1bef791572
1. Move some remaining class data private. 2. Linebreak long lines. 3. Move current master autoselection inside class method. 4. Remove single-use constant #defines. 5. Monitor status is only written inside loop.
988 lines
33 KiB
C++
988 lines
33 KiB
C++
/*
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* Copyright (c) 2018 MariaDB Corporation Ab
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*
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* Use of this software is governed by the Business Source License included
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* in the LICENSE.TXT file and at www.mariadb.com/bsl11.
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*
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* Change Date: 2020-01-01
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*
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* On the date above, in accordance with the Business Source License, use
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* of this software will be governed by version 2 or later of the General
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* Public License.
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*/
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#include "mariadbmon.hh"
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#include <inttypes.h>
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#include <maxscale/mysql_utils.h>
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static int add_slave_to_master(long *slaves_list, int list_size, long node_id);
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static void read_server_variables(MXS_MONITORED_SERVER* database, MySqlServerInfo* serv_info);
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static bool report_version_err = true;
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/**
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* Build the replication tree for a MySQL 5.1 cluster
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*
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* This function queries each server with SHOW SLAVE HOSTS to determine which servers have slaves replicating
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* from them.
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*
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* @return Lowest server ID master in the monitor
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*/
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MXS_MONITORED_SERVER* MariaDBMonitor::build_mysql51_replication_tree()
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{
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/** Column positions for SHOW SLAVE HOSTS */
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const size_t SLAVE_HOSTS_SERVER_ID = 0;
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const size_t SLAVE_HOSTS_HOSTNAME = 1;
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const size_t SLAVE_HOSTS_PORT = 2;
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MXS_MONITORED_SERVER* database = m_monitor_base->monitored_servers;
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MXS_MONITORED_SERVER *ptr, *rval = NULL;
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int i;
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while (database)
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{
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bool ismaster = false;
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MYSQL_RES* result;
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MYSQL_ROW row;
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int nslaves = 0;
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if (database->con)
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{
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if (mxs_mysql_query(database->con, "SHOW SLAVE HOSTS") == 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) < 4)
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{
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mysql_free_result(result);
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MXS_ERROR("\"SHOW SLAVE HOSTS\" "
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"returned less than the expected amount of columns. "
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"Expected 4 columns.");
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return NULL;
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}
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if (mysql_num_rows(result) > 0)
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{
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ismaster = true;
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while (nslaves < MAX_NUM_SLAVES && (row = mysql_fetch_row(result)))
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{
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/* get Slave_IO_Running and Slave_SQL_Running values*/
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database->server->slaves[nslaves] = atol(row[SLAVE_HOSTS_SERVER_ID]);
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nslaves++;
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MXS_DEBUG("Found slave at %s:%s", row[SLAVE_HOSTS_HOSTNAME], row[SLAVE_HOSTS_PORT]);
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}
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database->server->slaves[nslaves] = 0;
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}
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mysql_free_result(result);
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}
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else
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{
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mon_report_query_error(database);
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}
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/* Set the Slave Role */
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if (ismaster)
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{
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m_master = database;
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MXS_DEBUG("Master server found at [%s]:%d with %d slaves",
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database->server->name,
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database->server->port,
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nslaves);
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monitor_set_pending_status(database, SERVER_MASTER);
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database->server->depth = 0; // Add Depth 0 for Master
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if (rval == NULL || rval->server->node_id > database->server->node_id)
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{
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rval = database;
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}
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}
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}
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database = database->next;
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}
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database = m_monitor_base->monitored_servers;
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/** Set master server IDs */
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while (database)
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{
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ptr = m_monitor_base->monitored_servers;
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while (ptr)
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{
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for (i = 0; ptr->server->slaves[i]; i++)
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{
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if (ptr->server->slaves[i] == database->server->node_id)
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{
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database->server->master_id = ptr->server->node_id;
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database->server->depth = 1; // Add Depth 1 for Slave
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break;
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}
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}
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ptr = ptr->next;
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}
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if (SERVER_IS_SLAVE(database->server) &&
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(database->server->master_id <= 0 ||
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database->server->master_id != m_master->server->node_id))
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{
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monitor_set_pending_status(database, SERVER_SLAVE);
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monitor_set_pending_status(database, SERVER_SLAVE_OF_EXTERNAL_MASTER);
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}
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database = database->next;
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}
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return rval;
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}
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/**
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* This function computes the replication tree from a set of monitored servers and returns the root server
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* with SERVER_MASTER bit. The tree is computed even for servers in 'maintenance' mode.
