830 lines
22 KiB
C
830 lines
22 KiB
C
/*
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* This file is distributed as part of the MariaDB Corporation MaxScale. It is free
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* software: you can redistribute it and/or modify it under the terms of the
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* GNU General Public License as published by the Free Software Foundation,
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* version 2.
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*
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* This program is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
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* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
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* details.
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*
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* You should have received a copy of the GNU General Public License along with
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* this program; if not, write to the Free Software Foundation, Inc., 51
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* Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Copyright MariaDB Corporation Ab 2013-2014
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*/
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/**
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* @file galera_mon.c - A MySQL Galera cluster monitor
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*
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* @verbatim
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* Revision History
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*
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* Date Who Description
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* 22/07/13 Mark Riddoch Initial implementation
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* 21/05/14 Massimiliano Pinto Monitor sets a master server
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* that has the lowest value of wsrep_local_index
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* 23/05/14 Massimiliano Pinto Added 1 configuration option (setInterval).
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* Interval is printed in diagnostics.
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* 03/06/14 Mark Riddoch Add support for maintenance mode
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* 24/06/14 Massimiliano Pinto Added depth level 0 for each node
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* 30/10/14 Massimiliano Pinto Added disableMasterFailback feature
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* 10/11/14 Massimiliano Pinto Added setNetworkTimeout for connect,read,write
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*
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* @endverbatim
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*/
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <monitor.h>
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#include <mysqlmon.h>
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#include <thread.h>
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#include <mysql.h>
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#include <mysqld_error.h>
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#include <skygw_utils.h>
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#include <log_manager.h>
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#include <secrets.h>
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#include <dcb.h>
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#include <modinfo.h>
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/** Defined in log_manager.cc */
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extern int lm_enabled_logfiles_bitmask;
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extern size_t log_ses_count[];
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extern __thread log_info_t tls_log_info;
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static void monitorMain(void *);
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static char *version_str = "V1.4.0";
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MODULE_INFO info = {
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MODULE_API_MONITOR,
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MODULE_GA,
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MONITOR_VERSION,
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"A Galera cluster monitor"
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};
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static void *startMonitor(void *);
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static void stopMonitor(void *);
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static void registerServer(void *, SERVER *);
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static void unregisterServer(void *, SERVER *);
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static void defaultUsers(void *, char *, char *);
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static void diagnostics(DCB *, void *);
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static void setInterval(void *, size_t);
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static MONITOR_SERVERS *get_candidate_master(MONITOR_SERVERS *);
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static MONITOR_SERVERS *set_cluster_master(MONITOR_SERVERS *, MONITOR_SERVERS *, int);
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static void disableMasterFailback(void *, int);
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static void setNetworkTimeout(void *arg, int type, int value);
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static bool mon_status_changed(MONITOR_SERVERS* mon_srv);
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static bool mon_print_fail_status(MONITOR_SERVERS* mon_srv);
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static MONITOR_OBJECT MyObject = {
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startMonitor,
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stopMonitor,
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registerServer,
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unregisterServer,
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defaultUsers,
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diagnostics,
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setInterval,
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setNetworkTimeout,
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NULL,
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NULL,
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NULL,
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disableMasterFailback
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};
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/**
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* Implementation of the mandatory version entry point
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*
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* @return version string of the module
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*/
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char *
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version()
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{
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return version_str;
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}
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/**
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* The module initialisation routine, called when the module
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* is first loaded.
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*/
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void
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ModuleInit()
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{
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LOGIF(LM, (skygw_log_write(
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LOGFILE_MESSAGE,
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"Initialise the MySQL Galera Monitor module %s.\n",
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version_str)));
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}
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/**
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* The module entry point routine. It is this routine that
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* must populate the structure that is referred to as the
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* "module object", this is a structure with the set of
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* external entry points for this module.
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*
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* @return The module object
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*/
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MONITOR_OBJECT *
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GetModuleObject()
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{
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return &MyObject;
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}
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/**
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* Start the instance of the monitor, returning a handle on the monitor.
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*
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* This function creates a thread to execute the actual monitoring.
