poller.php

#!/usr/bin/env php
<?php
/*
 +-------------------------------------------------------------------------+
 | Copyright (C) 2004-2024 The Cacti Group                                 |
 |                                                                         |
 | This program is free software; you can redistribute it and/or           |
 | modify it under the terms of the GNU General Public License             |
 | as published by the Free Software Foundation; either version 2          |
 | of the License, or (at your option) any later version.                  |
 |                                                                         |
 | This program is distributed in the hope that it will be useful,         |
 | but WITHOUT ANY WARRANTY; without even the implied warranty of          |
 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the           |
 | GNU General Public License for more details.                            |
 +-------------------------------------------------------------------------+
 | Cacti: The Complete RRDtool-based Graphing Solution                     |
 +-------------------------------------------------------------------------+
 | This code is designed, written, and maintained by the Cacti Group. See  |
 | about.php and/or the AUTHORS file for specific developer information.   |
 +-------------------------------------------------------------------------+
 | http://www.cacti.net/                                                   |
 +-------------------------------------------------------------------------+
*/

if (function_exists('pcntl_async_signals')) {
	pcntl_async_signals(true);
} else {
	declare(ticks = 100);
}

ini_set('output_buffering', 'Off');

require(__DIR__ . '/include/cli_check.php');
require_once(CACTI_PATH_LIBRARY . '/poller.php');
require_once(CACTI_PATH_LIBRARY . '/data_query.php');
require_once(CACTI_PATH_LIBRARY . '/rrd.php');
require_once(CACTI_PATH_LIBRARY . '/dsstats.php');
require_once(CACTI_PATH_LIBRARY . '/dsdebug.php');
require_once(CACTI_PATH_LIBRARY . '/boost.php');
require_once(CACTI_PATH_LIBRARY . '/reports.php');
require_once(CACTI_PATH_LIBRARY . '/rrdcheck.php');

global $poller_db_cnn_id, $remote_db_cnn_id, $logged;

if ($config['poller_id'] > 1 && $config['connection'] == 'online') {
	$poller_db_cnn_id = $remote_db_cnn_id;
} else {
	$poller_db_cnn_id = false;
}

function sig_handler($signo) {
	global $poller_db_cnn_id;

	switch ($signo) {
		case SIGTERM:
		case SIGINT:
			cacti_log('WARNING: Cacti Master Poller process terminated by user', true, 'POLLER', POLLER_VERBOSITY_LOW);

			$running_processes = db_fetch_assoc('SELECT ' . SQL_NO_CACHE . ' *
				FROM poller_time
				WHERE end_time=\'0000-00-00 00:00:00\'', true, $poller_db_cnn_id);

			if (cacti_sizeof($running_processes)) {
				foreach ($running_processes as $process) {
					if (function_exists('posix_kill')) {
						cacti_log("WARNING: Termination poller process with pid '" . $process['pid'] . "'", true, 'POLLER', POLLER_VERBOSITY_LOW);
						posix_kill($process['pid'], SIGTERM);
					}
				}
			}

			db_execute('TRUNCATE TABLE poller_time', true, $poller_db_cnn_id);

			exit;

			break;

		default:
			// ignore all other signals
	}
}

// initialize some variables
$force     = false;
$debug     = false;
$mibs      = false;
$logged    = false;

// set the poller_id
$poller_id = $config['poller_id'];
$hostname  = php_uname('n');

// requires for remote poller stage out
chdir(__DIR__);

// process calling arguments
$parms = $_SERVER['argv'];
array_shift($parms);

if (cacti_sizeof($parms)) {
	foreach ($parms as $parameter) {
		if (strpos($parameter, '=')) {
			list($arg, $value) = explode('=', $parameter);
		} else {
			$arg   = $parameter;
			$value = '';
		}

		switch ($arg) {
			case '-p':
			case '--poller':
				$poller_id = $value;

				break;
			case '-d':
			case '--debug':
				$debug = true;

				break;
			case '--force':
				$force = true;

				break;
			case '--version':
			case '-V':
			case '-v':
				display_version();

				exit;
			case '-H':
			case '-h':
			case '--help':
				display_help();

				exit;

			default:
				print "ERROR: Invalid Argument: ($arg)\n\n";
				display_help();

				exit(1);
		}
	}
}

// catch upgrade case
if (!db_column_exists('poller', 'dbhost')) {
	cacti_log('Poller is upgrading from pre Cacti 1.0, exiting till upgraded.', false, 'POLLER');

	exit(0);
}

$phostname = db_fetch_cell_prepared('SELECT hostname
	FROM poller
	WHERE id = ?',
	array($poller_id), '', true, $poller_db_cnn_id);

// update the pollers hostname if it is blank, otherwise allow the user to edit it
if ($phostname == '' || $phostname == 'localhost' || $phostname == '127.0.0.1') {
	db_execute_prepared('UPDATE poller
		SET hostname = ?
		WHERE id = ?',
		array($hostname, $poller_id), true, $poller_db_cnn_id);
}

$dbhostname = db_fetch_cell_prepared('SELECT dbhost
	FROM poller
	WHERE id = ?',
	array($poller_id), '', true, $poller_db_cnn_id);

// update the database hostname based upon the entry
if ($dbhostname == '' || $dbhostname == 'localhost' || $dbhostname == '127.0.0.1') {
	if ($database_hostname != 'localhost' && $database_hostname != '127.0.0.1') {
		$hostname = $database_hostname;
	}

	db_execute_prepared('UPDATE poller
		SET dbhost = ?
		WHERE id = ?',
		array($hostname, $poller_id), true, $poller_db_cnn_id);
}

// if you have more than one poller, boost must be enabled
$total_pollers = db_fetch_cell('SELECT COUNT(*) FROM poller');

if ($total_pollers > 1) {
	set_config_option('boost_rrd_update_system_enable', 'on');
	set_config_option('boost_redirect', 'on');
}

// check to see if the poller is disabled
poller_enabled_check($poller_id);

