808 lines
23 KiB
C
808 lines
23 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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* 20/04/15 Guillaume Lefranc Added availableWhenDonor feature
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* 22/04/15 Martin Brampton Addition of disableMasterRoleSetting
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* 08/05/15 Markus Makela Addition of launchable scripts
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*
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* @endverbatim
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*/
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#include <galeramon.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 = "V2.0.0";
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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 *,void*);
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static void stopMonitor(void *);
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static void diagnostics(DCB *, void *);
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static MONITOR_SERVERS *get_candidate_master(MONITOR*);
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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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bool isGaleraEvent(monitor_event_t event);
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static MONITOR_OBJECT MyObject = {
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startMonitor,
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stopMonitor,
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diagnostics
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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,void* opt)
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{
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MONITOR* mon = arg;
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GALERA_MONITOR *handle = mon->handle;
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CONFIG_PARAMETER* params = (CONFIG_PARAMETER*)opt;
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bool have_events = false,script_error = false;
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if (handle != NULL)
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{
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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 = (GALERA_MONITOR *)malloc(sizeof(GALERA_MONITOR))) == NULL)
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return NULL;
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handle->shutdown = 0;
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handle->id = MONITOR_DEFAULT_ID;
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handle->disableMasterFailback = 0;
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handle->availableWhenDonor = 0;
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handle->disableMasterRoleSetting = 0;
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handle->master = NULL;
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handle->script = NULL;
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handle->use_priority = false;
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memset(handle->events,false,sizeof(handle->events));
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spinlock_init(&handle->lock);
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}
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while(params)
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{
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if(!strcmp(params->name,"disable_master_failback"))
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handle->disableMasterFailback = config_truth_value(params->value);
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else if(!strcmp(params->name,"available_when_donor"))
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handle->availableWhenDonor = config_truth_value(params->value);
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else if(!strcmp(params->name,"disable_master_role_setting"))
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handle->disableMasterRoleSetting = config_truth_value(params->value);
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else if(!strcmp(params->name,"use_priority"))
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handle->use_priority = config_truth_value(params->value);
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else if(!strcmp(params->name,"script"))
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{
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if(handle->script)
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{
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free(handle->script);
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handle->script = NULL;
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}
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if(access(params->value,X_OK) == 0)
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{
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handle->script = strdup(params->value);
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}
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else
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{
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script_error = true;
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if(access(params->value,F_OK) == 0)
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{
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skygw_log_write(LE,
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"Error: The file cannot be executed: %s",
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params->value);
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}
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else
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{
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skygw_log_write(LE,
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"Error: The file cannot be found: %s",
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params->value);
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}
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}
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}
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else if(!strcmp(params->name,"events"))
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{
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if(mon_parse_event_string((bool*)&handle->events,sizeof(handle->events),params->value) != 0)
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script_error = true;
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else
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have_events = true;
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}
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params = params->next;
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}
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if(script_error)
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{
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skygw_log_write(LE,"Error: Errors were found in the script configuration parameters "
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"for the monitor '%s'. The script will not be used.",mon->name);
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free(handle->script);
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handle->script = NULL;
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}
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/** If no specific events are given, enable them all */
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if(!have_events)
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{
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memset(handle->events,true,sizeof(handle->events));
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}
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handle->tid = (THREAD)thread_start(monitorMain, mon);
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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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MONITOR* mon = (MONITOR*)arg;
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GALERA_MONITOR *handle = (GALERA_MONITOR *)mon->handle;
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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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* 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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MONITOR* mon = (MONITOR*)arg;
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GALERA_MONITOR *handle = (GALERA_MONITOR *)mon->handle;
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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", mon->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,"\tAvailable when Donor:\t%s\n", (handle->availableWhenDonor == 1) ? "on" : "off");
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dcb_printf(dcb,"\tMaster Role Setting Disabled:\t%s\n", (handle->disableMasterRoleSetting == 1) ? "on" : "off");
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dcb_printf(dcb,"\tConnect Timeout:\t%i seconds\n", mon->connect_timeout);
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dcb_printf(dcb,"\tRead Timeout:\t\t%i seconds\n", mon->read_timeout);
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dcb_printf(dcb,"\tWrite Timeout:\t\t%i seconds\n", mon->write_timeout);
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dcb_printf(dcb, "\tMonitored servers: ");
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db = mon->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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* 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(MONITOR *mon, MONITOR_SERVERS *database)
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{
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GALERA_MONITOR* handle = (GALERA_MONITOR*)mon->handle;
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MYSQL_ROW row;
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MYSQL_RES *result,*result2;
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int isjoined = 0;
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char *uname = mon->user;
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char *passwd = mon->password;
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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 connect_timeout = mon->connect_timeout;
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int read_timeout = mon->read_timeout;
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int write_timeout = mon->write_timeout;
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if(database->con)
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mysql_close(database->con);
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database->con = mysql_init(NULL);
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mysql_options(database->con, MYSQL_OPT_CONNECT_TIMEOUT, (void *)&connect_timeout);
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mysql_options(database->con, MYSQL_OPT_READ_TIMEOUT, (void *)&read_timeout);
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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 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'") == 0
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&& (result = mysql_store_result(database->con)) != NULL)
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{
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if(mysql_field_count(database->con) < 2)
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{
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mysql_free_result(result);
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skygw_log_write(LE,"Error: Unexpected result for \"SHOW STATUS LIKE 'wsrep_local_state'\". Expected 2 columns."
