/* * Copyright (c) 2016 MariaDB Corporation Ab * * Use of this software is governed by the Business Source License included * in the LICENSE.TXT file and at www.mariadb.com/bsl. * * Change Date: 2019-07-01 * * On the date above, in accordance with the Business Source License, use * of this software will be governed by version 2 or later of the General * Public License. */ /** * @file mysql_mon.c - A MySQL replication cluster monitor * * @verbatim * Revision History * * Date Who Description * 08/07/13 Mark Riddoch Initial implementation * 11/07/13 Mark Riddoch Addition of code to check replication status * 25/07/13 Mark Riddoch Addition of decrypt for passwords and diagnostic interface * 20/05/14 Massimiliano Pinto Addition of support for MariadDB multimaster replication setup. * New server field version_string is updated. * 28/05/14 Massimiliano Pinto Added set Id and configuration options (setInverval) * Parameters are now printed in diagnostics * 03/06/14 Mark Ridoch Add support for maintenance mode * 17/06/14 Massimiliano Pinto Addition of getServerByNodeId routine and first implementation for * depth of replication for nodes. * 23/06/14 Massimiliano Pinto Added replication consistency after replication tree computation * 27/06/14 Massimiliano Pinto Added replication pending status in monitored server, storing there * the status to update in server status field before * starting the replication consistency check. * This will also give routers a consistent "status" of all servers * 28/08/14 Massimiliano Pinto Added detectStaleMaster feature: previous detected master will be used again, even if the replication is stopped. * This means both IO and SQL threads are not working on slaves. * This option is not enabled by default. * 10/11/14 Massimiliano Pinto Addition of setNetworkTimeout for connect, read, write * 18/11/14 Massimiliano Pinto One server only in configuration becomes master. servers=server1 must * be present in mysql_mon and in router sections as well. * 08/05/15 Markus Makela Added launchable scripts * 17/10/15 Martin Brampton Change DCB callback to hangup * * @endverbatim */ #include "../mysqlmon.h" #include #include #include /** Column positions for SHOW SLAVE STATUS */ #define MYSQL55_STATUS_BINLOG_POS 5 #define MYSQL55_STATUS_BINLOG_NAME 6 #define MYSQL55_STATUS_IO_RUNNING 10 #define MYSQL55_STATUS_SQL_RUNNING 11 #define MYSQL55_STATUS_MASTER_ID 39 /** Column positions for SHOW SLAVE STATUS */ #define MARIA10_STATUS_BINLOG_NAME 7 #define MARIA10_STATUS_BINLOG_POS 8 #define MARIA10_STATUS_IO_RUNNING 12 #define MARIA10_STATUS_SQL_RUNNING 13 #define MARIA10_STATUS_MASTER_ID 41 /** Column positions for SHOW SLAVE HOSTS */ #define SLAVE_HOSTS_SERVER_ID 0 #define SLAVE_HOSTS_HOSTNAME 1 #define SLAVE_HOSTS_PORT 2 static void monitorMain(void *); static char *version_str = "V1.5.0"; /* @see function load_module in load_utils.c for explanation of the following * lint directives. */ /*lint -e14 */ MODULE_INFO info = { MODULE_API_MONITOR, MODULE_GA, MONITOR_VERSION, "A MySQL Master/Slave replication monitor" }; /*lint +e14 */ static void *startMonitor(MONITOR *, const CONFIG_PARAMETER*); static void stopMonitor(MONITOR *); static void diagnostics(DCB *, const MONITOR *); static MONITOR_SERVERS *getServerByNodeId(MONITOR_SERVERS *, long); static MONITOR_SERVERS *getSlaveOfNodeId(MONITOR_SERVERS *, long); static MONITOR_SERVERS *get_replication_tree(MONITOR *, int); static void set_master_heartbeat(MYSQL_MONITOR *, MONITOR_SERVERS *); static void set_slave_heartbeat(MONITOR *, MONITOR_SERVERS *); static int add_slave_to_master(long *, int, long); static bool isMySQLEvent(monitor_event_t event); void check_maxscale_schema_replication(MONITOR *monitor); static bool report_version_err = true; static const char* hb_table_name = "maxscale_schema.replication_heartbeat"; static MONITOR_OBJECT MyObject = { startMonitor, stopMonitor, diagnostics }; /** * Implementation of the mandatory version entry point * * @return version string of the module * * @see function load_module in load_utils.c for explanation of the following * lint directives. */ /*lint -e14 */ char * version() { return version_str; } /** * The module initialisation routine, called when the module * is first loaded. */ void ModuleInit() { MXS_NOTICE("Initialise the MySQL Monitor module %s.", version_str); } /** * The module entry point routine. It is this routine that * must populate the structure that is referred to as the * "module object", this is a structure with the set of * external entry points for this module. * * @return The module object */ MONITOR_OBJECT * GetModuleObject() { return &MyObject; } /** * Monitor specific information about a server */ typedef struct mysql_server_info { int server_id; /**< Value of @@server_id */ int master_id; /**< Master server id from SHOW SLAVE STATUS*/ int group; /**< Multi-master group where this server belongs, 0 for servers not in groups */ bool read_only; /**< Value of @@read_only */ bool slave_configured; /**< Whether SHOW SLAVE STATUS returned rows */ bool slave_io; /**< If Slave IO thread is running */ bool slave_sql; /**< If Slave SQL thread is running */ uint64_t binlog_pos; /**< Binlog position from SHOW SLAVE STATUS */ char *binlog_name; /**< Binlog name from SHOW SLAVE STATUS */ } MYSQL_SERVER_INFO; /** Other values are implicitly zero initialized */ #define MYSQL_SERVER_INFO_INIT {.binlog_name = ""} void* info_copy_func(const void *val) { ss_dassert(val); MYSQL_SERVER_INFO *old_val = (MYSQL_SERVER_INFO*)val; MYSQL_SERVER_INFO *new_val = MXS_MALLOC(sizeof(MYSQL_SERVER_INFO)); char *binlog_name = MXS_STRDUP(old_val->binlog_name); if (new_val && binlog_name) { *new_val = *old_val; new_val->binlog_name = binlog_name; } else { MXS_FREE(new_val); MXS_FREE(binlog_name); new_val = NULL; } return new_val; } void info_free_func(void *val) { if (val) { MYSQL_SERVER_INFO *old_val = (MYSQL_SERVER_INFO*)val; MXS_FREE(old_val->binlog_name); MXS_FREE(old_val); } } /** * @brief Helper function that initializes the server info hashtable * * @param handle MySQL monitor handle * @param database List of monitored databases * @return True on success, false if initialization failed. At the moment * initialization can only fail if memory allocation fails. */ bool init_server_info(MYSQL_MONITOR *handle, MONITOR_SERVERS *database) { MYSQL_SERVER_INFO