778 lines
24 KiB
C++
778 lines
24 KiB
C++
/*
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* Copyright (c) 2016 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: 2022-01-01
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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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/**
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* @file galera_mon.c - A MySQL Galera cluster monitor
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*/
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#define MXS_MODULE_NAME "galeramon"
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#include "galeramon.hh"
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <mysql.h>
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#include <mysqld_error.h>
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#include <maxscale/alloc.h>
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#include <maxscale/config.h>
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#include <maxscale/dcb.h>
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#include <maxscale/log.h>
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#include <maxscale/modinfo.h>
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#include <maxscale/mysql_utils.h>
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#include <maxscale/secrets.h>
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#define DONOR_NODE_NAME_MAX_LEN 60
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#define DONOR_LIST_SET_VAR "SET GLOBAL wsrep_sst_donor = \""
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/** Log a warning when a bad 'wsrep_local_index' is found */
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static bool warn_erange_on_local_index = true;
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static MXS_MONITORED_SERVER* set_cluster_master(MXS_MONITORED_SERVER*, MXS_MONITORED_SERVER*, int);
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static void disableMasterFailback(void*, int);
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static int compare_node_index(const void*, const void*);
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static int compare_node_priority(const void*, const void*);
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static bool using_xtrabackup(MXS_MONITORED_SERVER* database, const char* server_string);
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GaleraMonitor::GaleraMonitor(MXS_MONITOR* mon)
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: maxscale::MonitorInstanceSimple(mon)
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, m_id(MXS_MONITOR_DEFAULT_ID)
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, m_disableMasterFailback(0)
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, m_availableWhenDonor(0)
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, m_disableMasterRoleSetting(0)
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, m_root_node_as_master(false)
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, m_use_priority(false)
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, m_set_donor_nodes(false)
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, m_log_no_members(false)
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, m_cluster_size(0)
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{
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}
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GaleraMonitor::~GaleraMonitor()
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{
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}
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// static
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GaleraMonitor* GaleraMonitor::create(MXS_MONITOR* monitor)
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{
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return new GaleraMonitor(monitor);
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}
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void GaleraMonitor::diagnostics(DCB* dcb) const
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{
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dcb_printf(dcb, "Master Failback:\t%s\n", (m_disableMasterFailback == 1) ? "off" : "on");
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dcb_printf(dcb, "Available when Donor:\t%s\n", (m_availableWhenDonor == 1) ? "on" : "off");
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dcb_printf(dcb,
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"Master Role Setting Disabled:\t%s\n",
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m_disableMasterRoleSetting ? "on" : "off");
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dcb_printf(dcb, "Set wsrep_sst_donor node list:\t%s\n", (m_set_donor_nodes == 1) ? "on" : "off");
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if (!m_cluster_uuid.empty())
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{
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dcb_printf(dcb, "Galera Cluster UUID:\t%s\n", m_cluster_uuid.c_str());
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dcb_printf(dcb, "Galera Cluster size:\t%d\n", m_cluster_size);
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}
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else
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{
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dcb_printf(dcb, "Galera Cluster NOT set:\tno member nodes\n");
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}
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}
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json_t* GaleraMonitor::diagnostics_json() const
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{
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json_t* rval = MonitorInstance::diagnostics_json();
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json_object_set_new(rval, "disable_master_failback", json_boolean(m_disableMasterFailback));
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json_object_set_new(rval, "disable_master_role_setting", json_boolean(m_disableMasterRoleSetting));
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json_object_set_new(rval, "root_node_as_master", json_boolean(m_root_node_as_master));
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json_object_set_new(rval, "use_priority", json_boolean(m_use_priority));
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json_object_set_new(rval, "set_donor_nodes", json_boolean(m_set_donor_nodes));
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if (!m_cluster_uuid.empty())
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{
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json_object_set_new(rval, "cluster_uuid", json_string(m_cluster_uuid.c_str()));
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json_object_set_new(rval, "cluster_size", json_integer(m_cluster_size));
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}
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return rval;
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}
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bool GaleraMonitor::configure(const MXS_CONFIG_PARAMETER* params)
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{
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m_disableMasterFailback = config_get_bool(params, "disable_master_failback");
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m_availableWhenDonor = config_get_bool(params, "available_when_donor");
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m_disableMasterRoleSetting = config_get_bool(params, "disable_master_role_setting");
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m_root_node_as_master = config_get_bool(params, "root_node_as_master");
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m_use_priority = config_get_bool(params, "use_priority");
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m_set_donor_nodes = config_get_bool(params, "set_donor_nodes");
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m_log_no_members = true;
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/* Reset all data in the hashtable */
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m_info.clear();
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return true;
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}
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bool GaleraMonitor::has_sufficient_permissions() const
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{