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*
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* @param num_servers The number of servers monitored
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* @return The server at root level with SERVER_MASTER bit
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*/
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MXS_MONITORED_SERVER* MariaDBMonitor::get_replication_tree(int num_servers)
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{
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MXS_MONITORED_SERVER *ptr;
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MXS_MONITORED_SERVER *backend;
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SERVER *current;
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int depth = 0;
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long node_id;
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int root_level;
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ptr = m_monitor_base->monitored_servers;
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root_level = num_servers;
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while (ptr)
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{
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/* The server could be in SERVER_IN_MAINT
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* that means SERVER_IS_RUNNING returns 0
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* Let's check only for SERVER_IS_DOWN: server is not running
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*/
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if (SERVER_IS_DOWN(ptr->server))
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{
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ptr = ptr->next;
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continue;
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}
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depth = 0;
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current = ptr->server;
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node_id = current->master_id;
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/** Either this node doesn't replicate from a master or the master
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* where it replicates from is not configured to this monitor. */
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if (node_id < 1 ||
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getServerByNodeId(m_monitor_base->monitored_servers, node_id) == NULL)
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{
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MXS_MONITORED_SERVER *find_slave;
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find_slave = getSlaveOfNodeId(m_monitor_base->monitored_servers, current->node_id, ACCEPT_DOWN);
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if (find_slave == NULL)
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{
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current->depth = -1;
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ptr = ptr->next;
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continue;
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}
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else
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{
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current->depth = 0;
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}
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}
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else
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{
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depth++;
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}
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while (depth <= num_servers)
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{
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/* set the root master at lowest depth level */
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if (current->depth > -1 && current->depth < root_level)
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{
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root_level = current->depth;
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m_master = ptr;
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}
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backend = getServerByNodeId(m_monitor_base->monitored_servers, node_id);
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if (backend)
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{
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node_id = backend->server->master_id;
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}
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else
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{
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node_id = -1;
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}
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if (node_id > 0)
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{
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current->depth = depth + 1;
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depth++;
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}
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else
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{
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MXS_MONITORED_SERVER *master_cand;
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current->depth = depth;
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master_cand = getServerByNodeId(m_monitor_base->monitored_servers, current->master_id);
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if (master_cand && master_cand->server && master_cand->server->node_id > 0)
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{
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add_slave_to_master(master_cand->server->slaves, sizeof(master_cand->server->slaves),
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current->node_id);
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master_cand->server->depth = current->depth - 1;
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if (m_master && master_cand->server->depth < m_master->server->depth)
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{
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/** A master with a lower depth was found, remove
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the master status from the previous master. */
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monitor_clear_pending_status(m_master, SERVER_MASTER);
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m_master = master_cand;
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}
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MySqlServerInfo* info = get_server_info(master_cand);
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if (SERVER_IS_RUNNING(master_cand->server))
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{
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/** Only set the Master status if read_only is disabled */
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monitor_set_pending_status(master_cand, info->read_only ? SERVER_SLAVE : SERVER_MASTER);
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}
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}
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else
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{
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if (current->master_id > 0)
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{
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monitor_set_pending_status(ptr, SERVER_SLAVE);
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monitor_set_pending_status(ptr, SERVER_SLAVE_OF_EXTERNAL_MASTER);
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}
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}
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break;
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}
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}
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ptr = ptr->next;
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}
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/*
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* Return the root master
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*/
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if (m_master != NULL)