info = MYSQL_SERVER_INFO_INIT; bool rval = true; while (database) { /** Delete any existing structures and replace them with empty ones */ hashtable_delete(handle->server_info, database->server); if (!hashtable_add(handle->server_info, database->server->unique_name, &info)) { rval = false; break; } database = database->next; } return rval; } /*lint +e14 */ /** * Start the instance of the monitor, returning a handle on the monitor. * * This function creates a thread to execute the actual monitoring. * * @param arg The current handle - NULL if first start * @param opt Configuration parameters * @return A handle to use when interacting with the monitor */ static void * startMonitor(MONITOR *monitor, const CONFIG_PARAMETER* params) { MYSQL_MONITOR *handle = (MYSQL_MONITOR*) monitor->handle; bool have_events = false, script_error = false, error = false; if (handle) { handle->shutdown = 0; } else { handle = (MYSQL_MONITOR *) MXS_MALLOC(sizeof(MYSQL_MONITOR)); HASHTABLE *server_info = hashtable_alloc(MAX_NUM_SLAVES, hashtable_item_strhash, hashtable_item_strcmp); if (handle == NULL || server_info == NULL) { MXS_FREE(handle); hashtable_free(server_info); return NULL; } hashtable_memory_fns(server_info, hashtable_item_strdup, info_copy_func, hashtable_item_free, info_free_func); handle->server_info = server_info; handle->shutdown = 0; handle->id = config_get_gateway_id(); handle->replicationHeartbeat = 0; handle->detectStaleMaster = true; handle->detectStaleSlave = true; handle->master = NULL; handle->script = NULL; handle->multimaster = false; handle->mysql51_replication = false; memset(handle->events, false, sizeof(handle->events)); spinlock_init(&handle->lock); } while (params) { if (!strcmp(params->name, "detect_stale_master")) { handle->detectStaleMaster = config_truth_value(params->value); } else if (!strcmp(params->name, "detect_stale_slave")) { handle->detectStaleSlave = config_truth_value(params->value); } else if (!strcmp(params->name, "detect_replication_lag")) { handle->replicationHeartbeat = config_truth_value(params->value); } else if (!strcmp(params->name, "multimaster")) { handle->multimaster = config_truth_value(params->value); } else if (!strcmp(params->name, "script")) { if (externcmd_can_execute(params->value)) { MXS_FREE(handle->script); handle->script = MXS_STRDUP_A(params->value); } else { script_error = true; } } else if (!strcmp(params->name, "events")) { if (mon_parse_event_string((bool *)handle->events, sizeof(handle->events), params->value) != 0) { script_error = true; } else { have_events = true; } } else if (!strcmp(params->name, "mysql51_replication")) { handle->mysql51_replication = config_truth_value(params->value); } params = params->next; } if (!check_monitor_permissions(monitor, "SHOW SLAVE STATUS")) { MXS_ERROR("Failed to start monitor. See earlier errors for more information."); error = true; } if (script_error) { MXS_ERROR("[%s] Errors were found in the script configuration parameters ", monitor->name); error = true; } else if (!have_events) { /** If no specific events are given, enable them all */ memset(handle->events, true, sizeof(handle->events)); } if (!init_server_info(handle, monitor->databases)) { error = true; } if (error) { hashtable_free(handle->server_info); MXS_FREE(handle->script); MXS_FREE(handle); } else if (thread_start(&handle->thread, monitorMain, monitor) == NULL) { MXS_ERROR("Failed to start monitor thread for monitor '%s'.", monitor->name); } return handle; } /** * Stop a running monitor * * @param arg Handle on thr running monior */ static void stopMonitor(MONITOR *mon) { MYSQL_MONITOR *handle = (MYSQL_MONITOR *) mon->handle; handle->shutdown = 1; thread_wait(handle->thread); } /** * Daignostic interface * * @param dcb DCB to print diagnostics * @param arg The monitor handle */ static void diagnostics(DCB *dcb, const MONITOR *mon) { const MYSQL_MONITOR *handle = (const MYSQL_MONITOR *) mon->handle; MONITOR_SERVERS *db; char *sep; switch (handle->status) { case MONITOR_RUNNING: dcb_printf(dcb, "\tMonitor running\n"); break; case MONITOR_STOPPING: dcb_printf(dcb, "\tMonitor stopping\n"); break; case MONITOR_STOPPED: dcb_printf(dcb, "\tMonitor stopped\n"); break; } dcb_printf(dcb, "\tSampling interval:\t%lu milliseconds\n", mon->interval); dcb_printf(dcb, "\tMaxScale MonitorId:\t%lu\n", handle->id); dcb_printf(dcb, "\tReplication lag:\t%s\n", (handle->replicationHeartbeat == 1) ? "enabled" : "disabled"); dcb_printf(dcb, "\tDetect Stale Master:\t%s\n", (handle->detectStaleMaster == 1) ? "enabled" : "disabled"); dcb_printf(dcb, "\tConnect Timeout:\t%i seconds\n", mon->connect_timeout); dcb_printf(dcb, "\tRead Timeout:\t\t%i seconds\n", mon->read_timeout); dcb_printf(dcb, "\tWrite Timeout:\t\t%i seconds\n", mon->write_timeout); dcb_printf(dcb, "\nMonitored servers\n\n"); db = mon->databases; while (db) { MYSQL_SERVER_INFO *serv_info = hashtable_fetch(handle->server_info, db->server->unique_name); dcb_printf(dcb, "Server: %s\n", db->server->unique_name); dcb_printf(dcb, "Server ID: %d\n", serv_info->server_id); dcb_printf(dcb, "Read only: %s\n", serv_info->read_only ? "ON" : "OFF"); dcb_printf(dcb, "Slave configured: %s\n", serv_info->slave_configured ? "YES" : "NO"); dcb_printf(dcb, "Slave IO running: %s\n", serv_info->slave_io ? "YES" : "NO"); dcb_printf(dcb, "Slave SQL running: %s\n", serv_info->slave_sql ? "YES" : "NO"); dcb_printf(dcb, "Master ID: %d\n", serv_info->master_id); dcb_printf(dcb, "Master binlog file: %s\n", serv_info->binlog_name); dcb_printf(dcb, "Master binlog position: %lu\n", serv_info->binlog_pos); if (handle->multimaster) { dcb_printf(dcb, "Master group: %d\n", serv_info->group); } dcb_printf(dcb, "\n"); db = db->next; } } enum mysql_server_version { MYSQL_SERVER_VERSION_100, MYSQL_SERVER_VERSION_55, MYSQL_SERVER_VERSION_51 }; static inline void monitor_mysql_db(MONITOR_SERVERS* database, MYSQL_SERVER_INFO *serv_info, enum mysql_server_version server_version) { int columns, i_io_thread, i_sql_thread, i_binlog_pos, i_master_id, i_binlog_name; const char *query; if (server_version == MYSQL_SERVER_VERSION_100) { columns = 42; query = "SHOW ALL SLAVES STATUS"; i_io_thread = MARIA10_STATUS_IO_RUNNING; i_sql_thread = MARIA10_STATUS_SQL_RUNNING; i_binlog_name = MARIA10_STATUS_BINLOG_NAME; i_binlog_pos = MARIA10_STATUS_BINLOG_POS; i_master_id = MARIA10_STATUS_MASTER_ID; } else { columns = server_version == MYSQL_SERVER_VERSION_55 ? 