The xfnts_monitor_start Method

The RGM calls the Monitor_start method on a node to start the fault monitor after a resource is started on the node. The xfnts_monitor_start method uses scds_pmf_start to start the monitor daemon under PMF.

The first call in xfnts_monitor_start is to scds_initialize, which performs some necessary house-keeping functions (see The scds_initialize Call and the scds_initialize(3HA) man page for details.

The xfnts_monitor_start method calls the mon_start method, which is defined in xfnts.c as follows.

Example 8–12

scds_syslog_debug(DBG_LEVEL_HIGH,
      "Calling Monitor_start method for resource <%s>.",
      scds_get_resource_name(scds_handle));

    /* Call scds_pmf_start and pass the name of the probe. */
   err = scds_pmf_start(scds_handle, SCDS_PMF_TYPE_MON,
       SCDS_PMF_SINGLE_INSTANCE, "xfnts_probe", 0);

   if (err != SCHA_ERR_NOERR) {
      scds_syslog(LOG_ERR,
          "Failed to start fault monitor.");
      return (1);
   }

   scds_syslog(LOG_INFO,
       "Started the fault monitor.");

   return (SCHA_ERR_NOERR); /* Successfully started Monitor */
}

Note the following about the call in svc_mon_start to the scds_pmf_start function.

• SCDS_PMF_TYPE_MON parameter identifies the program to start as a fault monitor—this method can also start a data service or some other type of application.

• The SCDS_PMF_SINGLE_INSTANCE parameter identifies this as a single-instance resource.

• The xfnts_probe parameter identifies the monitor daemon to start. The assumption is that the monitor daemon is in the same directory as the other callback programs.

• The final parameter, 0, specifies the child monitoring level—in this case, monitor the monitor daemon only.

Before it exits, the xfnts_monitor_start method calls scds_close to reclaim resources allocated by scds_initialize. See The scds_initialize Call and the scds_close(3HA) man page for details.