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" MySQL Version: %s",version_str);
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return;
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}
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while ((row = mysql_fetch_row(result)))
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{
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if (strcmp(row[1], "4") == 0)
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isjoined = 1;
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/* Check if the node is a donor and is using xtrabackup, in this case it can stay alive */
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else if (strcmp(row[1], "2") == 0 && handle->availableWhenDonor == 1) {
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if (mysql_query(database->con, "SHOW VARIABLES LIKE 'wsrep_sst_method'") == 0
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&& (result2 = mysql_store_result(database->con)) != NULL)
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{
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if(mysql_field_count(database->con) < 2)
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{
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mysql_free_result(result);
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mysql_free_result(result2);
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skygw_log_write(LE,"Error: Unexpected result for \"SHOW VARIABLES LIKE 'wsrep_sst_method'\". Expected 2 columns."
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" MySQL Version: %s",version_str);
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return;
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}
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while ((row = mysql_fetch_row(result2)))
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{
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if (strncmp(row[1], "xtrabackup", 10) == 0)
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isjoined = 1;
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}
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mysql_free_result(result2);
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}
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}
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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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if(mysql_field_count(database->con) < 2)
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{
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mysql_free_result(result);
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skygw_log_write(LE,"Error: Unexpected result for \"SHOW STATUS LIKE 'wsrep_local_index'\". Expected 2 columns."
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" MySQL Version: %s",version_str);
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return;
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}
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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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MONITOR* mon = (MONITOR*)arg;
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GALERA_MONITOR *handle;
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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;
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int is_cluster=0;
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int log_no_members = 1;
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monitor_event_t evtype;
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spinlock_acquire(&mon->lock);
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handle = (GALERA_MONITOR *)mon->handle;
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spinlock_release(&mon->lock);
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master_stickiness = handle->disableMasterFailback;
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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)%mon->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 = mon->databases;
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while (ptr)
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{
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ptr->mon_prev_status = ptr->server->status;
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monitorDatabase(mon, ptr);
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/* clear bits for non member nodes */
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if ( ! SERVER_IN_MAINT(ptr->server) && (! 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 */
|
|
server_clear_status(ptr->server, SERVER_MASTER_STICKINESS);
|
|
}
|
|
|
|
/* Log server status change */
|
|
if (mon_status_changed(ptr))
|
|
{
|
|
LOGIF(LD, (skygw_log_write_flush(
|
|
LOGFILE_DEBUG,
|
|
"Backend server %s:%d state : %s",
|
|