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{
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/* If the root master is in MAINT, return NULL */
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if (SERVER_IN_MAINT(m_master->server))
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{
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return NULL;
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}
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else
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{
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return m_master;
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}
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}
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else
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{
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return NULL;
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}
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}
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/*******
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* This function add a slave id into the slaves server field
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* of its master server
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*
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* @param slaves_list The slave list array of the master server
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* @param list_size The size of the slave list
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* @param node_id The node_id of the slave to be inserted
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* @return 1 for inserted value and 0 otherwise
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*/
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static int add_slave_to_master(long *slaves_list, int list_size, long node_id)
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{
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for (int i = 0; i < list_size; i++)
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{
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if (slaves_list[i] == 0)
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{
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slaves_list[i] = node_id;
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return 1;
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}
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}
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return 0;
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}
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/**
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* Fetch a node by node_id
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*
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* @param ptr The list of servers to monitor
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* @param node_id The server_id to fetch
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*
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* @return The server with the required server_id
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*/
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MXS_MONITORED_SERVER* getServerByNodeId(MXS_MONITORED_SERVER *ptr, long node_id)
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{
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SERVER *current;
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while (ptr)
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{
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current = ptr->server;
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if (current->node_id == node_id)
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{
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return ptr;
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}
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ptr = ptr->next;
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}
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return NULL;
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}
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/**
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* Fetch a slave node from a node_id
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*
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* @param ptr The list of servers to monitor
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* @param node_id The server_id to fetch
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* @param slave_down_setting Whether to accept or reject slaves which are down
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* @return The slave server of this node_id
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*/
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MXS_MONITORED_SERVER* getSlaveOfNodeId(MXS_MONITORED_SERVER *ptr, long node_id,
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slave_down_setting_t slave_down_setting)
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{
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SERVER *current;
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while (ptr)
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{
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current = ptr->server;
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if (current->master_id == node_id && (slave_down_setting == ACCEPT_DOWN || !SERVER_IS_DOWN(current)))
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{
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return ptr;
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}
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ptr = ptr->next;
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}
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return NULL;
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}
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bool MariaDBMonitor::do_show_slave_status(MySqlServerInfo* serv_info, MXS_MONITORED_SERVER* database)
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{
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/** Column positions for SHOW SLAVE STATUS */
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const size_t MYSQL55_STATUS_MASTER_LOG_POS = 5;
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const size_t MYSQL55_STATUS_MASTER_LOG_FILE = 6;
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const size_t MYSQL55_STATUS_IO_RUNNING = 10;
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const size_t MYSQL55_STATUS_SQL_RUNNING = 11;
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const size_t MYSQL55_STATUS_MASTER_ID = 39;
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/** Column positions for SHOW SLAVE STATUS */
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const size_t MARIA10_STATUS_MASTER_LOG_FILE = 7;
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const size_t MARIA10_STATUS_MASTER_LOG_POS = 8;
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const size_t MARIA10_STATUS_IO_RUNNING = 12;
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const size_t MARIA10_STATUS_SQL_RUNNING = 13;
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const size_t MARIA10_STATUS_MASTER_ID = 41;
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bool rval = true;
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unsigned int columns;
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int i_slave_io_running, i_slave_sql_running, i_read_master_log_pos, i_master_server_id, i_master_log_file;
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const char *query;
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mysql_server_version server_version = serv_info->version;
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if (server_version == MYSQL_SERVER_VERSION_100)
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{
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columns = 42;
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query = "SHOW ALL SLAVES STATUS";
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i_slave_io_running = MARIA10_STATUS_IO_RUNNING;
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i_slave_sql_running = MARIA10_STATUS_SQL_RUNNING;
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i_master_log_file = MARIA10_STATUS_MASTER_LOG_FILE;
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i_read_master_log_pos = MARIA10_STATUS_MASTER_LOG_POS;