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*
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* @return A handle to use when interacting with the monitor
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*/
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static void *
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startMonitor(void *arg)
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{
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MYSQL_MONITOR *handle;
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if (arg != NULL)
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{
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handle = (MYSQL_MONITOR *)arg;
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handle->shutdown = 0;
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}
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else
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{
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if ((handle = (MYSQL_MONITOR *)malloc(sizeof(MYSQL_MONITOR))) == NULL)
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return NULL;
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handle->databases = NULL;
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handle->shutdown = 0;
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handle->defaultUser = NULL;
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handle->defaultPasswd = NULL;
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handle->id = MONITOR_DEFAULT_ID;
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handle->interval = MONITOR_INTERVAL;
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handle->disableMasterFailback = 0;
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handle->master = NULL;
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handle->connect_timeout=DEFAULT_CONNECT_TIMEOUT;
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handle->read_timeout=DEFAULT_READ_TIMEOUT;
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handle->write_timeout=DEFAULT_WRITE_TIMEOUT;
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spinlock_init(&handle->lock);
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}
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handle->tid = (THREAD)thread_start(monitorMain, handle);
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return handle;
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}
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/**
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* Stop a running monitor
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*
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* @param arg Handle on thr running monior
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*/
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static void
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stopMonitor(void *arg)
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{
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MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
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handle->shutdown = 1;
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thread_wait((void *)handle->tid);
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}
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/**
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* Register a server that must be added to the monitored servers for
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* a monitoring module.
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*
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* @param arg A handle on the running monitor module
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* @param server The server to add
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*/
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static void
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registerServer(void *arg, SERVER *server)
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{
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MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
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MONITOR_SERVERS *ptr, *db;
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if ((db = (MONITOR_SERVERS *)malloc(sizeof(MONITOR_SERVERS))) == NULL)
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return;
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db->server = server;
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db->con = NULL;
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db->next = NULL;
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spinlock_acquire(&handle->lock);
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if (handle->databases == NULL)
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handle->databases = db;
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else
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{
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ptr = handle->databases;
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while (ptr->next != NULL)
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ptr = ptr->next;
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ptr->next = db;
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}
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spinlock_release(&handle->lock);
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}
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/**
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* Remove a server from those being monitored by a monitoring module
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*
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* @param arg A handle on the running monitor module
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* @param server The server to remove
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*/
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static void
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unregisterServer(void *arg, SERVER *server)
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{
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MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
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MONITOR_SERVERS *ptr, *lptr;
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spinlock_acquire(&handle->lock);
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if (handle->databases == NULL)
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{
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spinlock_release(&handle->lock);
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return;
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}
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if (handle->databases->server == server)
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{
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ptr = handle->databases;
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handle->databases = handle->databases->next;
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free(ptr);
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}
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else
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{
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ptr = handle->databases;
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while (ptr->next != NULL && ptr->next->server != server)
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ptr = ptr->next;
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if (ptr->next)
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{
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lptr = ptr->next;
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ptr->next = ptr->next->next;
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free(lptr);
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}
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}
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spinlock_release(&handle->lock);
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}
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/**
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* Diagnostic interface
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*
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* @param dcb DCB to send output
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* @param arg The monitor handle
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*/
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static void
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diagnostics(DCB *dcb, void *arg)
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{
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MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
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MONITOR_SERVERS *db;
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char *sep;
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switch (handle->status)
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{
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case MONITOR_RUNNING:
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dcb_printf(dcb, "\tMonitor running\n");
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break;
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case MONITOR_STOPPING:
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dcb_printf(dcb, "\tMonitor stopping\n");
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break;
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case MONITOR_STOPPED:
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dcb_printf(dcb, "\tMonitor stopped\n");
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break;
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}
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dcb_printf(dcb,"\tSampling interval:\t%lu milliseconds\n", handle->interval);
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dcb_printf(dcb,"\tMaster Failback:\t%s\n", (handle->disableMasterFailback == 1) ? "off" : "on");
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dcb_printf(dcb,"\tConnect Timeout:\t%i seconds\n", handle->connect_timeout);
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dcb_printf(dcb,"\tRead Timeout:\t\t%i seconds\n", handle->read_timeout);
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dcb_printf(dcb,"\tWrite Timeout:\t\t%i seconds\n", handle->write_timeout);
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dcb_printf(dcb, "\tMonitored servers: ");
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db = handle->databases;
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sep = "";
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while (db)
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{
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dcb_printf(dcb, "%s%s:%d", sep, db->server->name, db->server->port);
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sep = ", ";
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db = db->next;
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}
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dcb_printf(dcb, "\n");
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}
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/**
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* Set the default username and password to use to monitor if the server does not
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* override this.