40 : 38; query = "SHOW SLAVE STATUS"; i_io_thread = MYSQL55_STATUS_IO_RUNNING; i_sql_thread = MYSQL55_STATUS_SQL_RUNNING; i_binlog_name = MYSQL55_STATUS_BINLOG_NAME; i_binlog_pos = MYSQL55_STATUS_BINLOG_POS; i_master_id = MYSQL55_STATUS_MASTER_ID; } /** Clear old states */ monitor_clear_pending_status(database, SERVER_SLAVE | SERVER_MASTER | SERVER_RELAY_MASTER | SERVER_STALE_STATUS | SERVER_SLAVE_OF_EXTERNAL_MASTER); MYSQL_RES* result; if (mysql_query(database->con, query) == 0 && (result = mysql_store_result(database->con)) != NULL) { if (mysql_field_count(database->con) < columns) { mysql_free_result(result); MXS_ERROR("\"%s\" returned less than the expected amount of columns. " "Expected %d columns. MySQL Version: %s", query, columns, version_str); return; } MYSQL_ROW row = mysql_fetch_row(result); long master_id = -1; if (row) { serv_info->slave_configured = true; int nconfigured = 0; int nrunning = 0; do { /* get Slave_IO_Running and Slave_SQL_Running values*/ serv_info->slave_io = strncmp(row[i_io_thread], "Yes", 3) == 0; serv_info->slave_sql = strncmp(row[i_sql_thread], "Yes", 3) == 0; if (serv_info->slave_io && serv_info->slave_sql) { if (nrunning == 0) { /** Only check binlog name for the first running slave */ char *binlog_name = MXS_STRDUP(row[i_binlog_name]); if (binlog_name) { MXS_FREE(serv_info->binlog_name); serv_info->binlog_name = binlog_name; serv_info->binlog_pos = atol(row[i_binlog_pos]); } } nrunning++; } /* If Slave_IO_Running = Yes, assign the master_id to current server: this allows building * the replication tree, slaves ids will be added to master(s) and we will have at least the * root master server. * Please note, there could be no slaves at all if Slave_SQL_Running == 'No' */ if (serv_info->slave_io && server_version != MYSQL_SERVER_VERSION_51) { /* Get Master_Server_Id */ master_id = atol(row[i_master_id]); if (master_id == 0) { master_id = -1; } } nconfigured++; row = mysql_fetch_row(result); } while (row); /* If all configured slaves are running set this node as slave */ if (nrunning > 0 && nrunning == nconfigured) { monitor_set_pending_status(database, SERVER_SLAVE); } } else { /** Query returned no rows, replication is not configured */ serv_info->slave_configured = false; serv_info->slave_io = false; serv_info->slave_sql = false; serv_info->binlog_pos = 0; serv_info->binlog_name[0] = '\0'; } /** Store master_id of current node. For MySQL 5.1 it will be set at a later point. */ database->server->master_id = master_id; serv_info->master_id = master_id; mysql_free_result(result); } } /** * Build the replication tree for a MySQL 5.1 cluster * * This function queries each server with SHOW SLAVE HOSTS to determine which servers * have slaves replicating from them. * @param mon Monitor * @return Lowest server ID master in the monitor */ static MONITOR_SERVERS *build_mysql51_replication_tree(MONITOR *mon) { MONITOR_SERVERS* database = mon->databases; MONITOR_SERVERS *ptr, *rval = NULL; int i; while (database) { bool ismaster = false; MYSQL_RES* result; MYSQL_ROW row; int nslaves = 0; if (database->con) { if (mysql_query(database->con, "SHOW SLAVE HOSTS") == 0 && (result = mysql_store_result(database->con)) != NULL) { if (mysql_field_count(database->con) < 4) { mysql_free_result(result); MXS_ERROR("\"SHOW SLAVE HOSTS\" " "returned less than the expected amount of columns. " "Expected 4 columns. MySQL Version: %s", version_str); return NULL; } if (mysql_num_rows(result) > 0) { ismaster = true; while (nslaves < MAX_NUM_SLAVES && (row = mysql_fetch_row(result))) { /* get Slave_IO_Running and Slave_SQL_Running values*/ database->server->slaves[nslaves] = atol(row[SLAVE_HOSTS_SERVER_ID]); nslaves++; MXS_DEBUG("Found slave at %s:%s", row[SLAVE_HOSTS_HOSTNAME], row[SLAVE_HOSTS_PORT]); } database->server->slaves[nslaves] = 0; } mysql_free_result(result); } /* Set the Slave Role */ if (ismaster) { MXS_DEBUG("Master server found at %s:%d with %d slaves", database->server->name, database->server->port, nslaves); monitor_set_pending_status(database, SERVER_MASTER); if (rval == NULL || rval->server->node_id > database->server->node_id) { rval = database; } } } database = database->next; } database = mon->databases; /** Set master server IDs */ while (database) { ptr = mon->databases; while (ptr) { for (i = 0; ptr->server->slaves[i]; i++) { if (ptr->server->slaves[i] == database->server->node_id) { database->server->master_id = ptr->server->node_id; break; } } ptr = ptr->next; } if (database->server->master_id <= 0 && SERVER_IS_SLAVE(database->server)) { monitor_set_pending_status(database, SERVER_SLAVE_OF_EXTERNAL_MASTER); } database = database->next; } return rval; } /** * Monitor an individual server * * @param handle The MySQL Monitor object * @param database The database to probe */ static void monitorDatabase(MONITOR *mon, MONITOR_SERVERS *database) { MYSQL_MONITOR* handle = mon->handle; MYSQL_ROW row; MYSQL_RES *result; char *uname = mon->user; unsigned long int server_version = 0; char *server_string; if (database->server->monuser != NULL) { uname = database->server->monuser; } if (uname == NULL) { return; } /* Don't probe servers in maintenance mode */ if (SERVER_IN_MAINT(database->server)) { return; } /** Store previous status */ database->mon_prev_status = database->server->status; if (database->con == NULL || mysql_ping(database->con) != 0) { connect_result_t rval; if ((rval = mon_connect_to_db(mon, database)) == MONITOR_CONN_OK) { server_clear_status(database->server, SERVER_AUTH_ERROR); monitor_clear_pending_status(database, SERVER_AUTH_ERROR); } else { /* The current server is not running * * Store server NOT running in server and monitor server pending struct * */ if (mysql_errno(database->con) == ER_ACCESS_DENIED_ERROR) { server_set_status(database->server, SERVER_AUTH_ERROR); monitor_set_pending_status(database, SERVER_AUTH_ERROR); } server_clear_status(database->server, SERVER_RUNNING); monitor_clear_pending_status(database, SERVER_RUNNING); /* Also clear M/S state in both server and monitor server pending struct */ server_clear_status(database->server, SERVER_SLAVE); server_clear_status(database->server, SERVER_MASTER); server_clear_status(database->server, SERVER_RELAY_MASTER); monitor_clear_pending_status(database, SERVER_SLAVE); monitor_clear_pending_status(database, SERVER_MASTER); monitor_clear_pending_status(database, SERVER_RELAY_MASTER); /* Clean