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i_master_server_id = MARIA10_STATUS_MASTER_ID;
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}
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else
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{
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columns = server_version == MYSQL_SERVER_VERSION_55 ? 40 : 38;
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query = "SHOW SLAVE STATUS";
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i_slave_io_running = MYSQL55_STATUS_IO_RUNNING;
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i_slave_sql_running = MYSQL55_STATUS_SQL_RUNNING;
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i_master_log_file = MYSQL55_STATUS_MASTER_LOG_FILE;
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i_read_master_log_pos = MYSQL55_STATUS_MASTER_LOG_POS;
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i_master_server_id = MYSQL55_STATUS_MASTER_ID;
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}
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MYSQL_RES* result;
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int64_t master_server_id = SERVER_ID_UNKNOWN;
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int nconfigured = 0;
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int nrunning = 0;
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if (mxs_mysql_query(database->con, query) == 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) < columns)
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{
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mysql_free_result(result);
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MXS_ERROR("\"%s\" returned less than the expected amount of columns. "
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"Expected %u columns.", query, columns);
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return false;
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}
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MYSQL_ROW row = mysql_fetch_row(result);
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if (row)
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{
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serv_info->slave_configured = true;
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do
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{
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/* get Slave_IO_Running and Slave_SQL_Running values*/
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serv_info->slave_status.slave_io_running = strncmp(row[i_slave_io_running], "Yes", 3) == 0;
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serv_info->slave_status.slave_sql_running = strncmp(row[i_slave_sql_running], "Yes", 3) == 0;
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if (serv_info->slave_status.slave_io_running && serv_info->slave_status.slave_sql_running)
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{
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if (nrunning == 0)
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{
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/** Only check binlog name for the first running slave */
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uint64_t read_master_log_pos = atol(row[i_read_master_log_pos]);
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char* master_log_file = row[i_master_log_file];
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if (serv_info->slave_status.master_log_file != master_log_file ||
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read_master_log_pos != serv_info->slave_status.read_master_log_pos)
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{
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// IO thread is reading events from the master
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serv_info->latest_event = time(NULL);
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}
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serv_info->slave_status.master_log_file = master_log_file;
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serv_info->slave_status.read_master_log_pos = read_master_log_pos;
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}
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nrunning++;
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}
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/* If Slave_IO_Running = Yes, assign the master_id to current server: this allows building
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* the replication tree, slaves ids will be added to master(s) and we will have at least the
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* root master server.
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* Please note, there could be no slaves at all if Slave_SQL_Running == 'No'
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*/
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const char* last_io_errno = mxs_mysql_get_value(result, row, "Last_IO_Errno");
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int io_errno = last_io_errno ? atoi(last_io_errno) : 0;
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const int connection_errno = 2003;
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if ((io_errno == 0 || io_errno == connection_errno) &&
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server_version != MYSQL_SERVER_VERSION_51)
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{
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/* Get Master_Server_Id */
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master_server_id = scan_server_id(row[i_master_server_id]);
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}
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if (server_version == MYSQL_SERVER_VERSION_100)
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{
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const char* beats = mxs_mysql_get_value(result, row, "Slave_received_heartbeats");
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const char* period = mxs_mysql_get_value(result, row, "Slave_heartbeat_period");
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const char* using_gtid = mxs_mysql_get_value(result, row, "Using_Gtid");
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const char* master_host = mxs_mysql_get_value(result, row, "Master_Host");
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const char* master_port = mxs_mysql_get_value(result, row, "Master_Port");
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const char* last_io_error = mxs_mysql_get_value(result, row, "Last_IO_Error");
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const char* last_sql_error = mxs_mysql_get_value(result, row, "Last_SQL_Error");
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ss_dassert(beats && period && using_gtid && master_host && master_port &&
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last_io_error && last_sql_error);
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serv_info->slave_status.master_host = master_host;
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serv_info->slave_status.master_port = atoi(master_port);
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serv_info->slave_status.last_error = *last_io_error ? last_io_error :
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(*last_sql_error ? last_sql_error : "");
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int heartbeats = atoi(beats);
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if (serv_info->slave_heartbeats < heartbeats)
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{
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serv_info->latest_event = time(NULL);
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serv_info->slave_heartbeats = heartbeats;
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serv_info->heartbeat_period = atof(period);
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}
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if (m_master_gtid_domain >= 0 &&
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(strcmp(using_gtid, "Current_Pos") == 0 || strcmp(using_gtid, "Slave_Pos") == 0))
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{
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const char* gtid_io_pos = mxs_mysql_get_value(result, row, "Gtid_IO_Pos");
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ss_dassert(gtid_io_pos);
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serv_info->slave_status.gtid_io_pos = gtid_io_pos[0] != '\0' ?