// install signal handlers for UNIX only
if (function_exists('pcntl_signal')) {
	pcntl_signal(SIGTERM, 'sig_handler');
	pcntl_signal(SIGINT, 'sig_handler');
}

// record the start time
$poller_start    = microtime(true);
$overhead_time   = 0;
$current_time    = time();

poller_table_maintenance();

api_plugin_hook('poller_top');

// prime the poller_resource_cache for multiple pollers
if ($config['connection'] == 'online') {
	update_resource_cache($poller_id);
}

// get number of polling items from the database
$poller_interval = read_config_option('poller_interval');

// retrieve the last time the poller ran
$poller_lastrun  = read_config_option('poller_lastrun_' . $poller_id);

// is boost enabled
$boost_enabled   = read_config_option('boost_rrd_update_enable') == 'on' ? true:false;

// collect the system mibs every 4 hours
if ($poller_lastrun % 14440 < $current_time % 14440 || empty($poller_lastrun)) {
	$mibs = true;
}

// get the poller data
$poller = db_fetch_row_prepared('SELECT *
	FROM poller
	WHERE id = ?',
	array($poller_id), true, $poller_db_cnn_id);

// get the current cron interval from the database
$cron_interval = read_config_option('cron_interval');

if ($cron_interval != 60) {
	$cron_interval = 300;
}

// get max step.  If it's not equal to the poller
// interval, we have to force active profiles
// greater than 1.
$max_step = db_fetch_cell('SELECT MAX(dsp.step)
	FROM data_source_profiles AS dsp
	INNER JOIN data_template_data AS dtd
	ON dtd.data_source_profile_id = dsp.id');

// see if the user wishes to use process leveling
$process_leveling = read_config_option('process_leveling');

// retrieve the number of concurrent process settings
if (cacti_sizeof($poller)) {
	$concurrent_processes = $poller['processes'];
} else {
	$concurrent_processes = read_config_option('concurrent_processes');
}

if (!isset($concurrent_processes) || intval($concurrent_processes) < 1) {
	$concurrent_processes = 1;
}

// correct for possible poller output not empty occurrences
$ds_needing_fixes = db_fetch_assoc_prepared('SELECT local_data_id,
	MIN(rrd_next_step) AS next_step,
	COUNT(DISTINCT rrd_next_step) AS instances
	FROM poller_item
	WHERE poller_id = ?
	AND rrd_num > 1
	GROUP BY local_data_id
	HAVING instances > 1',
	array($poller_id));

if (cacti_sizeof($ds_needing_fixes)) {
	foreach ($ds_needing_fixes as $ds) {
		db_execute_prepared('UPDATE poller_item
			SET rrd_next_step = ?
			WHERE local_data_id = ?',
			array($ds['next_step'], $ds['local_data_id']));
	}
}

/**
 * shortcut some expensive logic in spine if possible the
 * order by snmp port is a rare thing to be needed and only
 * needs to occur if your are talking to more than one snmp
 * agent on a host.
 */
$total_ports = db_fetch_cell('SELECT COUNT(DISTINCT snmp_port)
	FROM poller_item
	WHERE snmp_port > 0');

set_config_option('total_snmp_ports', $total_ports);

/**
 * determine the number of active profiles to improve poller performance
 * under some circumstances.  Save this data for spine and cmd.php.
 * In the case where the $max_step does not equal the poller interval
 * we have to artificially set the $active_profiles > 1
 */
if ($poller_interval != $max_step) {
	$active_profiles = 2;
} elseif ($cron_interval == $poller_interval) {
	$active_profiles = db_fetch_cell('SELECT COUNT(DISTINCT data_source_profile_id)
		FROM data_template_data
		WHERE local_data_id > 0');
} else {
	$active_profiles = db_fetch_cell('SELECT COUNT(DISTINCT rrd_next_step) FROM poller_item');
}

set_config_option('active_profiles', $active_profiles);

/* assume a scheduled task of either 60 or 300 seconds */
if (!empty($poller_interval)) {
	$poller_runs = intval($cron_interval / $poller_interval);

	if ($active_profiles != 1) {
		$sql_where   = "WHERE rrd_next_step - $poller_interval <= 0 AND h.disabled = '' AND pi.poller_id = $poller_id";
	} else {
		$sql_where   = "WHERE pi.poller_id = $poller_id AND h.disabled = ''";
	}

	define('MAX_POLLER_RUNTIME', $poller_runs * $poller_interval - 2);
} else {
	$sql_where       = "WHERE pi.poller_id = $poller_id AND h.disabled = ''";

	$poller_runs     = 1;
	$poller_interval = 300;
	define('MAX_POLLER_RUNTIME', 298);
}

$num_polling_items = db_fetch_cell('SELECT ' . SQL_NO_CACHE . ' COUNT(*)
	FROM poller_item AS pi
	INNER JOIN host AS h
	ON h.id = pi.host_id ' . $sql_where);

if (isset($concurrent_processes) && $concurrent_processes > 1) {
	$items_perhost = array_rekey(
		db_fetch_assoc('SELECT ' . SQL_NO_CACHE . " host_id,
			COUNT(local_data_id) AS data_sources
			FROM poller_item AS pi
			INNER JOIN host AS h
			ON h.id = pi.host_id
			$sql_where
			GROUP BY host_id
			ORDER BY host_id"),
		'host_id', 'data_sources'
	);
}

if (isset($items_perhost) && cacti_sizeof($items_perhost)) {
	$items_per_process = floor($num_polling_items / $concurrent_processes);

	if ($items_per_process == 0) {
		$process_leveling = 'off';
	}
} else {
	$process_leveling = 'off';
}

// some text formatting for platform specific vocabulary
if ($config['cacti_server_os'] == 'unix') {
	$task_type = 'Cron';
} else {
	$task_type = 'Scheduled Task';
}

if ($debug) {
	$level = POLLER_VERBOSITY_NONE;
} else {
	$level = POLLER_VERBOSITY_MEDIUM;
}