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*
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* @param arg The handle allocated by startMonitor
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* @param uname The default user name
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* @param passwd The default password
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*/
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static void
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defaultUsers(void *arg, char *uname, char *passwd)
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{
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MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
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if (handle->defaultUser)
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free(handle->defaultUser);
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if (handle->defaultPasswd)
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free(handle->defaultPasswd);
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handle->defaultUser = strdup(uname);
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handle->defaultPasswd = strdup(passwd);
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}
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/**
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* Monitor an individual server
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*
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* @param handle The MySQL Monitor object
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* @param database The database to probe
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*/
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static void
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monitorDatabase(MYSQL_MONITOR *handle, MONITOR_SERVERS *database)
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{
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MYSQL_ROW row;
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MYSQL_RES *result;
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int num_fields;
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int isjoined = 0;
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char *uname = handle->defaultUser;
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char *passwd = handle->defaultPasswd;
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unsigned long int server_version = 0;
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char *server_string;
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if (database->server->monuser != NULL)
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{
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uname = database->server->monuser;
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passwd = database->server->monpw;
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}
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if (uname == NULL)
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return;
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/* Don't even probe server flagged as in maintenance */
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if (SERVER_IN_MAINT(database->server))
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return;
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/** Store previous status */
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database->mon_prev_status = database->server->status;
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if (database->con == NULL || mysql_ping(database->con) != 0)
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{
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char *dpwd = decryptPassword(passwd);
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int rc;
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int connect_timeout = handle->connect_timeout;
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int read_timeout = handle->read_timeout;
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int write_timeout = handle->write_timeout;
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database->con = mysql_init(NULL);
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rc = mysql_options(database->con, MYSQL_OPT_CONNECT_TIMEOUT, (void *)&connect_timeout);
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rc = mysql_options(database->con, MYSQL_OPT_READ_TIMEOUT, (void *)&read_timeout);
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rc = mysql_options(database->con, MYSQL_OPT_WRITE_TIMEOUT, (void *)&write_timeout);
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if (mysql_real_connect(database->con, database->server->name,
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uname, dpwd, NULL, database->server->port, NULL, 0) == NULL)
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{
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free(dpwd);
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server_clear_status(database->server, SERVER_RUNNING);
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/* Also clear Joined, M/S and Stickiness bits */
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server_clear_status(database->server, SERVER_JOINED);
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server_clear_status(database->server, SERVER_SLAVE);
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server_clear_status(database->server, SERVER_MASTER);
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server_clear_status(database->server, SERVER_MASTER_STICKINESS);
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if (mysql_errno(database->con) == ER_ACCESS_DENIED_ERROR)
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{
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server_set_status(database->server, SERVER_AUTH_ERROR);
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}
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database->server->node_id = -1;
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if (mon_status_changed(database) && mon_print_fail_status(database))
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{
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LOGIF(LE, (skygw_log_write_flush(
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LOGFILE_ERROR,
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"Error : Monitor was unable to connect to "
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"server %s:%d : \"%s\"",
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database->server->name,
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database->server->port,
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mysql_error(database->con))));
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}
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return;
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}
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else
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{
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server_clear_status(database->server, SERVER_AUTH_ERROR);
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}
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free(dpwd);
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}
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/* If we get this far then we have a working connection */
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server_set_status(database->server, SERVER_RUNNING);
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/* get server version from current server */
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server_version = mysql_get_server_version(database->con);
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/* get server version string */
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server_string = (char *)mysql_get_server_info(database->con);
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if (server_string) {
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database->server->server_string = realloc(database->server->server_string, strlen(server_string)+1);
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if (database->server->server_string)
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strcpy(database->server->server_string, server_string);
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}
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/* Check if the the Galera FSM shows this node is joined to the cluster */
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if (mysql_query(database->con, "SHOW STATUS LIKE 'wsrep_local_state_comment'") == 0
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&& (result = mysql_store_result(database->con)) != NULL)
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{
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num_fields = mysql_num_fields(result);
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while ((row = mysql_fetch_row(result)))
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{
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if (strncasecmp(row[1], "SYNCED", 3) == 0)
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isjoined = 1;
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}
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mysql_free_result(result);
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}
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/* Check the the Galera node index in the cluster */