ptr->server->name,
|
|
ptr->server->port,
|
|
STRSRVSTATUS(ptr->server))));
|
|
}
|
|
|
|
if (!(SERVER_IS_RUNNING(ptr->server)) ||
|
|
!(SERVER_IS_IN_CLUSTER(ptr->server)))
|
|
{
|
|
dcb_call_foreach(ptr->server,DCB_REASON_NOT_RESPONDING);
|
|
}
|
|
|
|
if (SERVER_IS_DOWN(ptr->server))
|
|
{
|
|
/** Increase this server'e error count */
|
|
dcb_call_foreach(ptr->server,DCB_REASON_NOT_RESPONDING);
|
|
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, following MIN(node_id) rule */
|
|
candidate_master = get_candidate_master(mon);
|
|
|
|
/* Select the master, based on master_stickiness */
|
|
if (1 == handle->disableMasterRoleSetting) {
|
|
handle->master = NULL;
|
|
}
|
|
else {
|
|
handle->master = set_cluster_master(handle->master, candidate_master, master_stickiness);
|
|
}
|
|
|
|
ptr = mon->databases;
|
|
|
|
while (ptr) {
|
|
if (!SERVER_IS_JOINED(ptr->server) || SERVER_IN_MAINT(ptr->server)) {
|
|
ptr = ptr->next;
|
|
continue;
|
|
}
|
|
|
|
if (handle->master) {
|
|
if (ptr != handle->master) {
|
|
/* set the Slave role */
|
|
server_set_status(ptr->server, SERVER_SLAVE);
|
|
server_clear_status(ptr->server, SERVER_MASTER);
|
|
|
|
/* clear master stickiness */
|
|
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 stickiness */
|
|
server_set_status(handle->master->server, SERVER_MASTER_STICKINESS);
|
|
} else {
|
|
/* clear master stickiness */
|
|
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;
|
|
}
|
|
}
|
|
|
|
|
|
ptr = mon->databases;
|
|
|
|
while(ptr)
|
|
{
|
|
|
|
/** Execute monitor script if a server state has changed */
|
|
if(mon_status_changed(ptr))
|
|
{
|
|
evtype = mon_get_event_type(ptr);
|
|
if(isGaleraEvent(evtype))
|
|
{
|
|
skygw_log_write(LOGFILE_TRACE,"Server changed state: %s[%s:%u]: %s",
|
|
ptr->server->unique_name,
|
|
ptr->server->name,ptr->server->port,
|
|
mon_get_event_name(ptr));
|
|
if(handle->script && handle->events[evtype])
|
|
{
|
|
monitor_launch_script(mon,ptr,handle->script);
|
|
}
|
|
}
|
|
}
|
|
ptr = ptr->next;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* 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* mon) {
|
|
MONITOR_SERVERS *moitor_servers = mon->databases;
|
|
MONITOR_SERVERS *candidate_master = NULL;
|
|
GALERA_MONITOR* handle = mon->handle;
|
|
long min_id = -1;
|
|
int minval = INT_MAX;
|
|
int currval;
|
|
char* value;
|
|
/* set min_id to the lowest value of moitor_servers->server->node_id */
|
|
while(moitor_servers) {
|
|
if (!SERVER_IN_MAINT(moitor_servers->server) && SERVER_IS_JOINED(moitor_servers->server)) {
|
|
|
|
moitor_servers->server->depth = 0;
|
|
|
|
if(handle->use_priority && (value = serverGetParameter(moitor_servers->server,"priority")) != NULL)
|
|
{
|
|
currval = atoi(value);
|
|
if(currval < minval && currval > 0)
|
|
{
|
|
minval = currval;
|
|
candidate_master = moitor_servers;
|
|
}
|
|
}
|
|
else if(moitor_servers->server->node_id >= 0 &&
|
|
(!handle->use_priority || /** Server priority disabled*/
|
|
candidate_master == NULL || /** No candidate chosen */
|
|
serverGetParameter(candidate_master->server,"priority") == NULL)) /** Candidate has no priority */
|
|
{
|
|
if (min_id < 0 || moitor_servers->server->node_id < min_id) {
|
|
min_id = moitor_servers->server->node_id;
|
|
candidate_master = moitor_servers;
|
|
}
|
|
}
|
|
}
|
|
moitor_servers = moitor_servers->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)
|
|
{
|
|
GALERA_MONITOR *handle = (GALERA_MONITOR *)arg;
|
|
memcpy(&handle->disableMasterFailback, &disable, sizeof(int));
|
|
}
|
|
|
|
/**
|
|
* Allow a Galera node to be in sync when Donor.
|
|
*
|
|
* When enabled, the monitor will check if the node is using xtrabackup or xtrabackup-v2
|
|
* as SST method. In that case, node will stay as synced.
|
|
*
|
|
* @param arg The handle allocated by startMonitor
|
|
* @param disable To allow sync status use 1, 0 for traditional behavior
|
|
*/
|
|
static void
|
|
availableWhenDonor(void *arg, int disable)
|
|
{
|
|
GALERA_MONITOR *handle = (GALERA_MONITOR *)arg;
|
|
memcpy(&handle->availableWhenDonor, &disable, sizeof(int));
|
|
}
|
|
|
|
static monitor_event_t galera_events[] = {
|
|
MASTER_DOWN_EVENT,
|
|
MASTER_UP_EVENT,
|
|
SLAVE_DOWN_EVENT,
|
|
SLAVE_UP_EVENT,
|
|
SERVER_DOWN_EVENT,
|
|
SERVER_UP_EVENT,
|
|
SYNCED_DOWN_EVENT,
|
|
SYNCED_UP_EVENT,
|
|
DONOR_DOWN_EVENT,
|
|
DONOR_UP_EVENT,
|
|
LOST_MASTER_EVENT,
|
|
LOST_SLAVE_EVENT,
|
|
LOST_SYNCED_EVENT,
|
|
LOST_DONOR_EVENT,
|
|
NEW_MASTER_EVENT,
|
|
NEW_SLAVE_EVENT,
|
|
NEW_SYNCED_EVENT,
|
|
NEW_DONOR_EVENT,
|
|
MAX_MONITOR_EVENT
|
|
};
|
|
/**
|
|
* Check if the Galera monitor is monitoring this event type.
|
|
* @param event Event to check
|
|
* @return True if the event is monitored, false if it is not
|
|
* */
|
|
bool isGaleraEvent(monitor_event_t event)
|
|
{
|
|
int i;
|
|
for(i = 0;galera_events[i] != MAX_MONITOR_EVENT;i++)
|
|
{
|
|
if(event == galera_events[i])
|
|
return true;
|
|
}
|
|
return false;
|
|
} |