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Gtid(gtid_io_pos, m_master_gtid_domain) :
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Gtid();
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}
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|
else
|
|
{
|
|
serv_info->slave_status.gtid_io_pos = Gtid();
|
|
}
|
|
}
|
|
|
|
nconfigured++;
|
|
row = mysql_fetch_row(result);
|
|
}
|
|
while (row);
|
|
}
|
|
else
|
|
{
|
|
/** Query returned no rows, replication is not configured */
|
|
serv_info->slave_configured = false;
|
|
serv_info->slave_heartbeats = 0;
|
|
serv_info->slave_status = SlaveStatusInfo();
|
|
}
|
|
|
|
serv_info->slave_status.master_server_id = master_server_id;
|
|
mysql_free_result(result);
|
|
}
|
|
else
|
|
{
|
|
mon_report_query_error(database);
|
|
}
|
|
|
|
serv_info->n_slaves_configured = nconfigured;
|
|
serv_info->n_slaves_running = nrunning;
|
|
|
|
return rval;
|
|
}
|
|
|
|
/**
|
|
* @brief A node in a graph
|
|
*/
|
|
struct graph_node
|
|
{
|
|
int index;
|
|
int lowest_index;
|
|
int cycle;
|
|
bool active;
|
|
struct graph_node *parent;
|
|
MySqlServerInfo *info;
|
|
MXS_MONITORED_SERVER *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;
|
|
if (*stacksize > 0)
|
|
{
|
|
*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(MariaDBMonitor *handle, MXS_MONITORED_SERVER *database, int nservers)
|
|
{
|
|
struct graph_node graph[nservers];
|
|
struct graph_node *stack[nservers];
|
|
int nodes = 0;
|
|
|
|
for (MXS_MONITORED_SERVER *db = database; db; db = db->next)
|
|
{
|
|
graph[nodes].info = handle->get_server_info(db);
|
|
graph[nodes].db = db;
|
|
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->slave_status.master_server_id > 0)
|
|
{
|
|
/** Found a connected node */
|
|
for (int k = 0; k < nservers; k++)
|
|
{
|
|
if (graph[k].info->server_id == graph[i].info->slave_status.master_server_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 | SERVER_STALE_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 | SERVER_STALE_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.
|
|
*/
|
|
if (graph[i].info->read_only)
|
|
{
|
|
/** The master is in read-only mode, set it into Slave state */
|
|
monitor_set_pending_status(graph[i].db, SERVER_SLAVE | SERVER_STALE_SLAVE);
|
|
monitor_clear_pending_status(graph[i].db, SERVER_MASTER | SERVER_STALE_STATUS);
|
|
}
|
|
else
|
|
{
|
|
monitor_set_pending_status(graph[i].db, SERVER_MASTER | SERVER_STALE_STATUS);
|
|
monitor_clear_pending_status(graph[i].db, SERVER_SLAVE | SERVER_STALE_SLAVE);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Monitor an individual server.
|
|
*
|
|
* @param database The database to probe
|
|
*/
|
|
void MariaDBMonitor::monitor_database(MXS_MONITORED_SERVER *database)
|
|
{
|
|
/* Don't probe servers in maintenance mode */
|
|
if (SERVER_IN_MAINT(database->server))
|
|
{
|
|
return;
|
|
}
|
|
|
|
/** Store previous status */
|
|
database->mon_prev_status = database->server->status;
|
|
|
|
mxs_connect_result_t rval = mon_ping_or_connect_to_db(m_monitor_base, database);
|
|
if (rval == MONITOR_CONN_OK)
|
|
{
|
|
server_clear_status_nolock(database->server, SERVER_AUTH_ERROR);
|
|
monitor_clear_pending_status(database, SERVER_AUTH_ERROR);
|
|
}
|
|
else
|
|
{
|
|
/**
|
|
* The current server is not running. Clear all but the stale master bit
|
|
* as it is used to detect masters that went down but came up.