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if (mysql_query(database->con, "SHOW STATUS LIKE 'wsrep_local_index'") == 0
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&& (result = mysql_store_result(database->con)) != NULL)
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{
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long local_index = -1;
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num_fields = mysql_num_fields(result);
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while ((row = mysql_fetch_row(result)))
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{
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local_index = strtol(row[1], NULL, 10);
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if ((errno == ERANGE && (local_index == LONG_MAX
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|| local_index == LONG_MIN)) || (errno != 0 && local_index == 0))
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{
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local_index = -1;
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}
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database->server->node_id = local_index;
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}
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mysql_free_result(result);
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}
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if (isjoined)
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server_set_status(database->server, SERVER_JOINED);
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else
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server_clear_status(database->server, SERVER_JOINED);
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}
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/**
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* The entry point for the monitoring module thread
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*
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* @param arg The handle of the monitor
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*/
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static void
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monitorMain(void *arg)
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{
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MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
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MONITOR_SERVERS *ptr;
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size_t nrounds = 0;
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MONITOR_SERVERS *candidate_master = NULL;
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int master_stickiness = handle->disableMasterFailback;
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int is_cluster=0;
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int log_no_members = 1;
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if (mysql_thread_init())
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{
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LOGIF(LE, (skygw_log_write_flush(
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LOGFILE_ERROR,
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"Fatal : mysql_thread_init failed in monitor "
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"module. Exiting.\n")));
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return;
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}
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handle->status = MONITOR_RUNNING;
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while (1)
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{
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if (handle->shutdown)
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{
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handle->status = MONITOR_STOPPING;
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mysql_thread_end();
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handle->status = MONITOR_STOPPED;
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return;
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}
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/** Wait base interval */
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thread_millisleep(MON_BASE_INTERVAL_MS);
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/**
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* Calculate how far away the monitor interval is from its full
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* cycle and if monitor interval time further than the base
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* interval, then skip monitoring checks. Excluding the first
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* round.
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*/
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if (nrounds != 0 && ((nrounds*MON_BASE_INTERVAL_MS)%handle->interval) >= MON_BASE_INTERVAL_MS)
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{
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nrounds += 1;
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continue;
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}
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nrounds += 1;
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/* reset cluster members counter */
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is_cluster=0;
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ptr = handle->databases;
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while (ptr)
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{
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monitorDatabase(handle, ptr);
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/* clear bits for non member nodes */
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if ( ! SERVER_IN_MAINT(ptr->server) && (ptr->server->node_id < 0 || ! SERVER_IS_JOINED(ptr->server))) {
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ptr->server->depth = -1;
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/* clear M/S status */
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server_clear_status(ptr->server, SERVER_SLAVE);
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server_clear_status(ptr->server, SERVER_MASTER);
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/* clear master sticky status */
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server_clear_status(ptr->server, SERVER_MASTER_STICKINESS);
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}
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/* Log server status change */
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if (mon_status_changed(ptr))
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{
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LOGIF(LD, (skygw_log_write_flush(
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LOGFILE_DEBUG,
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|
"Backend server %s:%d state : %s",
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ptr->server->name,
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ptr->server->port,
|
|
STRSRVSTATUS(ptr->server))));
|
|
}
|
|
|
|
if (SERVER_IS_DOWN(ptr->server))
|
|
{
|
|
/** Increase this server'e error count */
|
|
ptr->mon_err_count += 1;
|
|
}
|
|
else
|
|
{
|
|
/** Reset this server's error count */
|
|
ptr->mon_err_count = 0;
|
|
}
|
|
|
|
ptr = ptr->next;
|
|
}
|
|
|
|
/*
|
|
* Let's select a master server:
|
|
* it could be the candidate master following MIN(node_id) rule or
|
|
* the server that was master in the previous monitor polling cycle
|
|
* Decision depends on master_stickiness value set in configuration
|
|
*/
|
|
|
|
/* get the candidate master, followinf MIN(node_id) rule */
|
|
candidate_master = get_candidate_master(handle->databases);
|
|
|
|
/* Select the master, based on master_stickiness */
|
|
handle->master = set_cluster_master(handle->master, candidate_master, master_stickiness);
|
|
|
|
ptr = handle->databases;
|
|
|
|
while (ptr && handle->master) {
|
|
if (!SERVER_IS_JOINED(ptr->server) || SERVER_IN_MAINT(ptr->server)) {
|
|
ptr = ptr->next;
|
|
continue;
|
|
}
|
|
|
|
if (ptr != handle->master) {
|
|
/* set the Slave role */
|
|
server_set_status(ptr->server, SERVER_SLAVE);
|
|
server_clear_status(ptr->server, SERVER_MASTER);
|
|
|
|
/* clear master stickyness */
|
|
server_clear_status(ptr->server, SERVER_MASTER_STICKINESS);
|
|
} else {
|
|
/* set the Master role */
|
|
server_set_status(handle->master->server, SERVER_MASTER);
|
|
server_clear_status(handle->master->server, SERVER_SLAVE);
|
|
|
|
if (candidate_master && handle->master->server->node_id != candidate_master->server->node_id) {
|
|
/* set master stickyness */
|
|
server_set_status(handle->master->server, SERVER_MASTER_STICKINESS);
|
|
} else {
|
|
/* clear master stickyness */
|
|
server_clear_status(ptr->server, SERVER_MASTER_STICKINESS);
|
|
}
|
|
}
|
|
|
|
is_cluster++;
|
|
|
|
ptr = ptr->next;
|
|
}
|
|
|
|
if (is_cluster == 0 && log_no_members) {
|
|
LOGIF(LE, (skygw_log_write_flush(
|
|
LOGFILE_ERROR,
|
|
"Error: there are no cluster members")));
|
|
log_no_members = 0;
|
|
} else {
|
|
if (is_cluster > 0 && log_no_members == 0) {
|
|
LOGIF(LE, (skygw_log_write_flush(
|
|
LOGFILE_ERROR,
|
|
"Info: found cluster members")));
|
|
log_no_members = 1;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Set the monitor sampling interval.