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return check_monitor_permissions(m_monitor, "SHOW STATUS LIKE 'wsrep_local_state'");
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}
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void GaleraMonitor::update_server_status(MXS_MONITORED_SERVER* monitored_server)
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{
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MYSQL_ROW row;
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MYSQL_RES* result;
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char* server_string;
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/* get server version string */
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mxs_mysql_set_server_version(monitored_server->con, monitored_server->server);
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server_string = monitored_server->server->version_string;
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/* Check if the the Galera FSM shows this node is joined to the cluster */
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const char* cluster_member =
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"SHOW STATUS WHERE Variable_name IN"
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" ('wsrep_cluster_state_uuid',"
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" 'wsrep_cluster_size',"
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" 'wsrep_local_index',"
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" 'wsrep_local_state')";
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if (mxs_mysql_query(monitored_server->con, cluster_member) == 0
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&& (result = mysql_store_result(monitored_server->con)) != NULL)
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{
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if (mysql_field_count(monitored_server->con) < 2)
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{
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mysql_free_result(result);
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MXS_ERROR("Unexpected result for \"%s\". "
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"Expected 2 columns. MySQL Version: %s",
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cluster_member,
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server_string);
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return;
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}
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GaleraNode info = {};
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while ((row = mysql_fetch_row(result)))
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{
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if (strcmp(row[0], "wsrep_cluster_size") == 0)
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{
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info.cluster_size = atoi(row[1]);
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}
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if (strcmp(row[0], "wsrep_local_index") == 0)
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{
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char* endchar;
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long local_index = strtol(row[1], &endchar, 10);
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if (*endchar != '\0'
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|| (errno == ERANGE && (local_index == LONG_MAX || local_index == LONG_MIN)))
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{
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if (warn_erange_on_local_index)
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{
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MXS_WARNING("Invalid 'wsrep_local_index' on server '%s': %s",
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monitored_server->server->name,
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row[1]);
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warn_erange_on_local_index = false;
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}
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local_index = -1;
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/* Force joined = 0 */
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info.joined = 0;
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}
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info.local_index = local_index;
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}
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mxb_assert(row[0] && row[1]);
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if (strcmp(row[0], "wsrep_local_state") == 0)
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{
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if (strcmp(row[1], "4") == 0)
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{
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info.joined = 1;
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}
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/* Check if the node is a donor and is using xtrabackup, in this case it can stay alive */
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else if (strcmp(row[1], "2") == 0 && m_availableWhenDonor == 1
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&& using_xtrabackup(monitored_server, server_string))
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{
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info.joined = 1;
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}
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else
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{
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/* Force joined = 0 */
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info.joined = 0;
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}
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info.local_state = atoi(row[1]);
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}
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/* We can check:
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* wsrep_local_state == 0
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* wsrep_cluster_size == 0
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* wsrep_cluster_state_uuid == ""
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*/
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if (strcmp(row[0], "wsrep_cluster_state_uuid") == 0)
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{
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if (row[1] == NULL || !strlen(row[1]))
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{
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info.cluster_uuid.clear();
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info.joined = 0;
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}
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else
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{
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info.cluster_uuid = MXS_STRDUP(row[1]);
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}
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}
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}
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monitored_server->server->node_id = info.joined ? info.local_index : -1;
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m_info[monitored_server] = info;
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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(monitored_server);
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}
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}
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void GaleraMonitor::pre_tick()
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{
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// Clear the info before monitoring to make sure it's up to date
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m_info.clear();
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}
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void GaleraMonitor::post_tick()
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{
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int is_cluster = 0;
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/* Try to set a Galera cluster based on
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* UUID and cluster_size each node reports:
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* no multiple clusters UUID are allowed.