|
|
*/
|
|
unsigned int all_bits = ~SERVER_STALE_STATUS;
|
|
server_clear_status_nolock(database->server, all_bits);
|
|
monitor_clear_pending_status(database, all_bits);
|
|
|
|
if (mysql_errno(database->con) == ER_ACCESS_DENIED_ERROR)
|
|
{
|
|
server_set_status_nolock(database->server, SERVER_AUTH_ERROR);
|
|
monitor_set_pending_status(database, SERVER_AUTH_ERROR);
|
|
}
|
|
|
|
/* 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_nolock(database->server, SERVER_RUNNING);
|
|
monitor_set_pending_status(database, SERVER_RUNNING);
|
|
|
|
MySqlServerInfo *serv_info = get_server_info(database);
|
|
/* Check whether current server is MaxScale Binlog Server */
|
|
MYSQL_RES *result;
|
|
if (mxs_mysql_query(database->con, "SELECT @@maxscale_version") == 0 &&
|
|
(result = mysql_store_result(database->con)) != NULL)
|
|
{
|
|
serv_info->binlog_relay = true;
|
|
mysql_free_result(result);
|
|
}
|
|
else
|
|
{
|
|
serv_info->binlog_relay = false;
|
|
}
|
|
|
|
/* Get server version string, also get/set numeric representation. */
|
|
mxs_mysql_set_server_version(database->con, database->server);
|
|
/* Set monitor version enum. */
|
|
uint64_t version_num = server_get_version(database->server);
|
|
if (version_num >= 100000)
|
|
{
|
|
serv_info->version = MYSQL_SERVER_VERSION_100;
|
|
}
|
|
else if (version_num >= 5 * 10000 + 5 * 100)
|
|
{
|
|
serv_info->version = MYSQL_SERVER_VERSION_55;
|
|
}
|
|
else
|
|
{
|
|
serv_info->version = MYSQL_SERVER_VERSION_51;
|
|
}
|
|
/* Query a few settings. */
|
|
read_server_variables(database, serv_info);
|
|
/* If gtid domain exists and server is 10.0, update gtid:s */
|
|
if (m_master_gtid_domain >= 0 && serv_info->version == MYSQL_SERVER_VERSION_100)
|
|
{
|
|
update_gtids(database, serv_info);
|
|
}
|
|
/* Check for MariaDB 10.x.x and get status for multi-master replication */
|
|
if (serv_info->version == MYSQL_SERVER_VERSION_100 || serv_info->version == MYSQL_SERVER_VERSION_55)
|
|
{
|
|
monitor_mysql_db(database, serv_info);
|
|
}
|
|
else
|
|
{
|
|
if (m_mysql51_replication)
|
|
{
|
|
monitor_mysql_db(database, serv_info);
|
|
}
|
|
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.");
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Read server_id, read_only and (if 10.X) gtid_domain_id.
|
|
*
|
|
* @param database Database to update
|
|
* @param serv_info Where to save results
|
|
*/
|
|
static void read_server_variables(MXS_MONITORED_SERVER* database, MySqlServerInfo* serv_info)
|
|
{
|
|
string query = "SELECT @@global.server_id, @@read_only;";
|
|
int columns = 2;
|
|
if (serv_info->version == MYSQL_SERVER_VERSION_100)
|
|
{
|
|
query.erase(query.end() - 1);
|
|
query += ", @@gtid_domain_id;";
|
|
columns = 3;
|
|
}
|
|
|
|
int ind_id = 0;
|
|
int ind_ro = 1;
|
|
int ind_domain = 2;
|
|
StringVector row;
|
|
if (query_one_row(database, query.c_str(), columns, &row))
|
|
{
|
|
int64_t server_id = scan_server_id(row[ind_id].c_str());
|
|
database->server->node_id = server_id;
|
|
serv_info->server_id = server_id;
|
|
|
|
ss_dassert(row[ind_ro] == "0" || row[ind_ro] == "1");
|
|
serv_info->read_only = (row[ind_ro] == "1");
|
|
if (columns == 3)
|
|
{
|
|
uint32_t domain = 0;
|
|
ss_debug(int rv = ) sscanf(row[ind_domain].c_str(), "%" PRIu32, &domain);
|
|
ss_dassert(rv == 1);
|
|
serv_info->gtid_domain_id = domain;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Monitor a database with given server info.