|
|
*
|
|
* @param arg The handle allocated by startMonitor
|
|
* @param interval The interval to set in monitor struct, in milliseconds
|
|
*/
|
|
static void
|
|
setInterval(void *arg, size_t interval)
|
|
{
|
|
MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
|
|
memcpy(&handle->interval, &interval, sizeof(unsigned long));
|
|
}
|
|
|
|
/**
|
|
* get candidate master from all nodes
|
|
*
|
|
* The current available rule: get the server with MIN(node_id)
|
|
* node_id comes from 'wsrep_local_index' variable
|
|
*
|
|
* @param servers The monitored servers list
|
|
* @return The candidate master on success, NULL on failure
|
|
*/
|
|
static MONITOR_SERVERS *get_candidate_master(MONITOR_SERVERS *servers) {
|
|
MONITOR_SERVERS *ptr = servers;
|
|
MONITOR_SERVERS *candidate_master = NULL;
|
|
long min_id = -1;
|
|
|
|
/* set min_id to the lowest value of ptr->server->node_id */
|
|
while(ptr) {
|
|
if ((! SERVER_IN_MAINT(ptr->server)) && ptr->server->node_id >= 0 && SERVER_IS_JOINED(ptr->server)) {
|
|
ptr->server->depth = 0;
|
|
if ((ptr->server->node_id < min_id) && min_id >= 0) {
|
|
min_id = ptr->server->node_id;
|
|
candidate_master = ptr;
|
|
} else {
|
|
if (min_id < 0) {
|
|
min_id = ptr->server->node_id;
|
|
candidate_master = ptr;
|
|
}
|
|
}
|
|
}
|
|
|
|
ptr = ptr->next;
|
|
}
|
|
|
|
return candidate_master;
|
|
}
|
|
|
|
/**
|
|
* set the master server in the cluster
|
|
*
|
|
* master could be the last one from previous monitor cycle Iis running) or
|
|
* the candidate master.
|
|
* The selection is based on the configuration option mapped to master_stickiness
|
|
* The candidate master may change over time due to
|
|
* 'wsrep_local_index' value change in the Galera Cluster
|
|
* Enabling master_stickiness will avoid master change unless a failure is spotted
|
|
*
|
|
* @param current_master Previous master server
|
|
* @param candidate_master The candidate master server accordingly to the selection rule
|
|
* @return The master node pointer (could be NULL)
|
|
*/
|
|
static MONITOR_SERVERS *set_cluster_master(MONITOR_SERVERS *current_master, MONITOR_SERVERS *candidate_master, int master_stickiness) {
|
|
/*
|
|
* if current master is not set or master_stickiness is not enable
|
|
* just return candidate_master.
|
|
*/
|
|
if (current_master == NULL || master_stickiness == 0) {
|
|
return candidate_master;
|
|
} else {
|
|
/*
|
|
* if current_master is still a cluster member use it
|
|
*
|
|
*/
|
|
if (SERVER_IS_JOINED(current_master->server) && (! SERVER_IN_MAINT(current_master->server))) {
|
|
return current_master;
|
|
} else
|
|
return candidate_master;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Disable/Enable the Master failback in a Galera Cluster.
|
|
*
|
|
* A restarted / rejoined node may get back the previous 'wsrep_local_index'
|
|
* from Cluster: if the value is the lowest in the cluster it will be selected as Master
|
|
* This will cause a Master change even if there is no failure.