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*/
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set_galera_cluster();
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/*
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* Let's select a master server:
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* it could be the candidate master following MXS_MIN(node_id) rule or
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* the server that was master in the previous monitor polling cycle
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* Decision depends on master_stickiness value set in configuration
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*/
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/* get the candidate master, following MXS_MIN(node_id) rule */
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MXS_MONITORED_SERVER* candidate_master = get_candidate_master();
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m_master = set_cluster_master(m_master, candidate_master, m_disableMasterFailback);
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MXS_MONITORED_SERVER* ptr = m_monitor->monitored_servers;
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while (ptr)
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{
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const int repl_bits = (SERVER_SLAVE | SERVER_MASTER | SERVER_MASTER_STICKINESS);
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if ((ptr->pending_status & SERVER_JOINED) && !m_disableMasterRoleSetting)
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{
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if (ptr != m_master)
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{
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/* set the Slave role and clear master stickiness */
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monitor_clear_pending_status(ptr, repl_bits);
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monitor_set_pending_status(ptr, SERVER_SLAVE);
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}
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else
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{
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if (candidate_master
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&& m_master->server->node_id != candidate_master->server->node_id)
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{
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/* set master role and master stickiness */
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monitor_clear_pending_status(ptr, repl_bits);
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monitor_set_pending_status(ptr, SERVER_MASTER | SERVER_MASTER_STICKINESS);
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}
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else
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{
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/* set master role and clear master stickiness */
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monitor_clear_pending_status(ptr, repl_bits);
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monitor_set_pending_status(ptr, SERVER_MASTER);
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}
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}
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is_cluster++;
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}
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else
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{
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monitor_clear_pending_status(ptr, repl_bits);
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monitor_set_pending_status(ptr, 0);
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}
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ptr = ptr->next;
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}
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if (is_cluster == 0 && m_log_no_members)
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{
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MXS_ERROR("There are no cluster members");
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m_log_no_members = false;
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}
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else
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{
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if (is_cluster > 0 && m_log_no_members == 0)
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{
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MXS_NOTICE("Found cluster members");
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m_log_no_members = true;
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}
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}
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/* Set the global var "wsrep_sst_donor"
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* with a sorted list of "wsrep_node_name" for slave nodes
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*/
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if (m_set_donor_nodes)
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{
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update_sst_donor_nodes(is_cluster);
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}
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}
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static bool using_xtrabackup(MXS_MONITORED_SERVER* database, const char* server_string)
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{
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bool rval = false;
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MYSQL_RES* result;
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if (mxs_mysql_query(database->con, "SHOW VARIABLES LIKE 'wsrep_sst_method'") == 0
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&& (result = mysql_store_result(database->con)) != NULL)
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{
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if (mysql_field_count(database->con) < 2)
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{
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mysql_free_result(result);
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MXS_ERROR("Unexpected result for \"SHOW VARIABLES LIKE "
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"'wsrep_sst_method'\". Expected 2 columns."