$poller_seconds_sincerun = 'Never';

if (isset($poller_lastrun)) {
	$poller_seconds_sincerun = round($poller_start - $poller_lastrun, 2);
}

cacti_log("NOTE: Poller Int: '$poller_interval', $task_type Int: '$cron_interval', Time Since Last: '$poller_seconds_sincerun', Max Runtime '" . MAX_POLLER_RUNTIME. "', Poller Runs: '$poller_runs'", true, 'POLLER', $level);

// our cron can run at either 1 or 5 minute intervals
if ($poller_interval <= 60) {
	$min_period = '60';
} else {
	$min_period = '300';
}

// get to see if we are polling faster than reported by the settings, if so, exit
if ((isset($poller_lastrun) && isset($poller_interval) && $poller_lastrun > 0) && (!$force)) {
	// give the user some flexibility to run a little moe often
	if ((($poller_start - $poller_lastrun) * 1.3) < MAX_POLLER_RUNTIME) {
		cacti_log("NOTE: $task_type is configured to run too often!  The Poller Interval is '$poller_interval' seconds, with a minimum $task_type period of '$min_period' seconds, but only " . number_format_i18n($poller_start - $poller_lastrun, 1) . ' seconds have passed since the poller last ran.', true, 'POLLER', $level);

		exit;
	}
}

/* check to see whether we have the poller interval set lower than
 * the poller is actually ran, if so, issue a warning
 */
if ((($poller_start - $poller_lastrun - 5) > MAX_POLLER_RUNTIME) && ($poller_lastrun > 0)) {
	cacti_log("WARNING: $task_type is out of sync with the Poller Interval!  The Poller Interval is '$poller_interval' seconds, with a maximum of a '$min_period' second $task_type, but " . number_format_i18n($poller_start - $poller_lastrun, 1) . ' seconds have passed since the last poll!', true, 'POLLER');
	admin_email(__('Cacti System Warning'), __('WARNING: %s is out of sync with the Poller Interval for Poller[%d]!  The Poller Interval is %d seconds, with a maximum of a %d seconds, but %d seconds have passed since the last poll!', $task_type, $poller_id, $poller_interval, $min_period, number_format_i18n($poller_start - $poller_lastrun, 1)));
}

/* used for current implementation for individual pollers */
set_config_option('poller_lastrun_' . $poller_id, (int)$poller_start);

if ($poller_id == 1) {
	/* used for legacy implementation for the main poller */
	set_config_option('poller_lastrun', (int)$poller_start);
}

/* let PHP only run 1 second longer than the max runtime,
 * plus the poller needs lot's of memory
 */
ini_set('max_execution_time', MAX_POLLER_RUNTIME + 1);
ini_set('memory_limit', '-1');

$poller_runs_completed = 0;
$poller_items_total    = 0;

/**
 * Update poller statistics once per poller run
 */
$script = $server = $snmp = 0;

$totals = db_fetch_assoc_prepared('SELECT action, COUNT(*) AS totals
	FROM poller_item AS pi
	WHERE pi.poller_id = ?
	GROUP BY action',
	array($poller_id));

if (cacti_sizeof($totals)) {
	foreach($totals as $value) {
		switch($value['action']) {
		case '0': // SNMP
			$snmp = $value['totals'];
			break;
		case '1': // Script
			$script = $value['totals'];
			break;
		case '2': // Server
			$server = $value['totals'];
			break;
		}
	}
}

/**
 * Update poller data source statistics in the poller table
 */
db_execute_prepared('INSERT INTO poller (id, snmp, script, server, last_status, status)
	VALUES (?, ?, ?, ?, NOW(), 1)
	ON DUPLICATE KEY UPDATE snmp=VALUES(snmp), script=VALUES(script),
	server=VALUES(server), last_status=VALUES(last_status), status=VALUES(status)',
	array($poller_id, $snmp, $script, $server), true, $poller_db_cnn_id);

/**
 * Freshen the field mappings in cases where they
 * may have gotten out of sync
 */
db_execute('REPLACE INTO poller_data_template_field_mappings
	SELECT dtr.data_template_id, dif.data_name,
	GROUP_CONCAT(DISTINCT dtr.data_source_name ORDER BY dtr.data_source_name) AS data_source_names, NOW()
	FROM graph_templates_item AS gti
	INNER JOIN data_template_rrd AS dtr
	ON gti.task_item_id = dtr.id
	INNER JOIN data_input_fields AS dif
	ON dtr.data_input_field_id = dif.id
	WHERE dtr.local_data_id = 0
	AND gti.local_graph_id = 0
	GROUP BY dtr.data_template_id, dif.data_name');

while ($poller_runs_completed < $poller_runs) {
	// record the start time for this loop
	$loop_start = microtime(true);

	if (db_column_exists('sites', 'disabled')) {
		$sql_where = "AND IFNULL(s.disabled, '') != 'on'";
	} else {
		$sql_where = '';
	}

	if ($poller_id == '1') {
		$polling_hosts = db_fetch_assoc_prepared('SELECT ' . SQL_NO_CACHE . " h.id
			FROM host h
			LEFT JOIN sites s
			ON s.id = h.site_id
			WHERE poller_id = ?
			AND h.deleted = ''
			AND IFNULL(h.disabled,'') != 'on'
			$sql_where
			ORDER BY id",
			array($poller_id));

		$total_polling_hosts = cacti_sizeof($polling_hosts);

		if ($total_polling_hosts) {
			$polling_hosts = array_merge(array(0 => array('id' => '0')), $polling_hosts);
		} else {
			$polling_hosts = array(0 => array('id' => '0'));
		}
	} else {
		$polling_hosts = db_fetch_assoc_prepared('SELECT ' . SQL_NO_CACHE . " h.id
			FROM host h
			LEFT JOIN sites s
			ON s.id = h.site_id
			WHERE poller_id = ?
			AND h.deleted = ''
			AND IFNULL(h.disabled, '') != 'on'
			$sql_where
			ORDER BY id",
			array($poller_id));

		$total_polling_hosts = cacti_sizeof($polling_hosts);
	}

	$hosts_per_process = 0;
	$method            = 'disabled';

	// calculate overhead time
	if ($overhead_time == 0) {
		$overhead_time = $loop_start - $poller_start;
	}

