registry database the
  last state of the cluster and all registered available resources when the
  node failed or was shut down.

  For all registered application resources not currently running, the CAA
  daemon attempts to start these resources and begins monitoring all other
  types of resources.  How an application resource is started is determined
  by the start section of the resource's action script.

  Each application resource in the CAA subsystem is under the direct control
  of the cluster member currently running.  If under any circumstances, the
  resource is no longer available due to a member going down, all remaining
  CAA daemons in the CAA subsystem arbitrate to take control of the
  application.

  The caad daemon logs information into the EVM event management system. See
  EVM(5) for more information on viewing information in EVM.

EXIT VALUES
  The following exit values are returned:

  0   Successful completion

  non-zero
      A failure has occurred.

SEE ALSO
  Commands: caa_stat(1), caa_profile(8), caa_register(8), caa_relocate(8),
  caa_start(8),caa_stop(8), caa_unregister(8)

  File:	 caa(4)

  TruCluster Server Cluster Administration

Index for Section 8

Alphabetical listing for C

Top of page