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" MySQL Version: %s",
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server_string);
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}
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MYSQL_ROW row;
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while ((row = mysql_fetch_row(result)))
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{
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if (row[1] && (strcmp(row[1], "xtrabackup") == 0 || strcmp(row[1], "mariabackup") == 0))
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{
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rval = true;
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}
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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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return rval;
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}
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/**
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* get candidate master from all nodes
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*
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* The current available rule: get the server with MXS_MIN(node_id)
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* node_id comes from 'wsrep_local_index' variable
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*
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* @param servers The monitored servers list
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* @return The candidate master on success, NULL on failure
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*/
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MXS_MONITORED_SERVER* GaleraMonitor::get_candidate_master()
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{
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MXS_MONITORED_SERVER* moitor_servers = m_monitor->monitored_servers;
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MXS_MONITORED_SERVER* candidate_master = NULL;
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long min_id = -1;
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int minval = INT_MAX;
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int currval;
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/* set min_id to the lowest value of moitor_servers->server->node_id */
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while (moitor_servers)
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{
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if (!server_is_in_maint(moitor_servers->server)
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&& (moitor_servers->pending_status & SERVER_JOINED))
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{
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char buf[50]; // Enough to hold most numbers
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if (m_use_priority && server_get_parameter(moitor_servers->server, "priority", buf, sizeof(buf)))
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{
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/** The server has a priority */
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if ((currval = atoi(buf)) > 0)
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{
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/** The priority is valid */
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if (currval < minval && currval > 0)
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{
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minval = currval;
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candidate_master = moitor_servers;
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}
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}
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}
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else if (moitor_servers->server->node_id >= 0
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&& (!m_use_priority || candidate_master == NULL))
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{
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// Server priorities are not in use or no candidate has been found
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if (min_id < 0 || moitor_servers->server->node_id < min_id)
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{
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min_id = moitor_servers->server->node_id;
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candidate_master = moitor_servers;
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}
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}
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}
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moitor_servers = moitor_servers->next;
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}
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if (!m_use_priority && !m_disableMasterFailback
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&& m_root_node_as_master && min_id > 0)
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{
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/** The monitor couldn't find the node with wsrep_local_index of 0.
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* This means that we can't connect to the root node of the cluster.
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*
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* If the node is down, the cluster would recalculate the index values
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* and we would find it. In this case, we just can't connect to it.
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*/
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candidate_master = NULL;
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}
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return candidate_master;
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}
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/**
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* set the master server in the cluster
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*
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* master could be the last one from previous monitor cycle Iis running) or
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* the candidate master.
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* The selection is based on the configuration option mapped to master_stickiness
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* The candidate master may change over time due to
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* 'wsrep_local_index' value change in the Galera Cluster
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* Enabling master_stickiness will avoid master change unless a failure is spotted
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*
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* @param current_master Previous master server
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* @param candidate_master The candidate master server accordingly to the selection rule
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* @return The master node pointer (could be NULL)
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*/
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static MXS_MONITORED_SERVER* set_cluster_master(MXS_MONITORED_SERVER* current_master,
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MXS_MONITORED_SERVER* candidate_master,
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int master_stickiness)
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{
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/*
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* if current master is not set or master_stickiness is not enable
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* just return candidate_master.
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*/
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if (current_master == NULL || master_stickiness == 0)
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{
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return candidate_master;
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}
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else
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{
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/*
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* if current_master is still a cluster member use it
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*
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*/
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if ((current_master->pending_status & SERVER_JOINED)
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&& (!server_is_in_maint(current_master->server)))
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{
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return current_master;
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}
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else
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{
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return candidate_master;
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}
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}
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}
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/**
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* Set the global variable wsrep_sst_donor in the cluster
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*
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* The monitor user must have the privileges for setting global vars.
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*
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* Galera monitor fetches from each joined slave node the var 'wsrep_node_name'
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* A list of nodes is automatically build and it's sorted by wsrep_local_index DESC
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* or by priority ASC if use_priority option is set.
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*
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* The list is then added to SET GLOBAL VARIABLE wrep_sst_donor =
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* The variable must be sent to all slave nodes.
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*
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* All slave nodes have a sorted list of nodes tht can be used as donor nodes.