	// initialize counters for script file handling
	$host_count = 1;

	// initialize file creation flags
	$change_proc = false;

	// initialize file and host count pointers
	$started_processes = 0;
	$first_host        = 0;
	$last_host         = 0;
	$rrds_processed    = 0;
	$webroot           = addslashes(($config['cacti_server_os'] == 'win32') ? strtr(strtolower(substr(__DIR__, 0, 1)) . substr(__DIR__, 1),'\\', '/') : __DIR__);

	// update web paths for the poller
	set_config_option('path_webroot', $webroot);

	// obtain some defaults from the database
	$poller_type = read_config_option('poller_type');

	if ($poller_type == '1') {
		$max_threads = '1';
	} elseif (isset($poller['threads'])) {
		$max_threads = $poller['threads'];
	}

	if (intval($max_threads) < 1) {
		$max_threads = 1;
	}

	/* initialize poller_time and poller_output tables,
	 * check poller_output for issues
	 */
	$running_processes = db_fetch_cell_prepared('SELECT ' . SQL_NO_CACHE . ' COUNT(*)
		FROM poller_time
		WHERE poller_id = ?
		AND end_time="0000-00-00 00:00:00"',
		array($poller_id), '', true, $poller_db_cnn_id);

	if ($running_processes) {
		cacti_log("WARNING: There are $running_processes processes detected as overrunning a polling cycle, please investigate", true, 'POLLER');
		admin_email(__('Cacti System Warning'), __('WARNING: There are %d processes detected as overrunning a polling cycle for Poller[%d], please investigate.', $running_processes, $poller_id));
	}

	db_execute_prepared('DELETE FROM poller_time
		WHERE poller_id = ?',
		array($poller_id), true, $poller_db_cnn_id);

	/**
	 * only report issues for the main poller or from bad local
	 * data ids, other pollers may insert somewhat asynchronously
	 */
	$issues       = array();

	$issues_limit = 20;
	$issues_check = ($poller_id == 1 || $config['connection'] == 'online');
	$issues_param = array( $current_time, $poller_id, $poller_id );

	$issues_sql = '
		FROM poller_output AS po
		LEFT JOIN data_local AS dl
		ON po.local_data_id = dl.id
		LEFT JOIN host AS h
		ON dl.host_id = h.id
		WHERE time < FROM_UNIXTIME(? - 600)
		AND (h.poller_id = ? OR h.id IS NULL or ? = 1)';

	if ($issues_check) {
		$issues = db_fetch_assoc_prepared('SELECT ' . SQL_NO_CACHE . '
			local_data_id, rrd_name' . $issues_sql . '
			LIMIT ' . $issues_limit,
			$issues_param);
	}

	if (cacti_sizeof($issues)) {
		$count  = db_fetch_cell_prepared('SELECT ' . SQL_NO_CACHE . '
			COUNT(*)' . $issues_sql,
			$issues_param);

		$issues_list = array();

		foreach ($issues as $issue) {
			$issues_list[]= $issue['local_data_id'];
		}
		$issue_list = 'DS[' . implode(', ', $issues_list) . ']';

		if ($count > $issues_limit) {
			$issue_list .= ", Additional Issues Remain.  Only showing first $issues_limit";
		}

		cacti_log("WARNING: Poller Output Table not Empty.  Issues: $count, $issue_list", true, 'POLLER');

		admin_email(__('Cacti System Warning'), __('WARNING: Poller Output Table not empty for Poller[%d].  Issues: %d, %s.', $poller_id, $count, $issue_list));

		db_execute_prepared('DELETE po ' . $issues_sql, $issues_param);
	}

	/**
	 * adjust for recent memory table problems in MariaDB and memory tables
	 * being pushed into swap
	 */
	if ($poller_id == 1 && read_config_option('poller_refresh_output_table') == 'on' && $total_pollers == 1) {
		db_execute('CREATE TABLE IF NOT EXISTS po LIKE poller_output');
		db_execute('RENAME TABLE poller_output TO poold, po TO poller_output');
		db_execute('DROP TABLE IF EXISTS poold');
		db_execute('ALTER TABLE poller_output ENGINE=MEMORY');

		// catch the unlikely event that the poller_output_boost is missing
		if (!db_table_exists('poller_output_boost')) {
			db_execute('CREATE TABLE poller_output_boost LIKE poller_output');
			db_execute('ALTER TABLE poller_output_boost ENGINE=InnoDB');
		}
	}

	// mainline
	if (read_config_option('poller_enabled') == 'on') {
		// determine the number of hosts to process per file
		$hosts_per_process = ceil(($poller_id == '1' ? $total_polling_hosts - 1 : $total_polling_hosts) / $concurrent_processes);

		$items_launched    = 0;

		// exit poller if spine is selected and file does not exist
		if (($poller_type == '2') && (!file_exists(read_config_option('path_spine')))) {
			cacti_log('ERROR: The spine path: ' . read_config_option('path_spine') . ' is invalid.  Poller can not continue!', true, 'POLLER');

			admin_email(__('Cacti System Warning'), __('ERROR: The spine path: %s is invalid for Poller[%d].  Poller can not continue!', read_config_option('path_spine'), $poller_id));

			exit;
		}

		// determine command name
		if ($poller_type == '2') {
			$command_string = cacti_escapeshellcmd(read_config_option('path_spine'));

			if (read_config_option('path_spine_config') != '' && file_exists(read_config_option('path_spine_config'))) {
				$extra_args     = ' -C ' . cacti_escapeshellarg(read_config_option('path_spine_config'));
			} else {
				$extra_args     = '';
			}