addition status too */ server_clear_status(database->server, SERVER_SLAVE_OF_EXTERNAL_MASTER); server_clear_status(database->server, SERVER_STALE_STATUS); server_clear_status(database->server, SERVER_STALE_SLAVE); monitor_clear_pending_status(database, SERVER_SLAVE_OF_EXTERNAL_MASTER); monitor_clear_pending_status(database, SERVER_STALE_STATUS); monitor_clear_pending_status(database, SERVER_STALE_SLAVE); /* Log connect failure only once */ if (mon_status_changed(database) && mon_print_fail_status(database)) { mon_log_connect_error(database, rval); } return; } } /* Store current status in both server and monitor server pending struct */ server_set_status(database->server, SERVER_RUNNING); monitor_set_pending_status(database, SERVER_RUNNING); /* get server version from current server */ server_version = mysql_get_server_version(database->con); /* get server version string */ server_string = (char *) mysql_get_server_info(database->con); if (server_string) { server_set_version_string(database->server, server_string); } MYSQL_SERVER_INFO *serv_info = hashtable_fetch(handle->server_info, database->server->unique_name); ss_dassert(serv_info); /* Get server_id and read_only from current node */ if (mysql_query(database->con, "SELECT @@server_id, @@read_only") == 0 && (result = mysql_store_result(database->con)) != NULL) { long server_id = -1; if (mysql_field_count(database->con) != 2) { mysql_free_result(result); MXS_ERROR("Unexpected result for 'SELECT @@server_id, @@read_only'. Expected 2 columns." " MySQL Version: %s", version_str); return; } while ((row = mysql_fetch_row(result))) { server_id = strtol(row[0], NULL, 10); if ((errno == ERANGE && (server_id == LONG_MAX || server_id == LONG_MIN)) || (errno != 0 && server_id == 0)) { server_id = -1; } database->server->node_id = server_id; serv_info->server_id = server_id; serv_info->read_only = (row[1] && strcmp(row[1], "1") == 0); } mysql_free_result(result); } /* Check first for MariaDB 10.x.x and get status for multi-master replication */ if (server_version >= 100000) { monitor_mysql_db(database, serv_info, MYSQL_SERVER_VERSION_100); } else if (server_version >= 5 * 10000 + 5 * 100) { monitor_mysql_db(database, serv_info, MYSQL_SERVER_VERSION_55); } else { if (handle->mysql51_replication) { monitor_mysql_db(database, serv_info, MYSQL_SERVER_VERSION_51); } else if (report_version_err) { report_version_err = false; MXS_ERROR("MySQL version is lower than 5.5 and 'mysql51_replication' option is " "not enabled, replication tree cannot be resolved. To enable MySQL 5.1 replication " "detection, add 'mysql51_replication=true' to the monitor section."); } } } /** * @brief A node in a graph */ struct graph_node { int index; int lowest_index; int cycle; bool active; struct graph_node *parent; MYSQL_SERVER_INFO *info; MONITOR_SERVERS *db; }; /** * @brief Visit a node in the graph * * This function is the main function used to determine whether the node is a * part of a cycle. It is an implementation of the Tarjan's strongly connected * component algorithm. All one node cycles are ignored since normal * master-slave monitoring handles that. * * Tarjan's strongly connected component algorithm: * * https://en.wikipedia.org/wiki/Tarjan%27s_strongly_connected_components_algorithm */ static void visit_node(struct graph_node *node, struct graph_node **stack, int *stacksize, int *index, int *cycle) { /** Assign an index to this node */ node->lowest_index = node->index = *index; node->active = true; *index += 1; stack[*stacksize] = node; *stacksize += 1; if (node->parent == NULL) { /** This node does not connect to another node, it can't be a part of a cycle */ node->lowest_index = -1; } else if (node->parent->index == 0) { /** Node has not been visited */ visit_node(node->parent, stack, stacksize, index, cycle); if (node->parent->lowest_index < node->lowest_index) { /** The parent connects to a node with a lower index, this node could be a part of a cycle. */ node->lowest_index = node->parent->lowest_index; } } else if (node->parent->active) { /** This node could be a root node of the cycle */ if (node->parent->index < node->lowest_index) { /** Root node found */ node->lowest_index = node->parent->index; } } else { /** Node connects to an already connected cycle, it can't be a part of it */ node->lowest_index = -1; } if (node->active && node->parent && node->lowest_index > 0) { if (node->lowest_index == node->index && node->lowest_index == node->parent->lowest_index) { /** * Found a multi-node cycle from the graph. The cycle is formed from the * nodes with a lowest_index value equal to the lowest_index value of the * current node. Rest of the nodes on the stack are not part of a cycle * and can be discarded. */ *cycle += 1; while (*stacksize > 0) { struct graph_node *top = stack[(*stacksize) - 1]; top->active = false; if (top->lowest_index == node->lowest_index) { top->cycle = *cycle; } *stacksize -= 1; } } } else { /** Pop invalid nodes off the stack */ node->active = false; *stacksize -= 1; } } /** * @brief Find the strongly connected components in the replication tree graph * * Each replication cluster is a directed graph made out of replication * trees. If this graph has strongly connected components (more generally * cycles), it is considered a multi-master cluster due to the fact that there * are multiple nodes where the data can originate. * * Detecting the cycles in the graph allows this monitor to better understand * the relationships between the nodes. All nodes that are a part of a cycle can * be labeled as master nodes. This information will later be used to choose the * right master where the writes should go. * * This function also populates the MYSQL_SERVER_INFO structures group * member. Nodes in a group get a positive group ID where the nodes not in a * group get a group ID of 0. */ void find_graph_cycles(MYSQL_MONITOR *handle, MONITOR_SERVERS *database, int nservers) { struct graph_node graph[nservers]; struct graph_node *stack[nservers]; int nodes = 0; for (MONITOR_SERVERS *db = database; db; db = db->next) { graph[nodes].info = hashtable_fetch(handle->server_info, db->server->unique_name); graph[nodes].db = db; ss_dassert(graph[nodes].info); graph[nodes].index = graph[nodes].lowest_index = 0; graph[nodes].cycle = 0; graph[nodes].active = false; graph[nodes].parent = NULL; nodes++; } /** Build the graph */ for (int i = 0; i < nservers; i++) { if (graph[i].info->master_id > 0) { /** Found a connected node */ for (int k = 0; k < nservers; k++) { if (graph[k].info->server_id == graph[i].info->master_id) { graph[i].parent = &graph[k]; break; } } } } int index = 1; int cycle = 0; int stacksize = 0; for (int i = 0; i < nservers; i++) { if (graph[i].index == 0) { /** Index is 0, this node has not yet been visited */ visit_node(&graph[i], stack, &stacksize, &index, &cycle); } } for (int i = 0; i < nservers; i++) { graph[i].info->group = graph[i].cycle; if (graph[i].cycle > 0) { /** We have at least one cycle in the graph */ if (graph[i].info->read_only) { monitor_set_pending_status(graph[i].db, SERVER_SLAVE); monitor_clear_pending_status(graph[i].db, SERVER_MASTER); } else { monitor_set_pending_status(graph[i].db, SERVER_MASTER); monitor_clear_pending_status(graph[i].db, SERVER_SLAVE); } } else if (handle->detectStaleMaster && cycle == 0 && graph[i].db->server->status & SERVER_MASTER && (graph[i].db->pending_status & SERVER_MASTER) == 0) { /** * Stale master detection is handled here for multi-master mode. * * If we know that no cycles were found from the graph and that a * server once had the master status, replication has broken * down. These masters are assigned the stale master status allowing * them to be used as masters even if they lose their slaves. A * slave in this case can be either a normal slave or another * master. */ monitor_set_pending_status(graph[i].db, SERVER_MASTER | SERVER_STALE_STATUS); monitor_clear_pending_status(graph[i].db, SERVER_SLAVE); } } } /** * The entry point for the monitoring module thread * * @param arg The handle of the monitor */ static void monitorMain(void *arg) { MONITOR* mon = (MONITOR*) arg; MYSQL_MONITOR *handle; MONITOR_SERVERS *ptr; int replication_heartbeat; bool detect_stale_master; int num_servers = 0; MONITOR_SERVERS *root_master = NULL; size_t nrounds = 0; int log_no_master = 1; bool heartbeat_checked = false; spinlock_acquire(&mon->lock); handle = (MYSQL_MONITOR *) mon->handle; spinlock_release(&mon->lock); replication_heartbeat = handle->replicationHeartbeat; detect_stale_master = handle->detectStaleMaster; if (mysql_thread_init()) { MXS_ERROR("mysql_thread_init failed in monitor module. Exiting."); return; } handle->status = MONITOR_RUNNING; while (1) { if (handle->shutdown) { handle->status = MONITOR_STOPPING; mysql_thread_end(); handle->status = MONITOR_STOPPED; return; } /** Wait base interval */ thread_millisleep(MON_BASE_INTERVAL_MS); if (handle->replicationHeartbeat && !heartbeat_checked) { check_maxscale_schema_replication(mon); heartbeat_checked = true; } /** * Calculate how far away the monitor interval is from its full * cycle and if monitor interval time further than the base * interval, then skip monitoring checks. Excluding the first * round. */ if (nrounds != 0 && ((nrounds * MON_BASE_INTERVAL_MS) % mon->interval) >= MON_BASE_INTERVAL_MS) { nrounds += 1; continue; } nrounds += 1; /* reset num_servers */ num_servers = 0; /* start from the first server in the list */ ptr = mon->databases; while (ptr) { ptr->mon_prev_status = ptr->server->status; /* copy server status into monitor pending_status */ ptr->pending_status = ptr->server->status; /* monitor current node */ monitorDatabase(mon, ptr); /* reset the slave list of current node */ memset(&ptr->server->slaves, 0, sizeof(ptr->server->slaves)); num_servers++; if (mon_status_changed(ptr)) { if (SRV_MASTER_STATUS(ptr->mon_prev_status)) { /** Master failed, can't recover */ MXS_NOTICE("Server %s:%d lost the master status.", ptr->server->name, ptr->server->port); } /** * Here we say: If the server's state changed * so that it isn't running or some other way * lost cluster membership, call call-back function * of every DCB for which such callback was * registered for this kind of issue (DCB_REASON_...) */ if (!(SERVER_IS_RUNNING(ptr->server)) || !(SERVER_IS_IN_CLUSTER(ptr->server))) { dcb_hangup_foreach(ptr->server); } } if (mon_status_changed(ptr)) { #if defined(SS_DEBUG) MXS_INFO("Backend server %s:%d state : %s", ptr->server->name, ptr->server->port, STRSRVSTATUS(ptr->server)); #else MXS_DEBUG("Backend server %s:%d state : %s", ptr->server->name, ptr->server->port, STRSRVSTATUS(ptr->server)); #endif } 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; } ptr = mon->databases; /* if only one server is configured, that's is Master */ if (num_servers == 1) { if (SERVER_IS_RUNNING(ptr->server)) { ptr->server->depth = 0; /* status cleanup */ monitor_clear_pending_status(ptr, SERVER_SLAVE); /* master status set */ monitor_set_pending_status(ptr, SERVER_MASTER); ptr->server->depth = 0; handle->master = ptr; root_master = ptr; } } else { /* Compute the replication tree */ if (handle->mysql51_replication) { root_master = build_mysql51_replication_tree(mon); } else { root_master = get_replication_tree(mon, num_servers); } } if (handle->multimaster) { /** Find all the master server cycles in the cluster graph. If multiple masters are found, the servers with the read_only variable set to ON will be assigned the slave status. */ find_graph_cycles(handle, mon->databases, num_servers); } ptr = mon->databases; while (ptr) { MYSQL_SERVER_INFO *serv_info = hashtable_fetch(handle->server_info, ptr->server->unique_name); ss_dassert(serv_info); if (ptr->server->node_id > 0 && ptr->server->master_id > 0 && getSlaveOfNodeId(mon->databases, ptr->server->node_id) && getServerByNodeId(mon->databases, ptr->server->master_id) && (!handle->multimaster || serv_info->group == 0)) { /** This server is both a slave and a master i.e. a relay master */ monitor_set_pending_status(ptr, SERVER_RELAY_MASTER); monitor_clear_pending_status(ptr, SERVER_MASTER); } ptr = ptr->next; } /* Update server status from monitor pending status on that server*/ ptr = mon->databases; while (ptr) { if (!SERVER_IN_MAINT(ptr->server)) { /** If "detect_stale_master" option is On, let's use the previous master. * * Multi-master mode detects the stale masters in find_graph_cycles(). */ if (detect_stale_master && root_master && !handle->multimaster && (strcmp(ptr->server->name, root_master->server->name) == 0 && ptr->server->port == root_master->server->port) && (ptr->server->status & SERVER_MASTER) && !