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*
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* If there is only one node the funcion returns,
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*
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* @param mon The monitor handler
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* @param is_cluster The number of joined nodes
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*/
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void GaleraMonitor::update_sst_donor_nodes(int is_cluster)
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{
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MXS_MONITORED_SERVER* ptr;
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MYSQL_ROW row;
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MYSQL_RES* result;
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bool ignore_priority = true;
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if (is_cluster == 1)
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{
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return; // Only one server in the cluster: update_sst_donor_nodes is not performed
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|
}
|
|
|
|
unsigned int found_slaves = 0;
|
|
MXS_MONITORED_SERVER* node_list[is_cluster - 1];
|
|
/* Donor list size = DONOR_LIST_SET_VAR + n_hosts * max_host_len + n_hosts + 1 */
|
|
|
|
char* donor_list = static_cast<char*>(MXS_CALLOC(1,
|
|
strlen(DONOR_LIST_SET_VAR)
|
|
+ is_cluster * DONOR_NODE_NAME_MAX_LEN
|
|
+ is_cluster + 1));
|
|
|
|
if (donor_list == NULL)
|
|
{
|
|
MXS_ERROR("can't execute update_sst_donor_nodes() due to memory allocation error");
|
|
return;
|
|
}
|
|
|
|
strcpy(donor_list, DONOR_LIST_SET_VAR);
|
|
|
|
ptr = m_monitor->monitored_servers;
|
|
|
|
/* Create an array of slave nodes */
|
|
while (ptr)
|
|
{
|
|
if ((ptr->pending_status & SERVER_JOINED) && (ptr->pending_status & SERVER_SLAVE))
|
|
{
|
|
node_list[found_slaves] = (MXS_MONITORED_SERVER*)ptr;
|
|
found_slaves++;
|
|
|
|
/* Check the server parameter "priority"
|
|
* If no server has "priority" set, then
|
|
* the server list will be order by default method.
|
|
*/
|
|
|
|
if (m_use_priority && server_get_parameter(ptr->server, "priority", NULL, 0))
|
|
{
|
|
ignore_priority = false;
|
|
}
|
|
}
|
|
ptr = ptr->next;
|
|
}
|
|
|
|
/* Set order type */
|
|
bool sort_order = (!ignore_priority) && (int)m_use_priority;
|
|
|
|
/* Sort the array */
|
|
qsort(node_list,
|
|
found_slaves,
|
|
sizeof(MXS_MONITORED_SERVER*),
|
|
sort_order ? compare_node_priority : compare_node_index);
|
|
|
|
/* Select nodename from each server and append it to node_list */
|
|
for (unsigned int k = 0; k < found_slaves; k++)
|
|
{
|
|
MXS_MONITORED_SERVER* ptr = node_list[k];
|
|
|
|
/* Get the Galera node name */
|
|
if (mxs_mysql_query(ptr->con, "SHOW VARIABLES LIKE 'wsrep_node_name'") == 0
|
|
&& (result = mysql_store_result(ptr->con)) != NULL)
|
|
{
|
|
if (mysql_field_count(ptr->con) < 2)
|
|
{
|
|
mysql_free_result(result);
|
|
MXS_ERROR("Unexpected result for \"SHOW VARIABLES LIKE 'wsrep_node_name'\". "
|
|
"Expected 2 columns");
|
|
return;
|
|
}
|
|
|
|
while ((row = mysql_fetch_row(result)))
|
|
{
|
|
strncat(donor_list, row[1], DONOR_NODE_NAME_MAX_LEN);
|
|
strcat(donor_list, ",");
|
|
}
|
|
|
|
mysql_free_result(result);
|
|
}
|
|
else
|
|
{
|
|
mon_report_query_error(ptr);
|
|
}
|
|
}
|
|
|
|
int donor_list_size = strlen(donor_list);
|
|
if (donor_list[donor_list_size - 1] == ',')
|
|
{
|
|
donor_list[donor_list_size - 1] = '\0';
|
|
}
|
|
|
|
strcat(donor_list, "\"");
|
|
|
|
/* Set now rep_sst_donor in each slave node */
|
|
for (unsigned int k = 0; k < found_slaves; k++)
|
|
{
|
|
MXS_MONITORED_SERVER* ptr = node_list[k];
|
|
if (mxs_mysql_query(ptr->con, donor_list) != 0)
|
|
{
|
|
mon_report_query_error(ptr);
|
|
}
|
|
}
|
|
|
|
MXS_FREE(donor_list);
|
|
}
|
|
|
|
/**
|
|
* Compare routine for slave nodes sorted by 'wsrep_local_index'
|
|
*
|
|
* The default order is DESC.
|
|
*
|
|
* Nodes with lowest 'wsrep_local_index' value
|
|
* are at the end of the list.