			$method         = 'spine';
			$total_procs    = $concurrent_processes * $max_threads;
			chdir(dirname(read_config_option('path_spine')));
		} elseif ($config['cacti_server_os'] == 'unix') {
			$command_string = cacti_escapeshellcmd(read_config_option('path_php_binary'));
			$extra_args     = '-q ' . cacti_escapeshellarg(CACTI_PATH_BASE . '/cmd.php');
			$method         = 'cmd.php';
			$total_procs    = $concurrent_processes;
		} else {
			$command_string = cacti_escapeshellcmd(read_config_option('path_php_binary'));
			$extra_args     = '-q ' . cacti_escapeshellarg(strtolower(CACTI_PATH_BASE . '/cmd.php'));
			$method         = 'cmd.php';
			$total_procs    = $concurrent_processes;
		}

		if (read_config_option('path_stderrlog') != '' && $config['cacti_server_os'] != 'win32') {
			$extra_parms = '>> ' . read_config_option('path_stderrlog') . ' 2>&1';
		} else {
			$extra_parms = '';
		}

		if ($poller_id > 1) {
			$extra_args .= ' --mode=' . $config['connection'];
		}

		/* Populate each execution file with appropriate information */
		if ($total_polling_hosts) {
			foreach ($polling_hosts as $item) {
				if ($host_count == 1) {
					$first_host = $item['id'];
				}

				if ($process_leveling != 'on') {
					if ($host_count == $hosts_per_process) {
						$last_host    = $item['id'];
						$change_proc  = true;
					}
				} else {
					if (isset($items_perhost[$item['id']])) {
						$items_launched += $items_perhost[$item['id']];
					}

					if (($items_launched >= $items_per_process) ||
						(cacti_sizeof($items_perhost) == $concurrent_processes)) {
						$last_host      = $item['id'];
						/* if this is the dummy entry for externally updated data sources
						 * that are not related to any host (host id = 0), do NOT change_proc */
						$change_proc    = ($item['id'] == 0 ? false : true);
						$items_launched = 0;
					}
				}

				$host_count ++;

				if ($change_proc) {
					exec_background($command_string, "$extra_args --poller=$poller_id --first=$first_host --last=$last_host" . ($mibs ? ' --mibs':''), $extra_parms);
					usleep(100000);

					$host_count   = 1;
					$change_proc  = false;
					$first_host   = 0;
					$last_host    = 0;

					$started_processes++;
				}
			}

			// launch the last process
			if ($host_count > 1) {
				$last_host = $item['id'];

				exec_background($command_string, "$extra_args --poller=$poller_id --first=$first_host --last=$last_host" . ($mibs ? ' --mibs':''), $extra_parms);
				usleep(100000);

				$started_processes++;
			}

			if ($poller_id == 1) {
				// insert the current date/time for graphs
				set_config_option('date', date('Y-m-d H:i:s'));

				// open a pipe to rrdtool for writing
				if (!$boost_enabled) {
					$rrdtool_pipe = rrd_init();
				}
			}

			$rrds_processed              = 0;
			$poller_finishing_dispatched = false;

			while (true) {
				$finished_processes = db_fetch_cell_prepared('SELECT ' . SQL_NO_CACHE . " count(*)
					FROM poller_time
					WHERE poller_id = ?
					AND end_time >'0000-00-00 00:00:00'",
					array($poller_id), '', true, $poller_db_cnn_id);

				if ($finished_processes >= $started_processes) {
					// all scheduled pollers are finished
					if ($poller_finishing_dispatched === false) {
						api_plugin_hook('poller_finishing');
						$poller_finishing_dispatched = true;
					}

					if ($poller_id == 1) {
						$rrds_processed = $rrds_processed + process_poller_output($rrdtool_pipe, true);
					} elseif ($config['connection'] != 'online') {
						/* truncate until formal remote management is supported */
						db_execute('TRUNCATE poller_output');
					}

					log_cacti_stats($loop_start, $method, $concurrent_processes, $max_threads,
						($poller_id == '1' ? $total_polling_hosts - 1 : $total_polling_hosts), $hosts_per_process, $num_polling_items, $rrds_processed);
					poller_run_stats($loop_start);

					break;
				} else {
					if (read_config_option('log_verbosity') >= POLLER_VERBOSITY_MEDIUM || $debug) {
						print 'Waiting on ' . ($started_processes - $finished_processes) . ' of ' . $started_processes . " pollers.\n";
					}

					$mtb = microtime(true);

					if ($poller_id == 1) {
						$rrds_processed = $rrds_processed + process_poller_output($rrdtool_pipe);
					} elseif ($config['connection'] != 'online') {
						/* truncate until formal remote management is supported */
						db_execute('TRUNCATE poller_output');
					}

					// end the process if the runtime exceeds MAX_POLLER_RUNTIME
					if (($poller_start + MAX_POLLER_RUNTIME) < time()) {
						cacti_log('Maximum runtime of ' . MAX_POLLER_RUNTIME . ' seconds exceeded. Exiting.', true, 'POLLER');
						admin_email(__('Cacti System Warning'), __('Maximum runtime of %d seconds exceeded for Poller[%d]. Exiting.', MAX_POLLER_RUNTIME, $poller_id));

						// generate a snmp notification
						snmpagent_poller_exiting();

						api_plugin_hook_function('poller_exiting');
						log_cacti_stats($loop_start, $method, $concurrent_processes, $max_threads,
							($poller_id == '1' ? $total_polling_hosts - 1 : $total_polling_hosts), $hosts_per_process, $num_polling_items, $rrds_processed);
						poller_run_stats($loop_start);

						break;
					}

					if (microtime(true) - $mtb < 1) {
						sleep(1);
					}
				}
			}

			if ($poller_id == 1) {
				rrd_close($rrdtool_pipe);
			}
		}


		// process poller commands
		$commands = db_fetch_cell_prepared('SELECT ' . SQL_NO_CACHE . ' COUNT(*)
			FROM poller_command
			WHERE poller_id = ?',
			array($poller_id), '', true, $poller_db_cnn_id);

		if ($commands > 0) {
			$command_string = cacti_escapeshellcmd(read_config_option('path_php_binary'));
			$extra_args     = '-q ' . cacti_escapeshellarg(CACTI_PATH_BASE . '/poller_commands.php') . ' --poller=' . $poller_id;
			exec_background($command_string, $extra_args);
		} else {
			/* no re-index or Rechache present on this run
			 * in case, we have more PCOMMANDS than recaching, this has to be moved to poller_commands.php
			 * but then we'll have to call it each time to make sure, stats are updated */
			set_config_option('stats_recache_' . $poller_id, 'Poller:' . $poller_id . ' RecacheTime:0.0 DevicesRecached:0');
		}

		if ($method == 'spine') {
			$webroot = read_config_option('path_webroot');

			if (is_dir($webroot)) {
				chdir($webroot);
			}
		}
	} else {
		cacti_log('WARNING: The Cacti Data Collector is currently disabled!', true, 'POLLER');
	}