|
|
*
|
|
* @param database Database to monitor
|
|
* @param serv_info Server info for database
|
|
*/
|
|
void MariaDBMonitor::monitor_mysql_db(MXS_MONITORED_SERVER* database, MySqlServerInfo *serv_info)
|
|
{
|
|
/** Clear old states */
|
|
monitor_clear_pending_status(database, SERVER_SLAVE | SERVER_MASTER | SERVER_RELAY_MASTER |
|
|
SERVER_SLAVE_OF_EXTERNAL_MASTER);
|
|
|
|
if (do_show_slave_status(serv_info, database))
|
|
{
|
|
/* If all configured slaves are running set this node as slave */
|
|
if (serv_info->slave_configured && serv_info->n_slaves_running > 0 &&
|
|
serv_info->n_slaves_running == serv_info->n_slaves_configured)
|
|
{
|
|
monitor_set_pending_status(database, SERVER_SLAVE);
|
|
}
|
|
|
|
/** Store master_id of current node. For MySQL 5.1 it will be set at a later point. */
|
|
database->server->master_id = serv_info->slave_status.master_server_id;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Query gtid_current_pos and gtid_binlog_pos and save the values to the server info object.
|
|
* Only the cluster master domain is parsed.
|
|
*
|
|
* @param mon Cluster monitor
|
|
* @param database The server to query
|
|
* @param info Server info structure for saving result TODO: remove
|
|
* @return True if successful
|
|
*/
|
|
bool MariaDBMonitor::update_gtids(MXS_MONITORED_SERVER *database, MySqlServerInfo* info)
|
|
{
|
|
StringVector row;
|
|
const char query[] = "SELECT @@gtid_current_pos, @@gtid_binlog_pos;";
|
|
const int ind_current_pos = 0;
|
|
const int ind_binlog_pos = 1;
|
|
int64_t domain = m_master_gtid_domain;
|
|
ss_dassert(domain >= 0);
|
|
bool rval = false;
|
|
if (query_one_row(database, query, 2, &row))
|
|
{
|
|
info->gtid_current_pos = (row[ind_current_pos] != "") ?
|
|
Gtid(row[ind_current_pos].c_str(), domain) : Gtid();
|
|
info->gtid_binlog_pos = (row[ind_binlog_pos] != "") ?
|
|
Gtid(row[ind_binlog_pos].c_str(), domain) : Gtid();
|
|
rval = true;
|
|
}
|
|
return rval;
|
|
}
|
|
|
|
/**
|
|
* Update replication settings and gtid:s of the slave server.
|
|
*
|
|
* @param server Slave to update
|
|
* @return Slave server info. NULL on error, or if server is not a slave.
|
|
*/
|
|
MySqlServerInfo* MariaDBMonitor::update_slave_info(MXS_MONITORED_SERVER* server)
|
|
{
|
|
MySqlServerInfo* info = get_server_info(server);
|
|
if (info->slave_status.slave_sql_running &&
|
|
update_replication_settings(server, info) &&
|
|
update_gtids(server, info) &&
|
|
do_show_slave_status(info, server))
|
|
{
|
|
return info;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* Query a few miscellaneous replication settings.
|
|
*
|
|
* @param database The slave server to query
|
|
* @param info Where to save results
|
|
* @return True on success
|
|
*/
|
|
bool MariaDBMonitor::update_replication_settings(MXS_MONITORED_SERVER *database, MySqlServerInfo* info)
|
|
{
|
|
StringVector row;
|
|
bool ok = query_one_row(database, "SELECT @@gtid_strict_mode, @@log_bin, @@log_slave_updates;", 3, &row);
|
|
if (ok)
|
|
{
|
|
info->rpl_settings.gtid_strict_mode = (row[0] == "1");
|
|
info->rpl_settings.log_bin = (row[1] == "1");
|
|
info->rpl_settings.log_slave_updates = (row[2] == "1");
|
|
}
|
|
return ok;
|
|
} |