|
|
* The option if set to 1 will avoid this situation, keeping the current Master (if running) available
|
|
*
|
|
* @param arg The handle allocated by startMonitor
|
|
* @param disable To disable it use 1, 0 keeps failback
|
|
*/
|
|
static void
|
|
disableMasterFailback(void *arg, int disable)
|
|
{
|
|
MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
|
|
memcpy(&handle->disableMasterFailback, &disable, sizeof(int));
|
|
}
|
|
|
|
/**
|
|
* Set the timeouts to use in the monitor.
|
|
*
|
|
* @param arg The handle allocated by startMonitor
|
|
* @param type The connect timeout type
|
|
* @param value The timeout value to set
|
|
*/
|
|
static void
|
|
setNetworkTimeout(void *arg, int type, int value)
|
|
{
|
|
MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
|
|
int max_timeout = (int)(handle->interval/1000);
|
|
int new_timeout = max_timeout -1;
|
|
|
|
if (new_timeout <= 0)
|
|
new_timeout = DEFAULT_CONNECT_TIMEOUT;
|
|
|
|
switch(type) {
|
|
case MONITOR_CONNECT_TIMEOUT:
|
|
if (value < max_timeout) {
|
|
memcpy(&handle->connect_timeout, &value, sizeof(int));
|
|
} else {
|
|
memcpy(&handle->connect_timeout, &new_timeout, sizeof(int));
|
|
LOGIF(LE, (skygw_log_write_flush(
|
|
LOGFILE_ERROR,
|
|
"warning : Monitor Connect Timeout %i is greater than monitor interval ~%i seconds"
|
|
", lowering to %i seconds", value, max_timeout, new_timeout)));
|
|
}
|
|
break;
|
|
|
|
case MONITOR_READ_TIMEOUT:
|
|
if (value < max_timeout) {
|
|
memcpy(&handle->read_timeout, &value, sizeof(int));
|
|
} else {
|
|
memcpy(&handle->read_timeout, &new_timeout, sizeof(int));
|
|
LOGIF(LE, (skygw_log_write_flush(
|
|
LOGFILE_ERROR,
|
|
"warning : Monitor Read Timeout %i is greater than monitor interval ~%i seconds"
|
|
", lowering to %i seconds", value, max_timeout, new_timeout)));
|
|
}
|
|
break;
|
|
|
|
case MONITOR_WRITE_TIMEOUT:
|
|
if (value < max_timeout) {
|
|
memcpy(&handle->write_timeout, &value, sizeof(int));
|
|
} else {
|
|
memcpy(&handle->write_timeout, &new_timeout, sizeof(int));
|
|
LOGIF(LE, (skygw_log_write_flush(
|
|
LOGFILE_ERROR,
|
|
"warning : Monitor Write Timeout %i is greater than monitor interval ~%i seconds"
|
|
", lowering to %i seconds", value, max_timeout, new_timeout)));
|
|
}
|
|
break;
|
|
default:
|
|
LOGIF(LE, (skygw_log_write_flush(
|
|
LOGFILE_ERROR,
|
|
"Error : Monitor setNetworkTimeout received an unsupported action type %i", type)));
|
|
break;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Check if current monitored server status has changed
|
|
*
|
|
* @param mon_srv The monitored server
|
|
* @return true if status has changed or false
|
|
*/
|
|
static bool mon_status_changed(
|
|
MONITOR_SERVERS* mon_srv)
|
|
{
|
|
bool succp;
|
|
|
|
if (mon_srv->mon_prev_status != mon_srv->server->status)
|
|
{
|
|
succp = true;
|
|
}
|
|
else
|
|
{
|
|
succp = false;
|
|
}
|
|
return succp;
|
|
}
|
|
|
|
/**
|
|
* Check if current monitored server has a loggable failure status
|
|
*
|
|
* @param mon_srv The monitored server
|
|
* @return true if failed status can be logged or false
|
|
*/
|
|
static bool mon_print_fail_status(
|
|
MONITOR_SERVERS* mon_srv)
|
|
{
|
|
bool succp;
|
|
int errcount = mon_srv->mon_err_count;
|
|
uint8_t modval;
|
|
|
|
modval = 1<<(MIN(errcount/10, 7));
|
|
|
|
if (SERVER_IS_DOWN(mon_srv->server) && errcount == 0)
|
|
{
|
|
succp = true;
|
|
}
|
|
else
|
|
{
|
|
succp = false;
|
|
}
|
|
return succp;
|
|
}
|