	$poller_runs_completed++;

	// push records updates to the main poller
	poller_push_data_to_main();

	// record the start time for this loop
	$loop_end  = microtime(true);
	$loop_time = $loop_end - $loop_start;

	if ($loop_time < $poller_interval) {
		// sleep the appropriate amount of time
		if ($poller_runs_completed < $poller_runs) {
			$plugin_start = microtime(true);

			// all plugins moved to core
			if ($poller_id == 1) {
				snmpagent_poller_bottom();
				dsstats_poller_bottom();
				dsdebug_poller_bottom();
				boost_poller_bottom();
			}

			api_plugin_hook('poller_bottom');

			// record the start time for this loop
			$loop_end      = microtime(true);
			$cur_loop_time = $loop_end - $loop_start;

			if ($poller_runs_completed == 1) {
				$sleep_time = $poller_interval - $cur_loop_time - $overhead_time;
			} else {
				$sleep_time = $poller_interval - $cur_loop_time;
			}

			// log some nice debug information
			if ($debug) {
				print 'Loop  Time is: ' . round($loop_time, 2) . "\n";
				print 'Sleep Time is: ' . round($sleep_time, 2) . "\n";
				print 'Total Time is: ' . round($loop_end - $poller_start, 2) . "\n";
			}

			$plugin_end = microtime(true);

			if ($sleep_time > 0) {
				usleep(intval($sleep_time * 1000000));
			}

			api_plugin_hook('poller_top');

			$num_polling_items = db_fetch_cell('SELECT ' . SQL_NO_CACHE . " COUNT(*)
				FROM poller_item AS pi
				INNER JOIN host AS h
				ON h.id = pi.host_id
				LEFT JOIN sites AS s
				ON h.site_id = s.id
				$sql_where");
		}
	} else {
		cacti_log('WARNING: Cacti Polling Cycle Exceeded Poller Interval by ' . round($loop_end - $loop_start - $poller_interval, 2) . ' seconds', true, 'POLLER', $level);
		admin_email(__('Cacti System Warning'), __('WARNING: Cacti Polling Cycle Exceeded Poller Interval by ' . round($loop_end - $loop_start - $poller_interval, 2) . ' seconds', true, 'POLLER', $level));
	}

	if (!$logged) {
		log_cacti_stats($loop_start, $method, $concurrent_processes, $max_threads,
			($poller_id == '1' ? $total_polling_hosts - 1 : $total_polling_hosts), $hosts_per_process, $num_polling_items, $rrds_processed);
		poller_run_stats($loop_start);
	}
}

function poller_heartbeat_check() {
	$poller_interval = read_config_option('poller_interval');

	$heartbeat_pollers = db_fetch_assoc_prepared('SELECT *, UNIX_TIMESTAMP() - UNIX_TIMESTAMP(last_status) AS heartbeat
		FROM poller
		WHERE disabled = ""
		HAVING heartbeat > ? * 2
		OR status = 6',
		array($poller_interval));

	if (cacti_sizeof($heartbeat_pollers)) {
		foreach($heartbeat_pollers as $p) {
			db_execute_prepared('UPDATE poller SET status = 6 WHERE id = ?', array($p['id']));

			if (debounce_run_notification('poller_heartbeat_' . $p['id'], 1800)) {
				$log_message = sprintf('WARNING: Poller[%s] with Name:%s is in Heartbeat Status', $p['id'], $p['name']);
				$email_message = __('WARNING: PollerID:%s with Name:%s is in Heartbeat Status', $p['id'], $p['name']);
				cacti_log($log_message, false, 'POLLER');
				admin_email(__('Poller in Heartbeat Mode'), $email_message);
			}
		}
	}
}

/* start post data processing */
if ($poller_id == 1) {
	multiple_poller_boost_check();
	poller_replicate_check();
	snmpagent_poller_bottom();
	boost_poller_bottom();
	dsstats_poller_bottom();
	dsdebug_poller_bottom();
	reports_poller_bottom();
	spikekill_poller_bottom();
	automation_poller_bottom();
	poller_maintenance();
	rrdcheck_poller_bottom();
	api_plugin_hook('poller_bottom');
	bad_index_check($mibs);
	host_status_cache_check();
	poller_heartbeat_check();
} else {
	// flush the boost table if in recovery mode
	if ($poller_id > 1 && $config['connection'] == 'recovery') {
		cacti_log('NOTE: Remote Data Collection to force processing of boost records.', true, 'POLLER');
		poller_recovery_flush_boost($poller_id);
	}

	automation_poller_bottom();
	poller_maintenance();
	api_plugin_hook('poller_bottom');
}

function host_status_cache_check() {
	$current = db_fetch_cell("SELECT MD5(variable)
		FROM (
			SELECT GROUP_CONCAT(CONCAT(status, '|', hosts)) AS variable
			FROM (
				SELECT status, COUNT(*) AS hosts
				FROM host
				GROUP BY status
			) AS rs
		) AS rs1");

	$last = read_config_option('host_status_cache');

	if ($last != $current) {
		$now = time();
		set_config_option('time_last_change_device', $now);
		set_config_option('time_last_change_site_device', $now);
		set_config_option('host_status_cache', $current);
	}
}

function bad_index_check($mibs) {
	if ($mibs == true) {
		$bad_index_devices = db_fetch_cell('SELECT GROUP_CONCAT(DISTINCT dl.host_id)
			FROM data_local dl
			LEFT JOIN data_template_data dtd
			ON dtd.local_data_id = dl.id
			WHERE dl.snmp_query_id > 0
			AND dl.snmp_index = ""
			AND dtd.active != ""');

		if ($bad_index_devices != '') {
			$bad_indexes = db_fetch_cell('SELECT COUNT(*)
				FROM data_local dl
				LEFT JOIN data_template_data dtd
				ON dtd.local_data_id = dl.id
				WHERE dl.snmp_query_id > 0
				AND dl.snmp_index = ""
				AND dtd.active != ""');

