The xfonts_probe Main Loop

The xfonts_probe method implements a loop. Before implementing the loop, xfonts_probe

• Retrieves the network-address resources for the xfnts resource, as follows.

  ---

  Example 7-15

  
  

  	/* Get the ip addresses available for this resource */
  	if (scds_get_netaddr_list(scds_handle, &netaddr)) {
  		scds_syslog(LOG_ERR,
  		    "No network address resource in resource group.");
  		scds_close(&scds_handle);
  		return (1);
  	}
  
  	/* Return an error if there are no network resources */
  	if (netaddr == NULL || netaddr->num_netaddrs == 0) {
  		scds_syslog(LOG_ERR,
  		    "No network address resource in resource group.");
  		return (1);
  	}

  ---

• Calls scds_fm_sleep and passes the value of Thorough_probe_interval as the timeout value. The probe sleeps for the value of Thorough_probe_interval between probes.

  ---

  Example 7-16

  
  

  	timeout = scds_get_ext_probe_timeout(scds_handle);
  
  	for (;;) {
    
  		/*
  		 * sleep for a duration of thorough_probe_interval between
  		 *  successive probes.
  		 */
  		(void) scds_fm_sleep(scds_handle,
  		    scds_get_rs_thorough_probe_interval(scds_handle));

  ---

The xfnts_probe method implements the loop as follows.

Example 7-17

		for (ip = 0; ip < netaddr->num_netaddrs; ip++) {
			/*
			 * Grab the hostname and port on which the
			 * health has to be monitored.
			 */
			hostname = netaddr->netaddrs[ip].hostname;
			port = netaddr->netaddrs[ip].port_proto.port;
			/*
			 * HA-XFS supports only one port and
			 * hence obtain the port value from the
			 * first entry in the array of ports.
			 */
			ht1 = gethrtime(); /* Latch probe start time */
			scds_syslog(LOG_INFO, "Probing the service on "
			    "port: %d.", port);

			probe_result =
			svc_probe(scds_handle, hostname, port, timeout);

			/*
			 * Update service probe history,
			 * take action if necessary.
			 * Latch probe end time.
			 */
			ht2 = gethrtime();

			/* Convert to milliseconds */
			dt = (ulong_t)((ht2 - ht1) / 1e6);

			/*
			 * Compute failure history and take
			 * action if needed
			 */
			(void) scds_fm_action(scds_handle,
			    probe_result, (long)dt);
		}	/* Each net resource */
	} 	/* Keep probing forever */

The svc_probe function implements the probe logic. The return value from svc_probe is passed to scds_fm_action, which determines whether to restart the application, failover the resource group, or do nothing.