(ptr->pending_status & SERVER_MASTER)) { /** * In this case server->status will not be updated from pending_status * Set the STALE bit for this server in server struct */ server_set_status(ptr->server, SERVER_STALE_STATUS | SERVER_MASTER); ptr->pending_status |= SERVER_STALE_STATUS | SERVER_MASTER; /** Log the message only if the master server didn't have * the stale master bit set */ if ((ptr->mon_prev_status & SERVER_STALE_STATUS) == 0) { MXS_WARNING("All slave servers under the current master " "server have been lost. Assigning Stale Master" " status to the old master server '%s' (%s:%i).", ptr->server->unique_name, ptr->server->name, ptr->server->port); } } if (handle->detectStaleSlave) { int bits = SERVER_SLAVE | SERVER_RUNNING; if ((ptr->mon_prev_status & bits) == bits && root_master && SERVER_IS_MASTER(root_master->server)) { /** Slave with a running master, assign stale slave candidacy */ if ((ptr->pending_status & bits) == bits) { ptr->pending_status |= SERVER_STALE_SLAVE; } /** Server lost slave when a master is available, remove * stale slave candidacy */ else if ((ptr->pending_status & bits) == SERVER_RUNNING) { ptr->pending_status &= ~SERVER_STALE_SLAVE; } } /** If this server was a stale slave candidate, assign * slave status to it */ else if (ptr->mon_prev_status & SERVER_STALE_SLAVE && ptr->pending_status & SERVER_RUNNING && // Master is down (!root_master || !SERVER_IS_MASTER(root_master->server) || // Master just came up (SERVER_IS_MASTER(root_master->server) && (root_master->mon_prev_status & SERVER_MASTER) == 0))) { ptr->pending_status |= SERVER_SLAVE; } } ptr->server->status = ptr->pending_status; } ptr = ptr->next; } ptr = mon->databases; monitor_event_t evtype; while (ptr) { /** Execute monitor script if a server state has changed */ if (mon_status_changed(ptr)) { evtype = mon_get_event_type(ptr); if (isMySQLEvent(evtype)) { mon_log_state_change(ptr); if (handle->script && handle->events[evtype]) { monitor_launch_script(mon, ptr, handle->script); } } } ptr = ptr->next; } /* log master detection failure of first master becomes available after failure */ if (root_master && mon_status_changed(root_master) && !(root_master->server->status & SERVER_STALE_STATUS)) { if (root_master->pending_status & (SERVER_MASTER) && SERVER_IS_RUNNING(root_master->server)) { if (!(root_master->mon_prev_status & SERVER_STALE_STATUS) && !(root_master->server->status & SERVER_MAINT)) { MXS_NOTICE("A Master Server is now available: %s:%i", root_master->server->name, root_master->server->port); } } else { MXS_ERROR("No Master can be determined. Last known was %s:%i", root_master->server->name, root_master->server->port); } log_no_master = 1; } else { if (!root_master && log_no_master) { MXS_ERROR("No Master can be determined"); log_no_master = 0; } } /* Do now the heartbeat replication set/get for MySQL Replication Consistency */ if (replication_heartbeat && root_master && (SERVER_IS_MASTER(root_master->server) || SERVER_IS_RELAY_SERVER(root_master->server))) { set_master_heartbeat(handle, root_master); ptr = mon->databases; while (ptr) { if ((!SERVER_IN_MAINT(ptr->server)) && SERVER_IS_RUNNING(ptr->server)) { if (ptr->server->node_id != root_master->server->node_id && (SERVER_IS_SLAVE(ptr->server) || SERVER_IS_RELAY_SERVER(ptr->server))) { set_slave_heartbeat(mon, ptr); } } ptr = ptr->next; } } } /*< while (1) */ } /** * Fetch a MySQL node by node_id * * @param ptr The list of servers to monitor * @param node_id The MySQL server_id to fetch * @return The server with the required server_id */ static MONITOR_SERVERS * getServerByNodeId(MONITOR_SERVERS *ptr, long node_id) { SERVER *current; while (ptr) { current = ptr->server; if (current->node_id == node_id) { return ptr; } ptr = ptr->next; } return NULL; } /** * Fetch a MySQL slave node from a node_id * * @param ptr The list of servers to monitor * @param node_id The MySQL server_id to fetch * @return The slave server of this node_id */ static MONITOR_SERVERS * getSlaveOfNodeId(MONITOR_SERVERS *ptr, long node_id) { SERVER *current; while (ptr) { current = ptr->server; if (current->master_id == node_id) { return ptr; } ptr = ptr->next; } return NULL; } /******* * This function sets the replication heartbeat * into the maxscale_schema.replication_heartbeat table in the current master. * The inserted values will be seen from all slaves replication from this master. * * @param handle The monitor handle * @param database The number database server */ static void set_master_heartbeat(MYSQL_MONITOR *handle, MONITOR_SERVERS *database) { unsigned long id = handle->id; time_t heartbeat; time_t purge_time; char heartbeat_insert_query[512] = ""; char heartbeat_purge_query[512] = ""; if (handle->master == NULL) { MXS_ERROR("[mysql_mon]: set_master_heartbeat called without an available Master server"); return; } /* create the maxscale_schema database */ if (mysql_query(database->con, "CREATE DATABASE IF NOT EXISTS maxscale_schema")) { MXS_ERROR("[mysql_mon]: Error creating maxscale_schema database in Master server" ": %s", mysql_error(database->con)); database->server->rlag = -1; } /* create repl_heartbeat table in maxscale_schema database */ if (mysql_query(database->con, "CREATE TABLE IF NOT EXISTS " "maxscale_schema.replication_heartbeat " "(maxscale_id INT NOT NULL, " "master_server_id INT NOT NULL, " "master_timestamp INT UNSIGNED NOT NULL, " "PRIMARY KEY ( master_server_id, maxscale_id ) ) " "ENGINE=MYISAM DEFAULT CHARSET=latin1")) { MXS_ERROR("[mysql_mon]: Error creating maxscale_schema.replication_heartbeat " "table in Master server: %s", mysql_error(database->con)); database->server->rlag = -1; } /* auto purge old values after 48 hours*/ purge_time = time(0) - (3600 * 48); sprintf(heartbeat_purge_query, "DELETE FROM maxscale_schema.replication_heartbeat WHERE master_timestamp < %lu", purge_time); if (mysql_query(database->con, heartbeat_purge_query)) { MXS_ERROR("[mysql_mon]: Error deleting from maxscale_schema.replication_heartbeat " "table: [%s], %s", heartbeat_purge_query, mysql_error(database->con)); } heartbeat = time(0); /* set node_ts for master as time(0) */ database->server->node_ts = heartbeat; sprintf(heartbeat_insert_query, "UPDATE maxscale_schema.replication_heartbeat SET master_timestamp = %lu WHERE master_server_id = %li AND maxscale_id = %lu", heartbeat, handle->master->server->node_id, id); /* Try to insert MaxScale timestamp into master */ if (mysql_query(database->con, heartbeat_insert_query)) { database->server->rlag = -1; MXS_ERROR("[mysql_mon]: Error updating maxscale_schema.replication_heartbeat table: [%s], %s", heartbeat_insert_query, mysql_error(database->con)); } else { if (mysql_affected_rows(database->con) == 0) { heartbeat = time(0); sprintf(heartbeat_insert_query, "REPLACE INTO maxscale_schema.replication_heartbeat (master_server_id, maxscale_id, master_timestamp ) VALUES ( %li, %lu, %lu)", handle->master->server->node_id, id, heartbeat); if (mysql_query(database->con, heartbeat_insert_query)) { database->server->rlag = -1; MXS_ERROR("[mysql_mon]: Error inserting into " "maxscale_schema.replication_heartbeat table: [%s], %s", heartbeat_insert_query, mysql_error(database->con)); } else { /* Set replication lag to 0 for the master */ database->server->rlag = 0; MXS_DEBUG("[mysql_mon]: heartbeat table inserted data for %s:%i", database->server->name, database->server->port); } } else { /* Set replication lag as 0 for the master */ database->server->rlag = 0; MXS_DEBUG("[mysql_mon]: heartbeat table updated for Master %s:%i", database->server->name, database->server->port); } } } /******* * This function gets the replication heartbeat * from the maxscale_schema.replication_heartbeat table in the current slave * and stores the timestamp and replication lag in the slave server struct * * @param handle The monitor handle * @param database The number database server */ static void set_slave_heartbeat(MONITOR* mon, MONITOR_SERVERS *database) { MYSQL_MONITOR *handle = (MYSQL_MONITOR*) mon->handle; unsigned long id = handle->id; time_t heartbeat; char select_heartbeat_query[256] = ""; MYSQL_ROW row; MYSQL_RES *result; if (handle->master == NULL) { MXS_ERROR("[mysql_mon]: set_slave_heartbeat called without an available Master server"); return; } /* Get the master_timestamp value from maxscale_schema.replication_heartbeat table */ sprintf(select_heartbeat_query, "SELECT master_timestamp " "FROM maxscale_schema.replication_heartbeat " "WHERE maxscale_id = %lu AND master_server_id = %li", id, handle->master->server->node_id); /* if there is a master then send the query to the slave with master_id */ if (handle->master != NULL && (mysql_query(database->con, select_heartbeat_query) == 0 && (result = mysql_store_result(database->con)) != NULL)) { int rows_found = 0; while ((row = mysql_fetch_row(result))) { int rlag = -1; time_t slave_read; rows_found = 1; heartbeat = time(0); slave_read = strtoul(row[0], NULL, 10); if ((errno == ERANGE && (slave_read == LONG_MAX || slave_read == LONG_MIN)) || (errno != 0 && slave_read == 0)) { slave_read = 0; } if (slave_read) { /* set the replication lag */ rlag = heartbeat - slave_read; } /* set this node_ts as master_timestamp read from replication_heartbeat table */ database->server->node_ts = slave_read; if (rlag >= 0) { /* store rlag only if greater than monitor sampling interval */ database->server->rlag = ((unsigned int)rlag > (mon->interval / 1000)) ? rlag : 0; } else { database->server->rlag = -1; } MXS_DEBUG("Slave %s:%i has %i seconds lag", database->server->name, database->server->port, database->server->rlag); } if (!rows_found) { database->server->rlag = -1; database->server->node_ts = 0; } mysql_free_result(result); } else { database->server->rlag = -1; database->server->node_ts = 0; if (handle->master->server->node_id < 0) { MXS_ERROR("[mysql_mon]: error: replication heartbeat: " "master_server_id NOT available for %s:%i", database->server->name, database->server->port); } else { MXS_ERROR("[mysql_mon]: error: replication heartbeat: " "failed selecting from hearthbeat table of %s:%i : [%s], %s", database->server->name, database->server->port, select_heartbeat_query, mysql_error(database->con)); } } } /******* * This function computes the replication tree * from a set of MySQL Master/Slave monitored servers * and returns the root server with SERVER_MASTER bit. * The tree is computed even for servers in 'maintenance' mode. * * @param handle The monitor handle * @param num_servers The number of servers monitored * @return The server at root level with SERVER_MASTER bit */ static MONITOR_SERVERS *get_replication_tree(MONITOR *mon, int num_servers) { MYSQL_MONITOR* handle = (MYSQL_MONITOR*) mon->handle; MONITOR_SERVERS *ptr; MONITOR_SERVERS *backend; SERVER *current; int depth = 0; long node_id; int root_level; ptr = mon->databases; root_level = num_servers; while (ptr) { /* The server could be in SERVER_IN_MAINT * that means SERVER_IS_RUNNING returns 0 * Let's check only for SERVER_IS_DOWN: server is not running */ if (SERVER_IS_DOWN(ptr->server)) { ptr = ptr->next; continue; } depth = 0; current = ptr->server; node_id = current->master_id; if (node_id < 1) { MONITOR_SERVERS *find_slave; find_slave = getSlaveOfNodeId(mon->databases, current->node_id); if (find_slave == NULL) { current->depth = -1; ptr = ptr->next; continue; } else { current->depth = 0; } } else { depth++; } while (depth <= num_servers) { /* set the root master at lowest depth level */ if (current->depth > -1 && current->depth < root_level) { root_level = current->depth; handle->master = ptr; } backend = getServerByNodeId(mon->databases, node_id); if (backend) { node_id = backend->server->master_id; } else { node_id = -1; } if (node_id > 0) { current->depth = depth + 1; depth++; } else { MONITOR_SERVERS *master; current->depth = depth; master = getServerByNodeId(mon->databases, current->master_id); if (master && master->server && master->server->node_id > 0) { add_slave_to_master(master->server->slaves, sizeof(master->server->slaves), current->node_id); master->server->depth = current->depth - 1; if(handle->master && master->server->depth < handle->master->server->depth) { /** A master with a lower depth was found, remove the master status from the previous master. */ monitor_clear_pending_status(handle->master, SERVER_MASTER); } monitor_set_pending_status(master, SERVER_MASTER); handle->master = master; } else { if (current->master_id > 0) { /* this server is slave of another server not in MaxScale configuration * we cannot use it as a real slave. */ monitor_clear_pending_status(ptr, SERVER_SLAVE); monitor_set_pending_status(ptr, SERVER_SLAVE_OF_EXTERNAL_MASTER); } } break; } } ptr = ptr->next; } /* * Return the root master */ if (handle->master != NULL) { /* If the root master is in MAINT, return NULL */ if (SERVER_IN_MAINT(handle->master->server)) { return NULL; } else { return handle->master; } } else { return NULL; } } /******* * This function add a slave id into the slaves server field * of its master server * * @param slaves_list The slave list array of the master server * @param list_size The size of the slave list * @param node_id The node_id of the slave to be inserted * @return 1 for inserted value and 0 otherwise */ static int add_slave_to_master(long *slaves_list, int list_size, long node_id) { for (int i = 0; i < list_size; i++) { if (slaves_list[i] == 0) { slaves_list[i] = node_id; return 1; } } return 0; } static monitor_event_t mysql_events[] = { MASTER_DOWN_EVENT, MASTER_UP_EVENT, SLAVE_DOWN_EVENT, SLAVE_UP_EVENT, SERVER_DOWN_EVENT, SERVER_UP_EVENT, LOST_MASTER_EVENT, LOST_SLAVE_EVENT, NEW_MASTER_EVENT, NEW_SLAVE_EVENT, MAX_MONITOR_EVENT }; /** * Check if the MySQL monitor is monitoring this event type. * @param event Event to check * @return True if the event is monitored, false if it is not * */ bool isMySQLEvent(monitor_event_t event) { int i; for (i = 0; mysql_events[i] != MAX_MONITOR_EVENT; i++) { if (event == mysql_events[i]) { return true; } } return false; } /** * Check if replicate_ignore_table is defined and if maxscale_schema.replication_hearbeat * table is in the list. * @param database Server to check * @return False if the table is not replicated or an error occurred when querying * the server */ bool check_replicate_ignore_table(MONITOR_SERVERS* database) { MYSQL_RES *result; bool rval = true; if (mysql_query(database->con, "show variables like 'replicate_ignore_table'") == 0 && (result = mysql_store_result(database->con)) && mysql_num_fields(result) > 1) { MYSQL_ROW row; while ((row = mysql_fetch_row(result))) { if (strlen(row[1]) > 0 && strcasestr(row[1], hb_table_name)) { MXS_WARNING("'replicate_ignore_table' is " "defined on server '%s' and '%s' was found in it. ", database->server->unique_name, hb_table_name); rval = false; } } mysql_free_result(result); } else { MXS_ERROR("Failed to query server %s for " "'replicate_ignore_table': %s", database->server->unique_name, mysql_error(database->con)); rval = false; } return rval; } /** * Check if replicate_do_table is defined and if maxscale_schema.replication_hearbeat * table is not in the list. * @param database Server to check * @return False if the table is not replicated or an error occurred when querying * the server */ bool check_replicate_do_table(MONITOR_SERVERS* database) { MYSQL_RES *result; bool rval = true; if (mysql_query(database->con, "show variables like 'replicate_do_table'") == 0 && (result = mysql_store_result(database->con)) && mysql_num_fields(result) > 1) { MYSQL_ROW row; while ((row = mysql_fetch_row(result))) { if (strlen(row[1]) > 0 && strcasestr(row[1], hb_table_name) == NULL) { MXS_WARNING("'replicate_do_table' is " "defined on server '%s' and '%s' was not found in it. ", database->server->unique_name, hb_table_name); rval = false; } } mysql_free_result(result); } else { MXS_ERROR("Failed to query server %s for " "'replicate_do_table': %s", database->server->unique_name, mysql_error(database->con)); rval = false; } return rval; } /** * Check if replicate_wild_do_table is defined and if it doesn't match * maxscale_schema.replication_heartbeat. * @param database Database server * @return False if the table is not replicated or an error occurred when trying to * query the server. */ bool check_replicate_wild_do_table(MONITOR_SERVERS* database) { MYSQL_RES *result; bool rval = true; if (mysql_query(database->con, "show variables like 'replicate_wild_do_table'") == 0 && (result = mysql_store_result(database->con)) && mysql_num_fields(result) > 1) { MYSQL_ROW row; while ((row = mysql_fetch_row(result))) { if (strlen(row[1]) > 0) { mxs_pcre2_result_t rc = modutil_mysql_wildcard_match(row[1], hb_table_name); if (rc == MXS_PCRE2_NOMATCH) { MXS_WARNING("'replicate_wild_do_table' is " "defined on server '%s' and '%s' does not match it. ", database->server->unique_name, hb_table_name); rval = false; } } } mysql_free_result(result); } else { MXS_ERROR("Failed to query server %s for " "'replicate_wild_do_table': %s", database->server->unique_name, mysql_error(database->con)); rval = false; } return rval; } /** * Check if replicate_wild_ignore_table is defined and if it matches * maxscale_schema.replication_heartbeat. * @param database Database server * @return False if the table is not replicated or an error occurred when trying to * query the server. */ bool check_replicate_wild_ignore_table(MONITOR_SERVERS* database) { MYSQL_RES *result; bool rval = true; if (mysql_query(database->con, "show variables like 'replicate_wild_ignore_table'") == 0 && (result = mysql_store_result(database->con)) && mysql_num_fields(result) > 1) { MYSQL_ROW row; while ((row = mysql_fetch_row(result))) { if (strlen(row[1]) > 0) { mxs_pcre2_result_t rc = modutil_mysql_wildcard_match(row[1], hb_table_name); if (rc == MXS_PCRE2_MATCH) { MXS_WARNING("'replicate_wild_ignore_table' is " "defined on server '%s' and '%s' matches it. ", database->server->unique_name, hb_table_name); rval = false; } } } mysql_free_result(result); } else { MXS_ERROR("Failed to query server %s for " "'replicate_wild_do_table': %s", database->server->unique_name, mysql_error(database->con)); rval = false; } return rval; } /** * Check if the maxscale_schema.replication_heartbeat table is replicated on all * servers and log a warning if problems were found. * @param monitor Monitor structure */ void check_maxscale_schema_replication(MONITOR *monitor) { MONITOR_SERVERS* database = monitor->databases; bool err = false; while (database) { connect_result_t rval = mon_connect_to_db(monitor, database); if (rval == MONITOR_CONN_OK) { if (!check_replicate_ignore_table(database) || !check_replicate_do_table(database) || !check_replicate_wild_do_table(database) || !check_replicate_wild_ignore_table(database)) { err = true; } } else { mon_log_connect_error(database, rval); } database = database->next; } if (err) { MXS_WARNING("Problems were encountered when checking if '%s' is replicated. Make sure that " "the table is replicated to all slaves.", hb_table_name); } }