			$devices    = explode(',', $bad_index_devices);
			$device_str = 'Device[' . implode('], Device[', $devices) . ']';

			cacti_log('WARNING: You have ' . cacti_sizeof($devices) . ' Devices with bad SNMP Indexes.  Devices: ' . $device_str . ' totalling ' . $bad_indexes . ' Data Sources.  Please Either Re-Index, Delete or Disable these Data Sources.', false, 'POLLER');
		}
	}
}

function poller_table_maintenance() {
	// catch the unlikely event that the poller_output_boost is missing
	if (!db_table_exists('poller_output_boost')) {
		db_execute('CREATE TABLE poller_output_boost LIKE poller_output');
		db_execute('ALTER TABLE poller_output_boost ENGINE=InnoDB');
	}

	// catch the unlikely event that the poller_output_boost_processes is missing
	if (!db_table_exists('poller_output_boost_processes')) {
		db_execute('CREATE TABLE  `poller_output_boost_processes` (
			`sock_int_value` bigint(20) unsigned NOT NULL auto_increment,
			`status` varchar(255) default NULL,
			PRIMARY KEY (`sock_int_value`))
			ENGINE=MEMORY');
	}

	// catch the unlikely event that the poller_output_realtime is missing
	if (!db_table_exists('poller_output_realtime')) {
		db_execute('CREATE TABLE poller_output_realtime (
			local_data_id int(10) unsigned NOT NULL default "0",
			rrd_name varchar(19) NOT NULL default "",
			`time` timestamp NOT NULL default "0000-00-00 00:00:00",
			output text NOT NULL,
			poller_id varchar(256) NOT NULL default "1",
			PRIMARY KEY (local_data_id, rrd_name, time, poller_id),
			KEY poller_id (poller_id),
			KEY `time` (`time`))
			ENGINE=InnoDB
			ROW_FORMAT=Dynamic');
	}
}

function poller_replicate_check() {
	global $config;
	include_once(CACTI_PATH_LIBRARY . '/poller.php');

	$sync_interval = read_config_option('poller_sync_interval');

	if ($sync_interval == '') {
		$sync_interval = 7200;
	}

	$pollers = db_fetch_assoc("SELECT id
		FROM poller
		WHERE id > 1
		AND dbhost NOT IN ('localhost', '127.0.0.1', '')
		AND disabled = ''
		AND sync_interval != 0
		AND (last_sync = '0000-00-00 00:00:00' OR requires_sync = 'on'
		OR (UNIX_TIMESTAMP()-UNIX_TIMESTAMP(last_sync) >= IFNULL(sync_interval, $sync_interval)))");

	if (cacti_sizeof($pollers)) {
		foreach ($pollers as $poller) {
			$command_string = cacti_escapeshellcmd(read_config_option('path_php_binary'));
			$extra_args     = '-q ' . cacti_escapeshellarg(CACTI_PATH_CLI . '/poller_replicate.php') . ' --poller=' . $poller['id'];
			exec_background($command_string, $extra_args);
		}
	}
}

function poller_enabled_check($poller_id) {
	global $poller_db_cnn_id;

	$poller_disabled = db_fetch_cell_prepared('SELECT disabled
		FROM poller
		WHERE id = ?',
		array($poller_id), '', true, $poller_db_cnn_id);

	$system_enabled = read_config_option('poller_enabled');

	$should_exit = false;

	if ($system_enabled == '') {
		cacti_log('WARNING: System Polling is Disabled!  Therefore, data collection from the poller will be suspended till re-enabled.', true, 'SYSTEM');
		$should_exit = true;
	}

	if ($poller_disabled == 'on') {
		cacti_log('WARNING: Poller ' . $poller_id . ' is Disabled.  Therefore, data collection for this Poller will be suspended till it\'s re-enabled.', true, 'SYSTEM');
		$should_exit = true;
	}

	if ($should_exit) {
		db_execute_prepared('UPDATE poller
			SET last_status=NOW()
			WHERE id = ?',
			array($poller_id), true, $poller_db_cnn_id);

		exit(1);
	}
}

function log_cacti_stats($loop_start, $method, $concurrent_processes, $max_threads, $num_hosts,
	$hosts_per_process, $num_polling_items, $rrds_processed) {
	global $poller_id, $poller_db_cnn_id, $logged;

	// get the poller data
	$poller = db_fetch_row_prepared('SELECT *
		FROM poller
		WHERE id = ?',
		array($poller_id), true, $poller_db_cnn_id);

	// take time and log performance data
	$loop_end = microtime(true);

	$perf_data = array(
		round($loop_end - $loop_start,4),
		$method,
		$concurrent_processes,
		$max_threads,
		$num_hosts,
		$hosts_per_process,
		$num_polling_items,
		$rrds_processed
	);

	$cacti_stats = vsprintf('Time:%01.4f Method:%s Processes:%s Threads:%s Hosts:%s HostsPerProcess:%s DataSources:%s RRDsProcessed:%s', $perf_data);
	cacti_log('STATS: ' . $cacti_stats , true, 'SYSTEM');

	// insert poller stats into the settings table
	if ($poller_id > 1) {
		set_config_option('stats_poller_' . $poller_id, $cacti_stats);
	} else {
		set_config_option('stats_poller', $cacti_stats);
	}

	if (is_array($poller) && array_key_exists('min_time', $poller)) {
		// calculate min/max/average timings
		$total_time  = $loop_end - $loop_start;
		$total_polls = $poller['total_polls'];

		if ($total_time < $poller['min_time'] || $poller['min_time'] == '') {
			$min_time = $total_time;
		} else {
			$min_time = $poller['min_time'];
		}

		if ($total_time > $poller['max_time'] || $poller['max_time'] == '') {
			$max_time = $total_time;
		} else {
			$max_time = $poller['max_time'];
		}

		$avg_time = (($total_polls * $poller['avg_time']) + $total_time) / ($total_polls + 1);

		// insert poller stats into the poller table
		db_execute_prepared('INSERT INTO poller
			(id, total_time, min_time, max_time, avg_time, total_polls, last_update, last_status, status)
			VALUES (?, ?, ?, ?, ?, ?, NOW(), NOW(), 2)
			ON DUPLICATE KEY UPDATE
			total_time = VALUES(total_time),
			min_time = VALUES(min_time),
			max_time = VALUES(max_time),
			avg_time = VALUES(avg_time),
			total_polls = VALUES(total_polls),
			last_update = VALUES(last_update),
			last_status = VALUES(last_status),
			status = VALUES(status)',
			array($poller_id, round($total_time, 4), $min_time, $max_time, $avg_time, $total_polls + 1), true, $poller_db_cnn_id);
	}

	// update snmpcache
	snmpagent_cacti_stats_update($perf_data);

	api_plugin_hook_function('cacti_stats_update', $perf_data);

	$logged = true;
}

function poller_run_stats($loop_start) {
	global $poller_id, $poller_interval, $poller_lastrun;

	if (!db_table_exists('poller_time_stats')) {
		return false;
	}

	$threshold_1h       = read_config_option('poller_warning_1h_ratio');
	$threshold_1h_count = read_config_option('poller_warning_1h_count');
	$threshold_24h      = read_config_option('poller_warning_24h_ratio');

	$loop_end    = microtime(true);
	$total_time  = $loop_end - $loop_start;

	// last day stats
	if (date('j', $poller_lastrun) != date('j')) {
		$min   = db_fetch_cell('SELECT IFNULL(MIN(total_time),0) FROM poller_time_stats');
		$max   = db_fetch_cell('SELECT IFNULL(MAX(total_time),0) FROM poller_time_stats');
		$sum   = db_fetch_cell('SELECT IFNULL(SUM(total_time),0) FROM poller_time_stats');
		$count = db_fetch_cell('SELECT COUNT(total_time) FROM poller_time_stats');

		if ($count > 0) {
			$ratio = round($sum / $count,2);

			cacti_log(__("24 hours avg. poller run time is $ratio seconds, min: $min, max: $max") , true, 'POLLER');

			if ($ratio / $poller_interval > $threshold_24h / 100 && $threshold_24h > 0) {
				cacti_log(__("WARNING: 24 hours poller avg. run time reached more than $threshold_24h% of time limit") , true, 'POLLER');

				admin_email(__('Cacti System Warning'), __('WARNING: 24 hours Poller[%d] avg. run time is %f seconds (more than %d &#37; of time limit)', $poller_id, $ratio,$threshold_24h));
			}
		}
	}

	// last hour stats
	if (date('G', $poller_lastrun) != date('G')) {
		$count = db_fetch_cell_prepared('SELECT count(total_time)
			FROM poller_time_stats
			WHERE time > DATE_SUB(NOW(), INTERVAL 60 minute)
			AND (total_time/?) > (?/100)',
			array($poller_interval, $threshold_1h));

		if ($count > $threshold_1h_count && $threshold_1h_count > 0) {
			cacti_log(__("WARNING: In last hour poller run time $count times (limit $threshold_1h_count) reached more than $threshold_1h% of time limit") , true, 'POLLER');

			admin_email(__('Cacti System Warning'), __('WARNING: In last hour Poller[%d] run time %d times reached more than %d &#37; of time limit', $poller_id, $threshold_1h_count, $threshold_1h));
		}
	}

	// poller time statistics for last day
	db_execute_prepared('INSERT INTO poller_time_stats (poller_id,total_time,time)
		VALUES (?,?,now())',
		array($poller_id, round($total_time, 4)));

	// delete old stats
	db_execute('DELETE FROM poller_time_stats WHERE `time` <  DATE_SUB(NOW(), INTERVAL 24 HOUR)');
}

function multiple_poller_boost_check() {
	$pollers = db_fetch_cell('SELECT COUNT(*)
		FROM poller
		WHERE disabled = ""
		AND id > 1');

	if ($pollers > 0 && read_config_option('boost_rrd_update_enable') == '') {
		cacti_log('NOTE: A second Cacti data collector has been added.  Therefore, enabling boost automatically!', false, 'POLLER');

		admin_email(__('Cacti System Notification'), __('NOTE: A second Cacti data collector has been added.  Therefore, enabling boost automatically!'));

		set_config_option('boost_rrd_update_enable', 'on');
		set_config_option('boost_rrd_update_system_enable', 'on');
	}
}

/**
 * function for bulk spikekill that only runs on the main cacti server
 */
function spikekill_poller_bottom() {
	global $config;

	include_once(CACTI_PATH_LIBRARY . '/poller.php');

	$command_string = cacti_escapeshellcmd(read_config_option('path_php_binary'));
	$extra_args     = '-q ' . cacti_escapeshellarg(CACTI_PATH_BASE . '/poller_spikekill.php');
	exec_background($command_string, $extra_args);
}

/*  display_version - displays version information */
function display_version() {
	$version = get_cacti_cli_version();
	print "Cacti Main Poller, Version $version, " . COPYRIGHT_YEARS . "\n";
}

function display_help() {
	display_version();

	print "\nusage: poller.php [--poller=ID] [--force] [--debug]\n\n";
	print "Cacti's main poller.  This poller is the launcher of cmd.php, spine, and all other\n";
	print "background processes.  It is the heart of Cacti's data collection engine.\n\n";
	print "Optional:\n";
	print "    --poller=ID    Run as the poller indicated and not the default poller.\n";
	print "    --force        Override poller overrun detection and force a poller run.\n";
	print "    --debug|-d     Output debug information.  Similar to cacti's DEBUG logging level.\n\n";
}