|
|
*
|
|
* @param a Pointer to array value
|
|
* @param b Pointer to array value
|
|
* @return A number less than, threater than or equal to 0
|
|
*/
|
|
|
|
static int compare_node_index(const void* a, const void* b)
|
|
{
|
|
const MXS_MONITORED_SERVER* s_a = *(MXS_MONITORED_SERVER* const*)a;
|
|
const MXS_MONITORED_SERVER* s_b = *(MXS_MONITORED_SERVER* const*)b;
|
|
|
|
// Order is DESC: b - a
|
|
return s_b->server->node_id - s_a->server->node_id;
|
|
}
|
|
|
|
/**
|
|
* Compare routine for slave nodes sorted by node priority
|
|
*
|
|
* The default order is DESC.
|
|
*
|
|
* Some special cases, i.e: no give priority, or 0 value
|
|
* are handled.
|
|
*
|
|
* Note: the master selection algorithm is:
|
|
* node with lowest priority value and > 0
|
|
*
|
|
* This sorting function will add master candidates
|
|
* at the end of the list.
|
|
*
|
|
* @param a Pointer to array value
|
|
* @param b Pointer to array value
|
|
* @return A number less than, threater than or equal to 0
|
|
*/
|
|
|
|
static int compare_node_priority(const void* a, const void* b)
|
|
{
|
|
const MXS_MONITORED_SERVER* s_a = *(MXS_MONITORED_SERVER* const*)a;
|
|
const MXS_MONITORED_SERVER* s_b = *(MXS_MONITORED_SERVER* const*)b;
|
|
char pri_a[50];
|
|
char pri_b[50];
|
|
bool have_a = server_get_parameter(s_a->server, "priority", pri_a, sizeof(pri_a));
|
|
bool have_b = server_get_parameter(s_b->server, "priority", pri_b, sizeof(pri_b));
|
|
|
|
/**
|
|
* Check priority parameter:
|
|
*
|
|
* Return a - b in case of issues
|
|
*/
|
|
if (!have_a && have_b)
|
|
{
|
|
MXS_DEBUG("Server %s has no given priority. It will be at the beginning of the list",
|
|
s_a->server->name);
|
|
return -(INT_MAX - 1);
|
|
}
|
|
else if (have_a && !have_b)
|
|
{
|
|
MXS_DEBUG("Server %s has no given priority. It will be at the beginning of the list",
|
|
s_b->server->name);
|
|
return INT_MAX - 1;
|
|
}
|
|
else if (!have_a && !have_b)
|
|
{
|
|
MXS_DEBUG("Servers %s and %s have no given priority. They be at the beginning of the list",
|
|
s_a->server->name,
|
|
s_b->server->name);
|
|
return 0;
|
|
}
|
|
|
|
/* The given priority is valid */
|
|
int pri_val_a = atoi(pri_a);
|
|
int pri_val_b = atoi(pri_b);
|
|
|
|
/* Return a - b in case of issues */
|
|
if ((pri_val_a < INT_MAX && pri_val_a > 0) && !(pri_val_b < INT_MAX && pri_val_b > 0))
|
|
{
|
|
return pri_val_a;
|
|
}
|
|
else if (!(pri_val_a < INT_MAX && pri_val_a > 0) && (pri_val_b < INT_MAX && pri_val_b > 0))
|
|
{
|
|
return -pri_val_b;
|
|
}
|
|
else if (!(pri_val_a < INT_MAX && pri_val_a > 0) && !(pri_val_b < INT_MAX && pri_val_b > 0))
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
// The order is DESC: b -a
|
|
return pri_val_b - pri_val_a;
|
|
}
|
|
|
|
/**
|
|
* Only set the servers as joined if they are a part of the largest cluster
|
|
*/
|
|
void GaleraMonitor::set_galera_cluster()
|
|
{
|
|
int cluster_size = 0;
|
|
std::string cluster_uuid;
|
|
|
|
for (auto it = m_info.begin(); it != m_info.end(); it++)
|
|
{
|
|
if (it->second.joined && it->second.cluster_size > cluster_size)
|
|
{
|
|
// Use the UUID of the largest cluster
|
|
cluster_size = it->second.cluster_size;
|
|
cluster_uuid = it->second.cluster_uuid;
|
|
}
|
|
}
|
|
|
|
for (auto it = m_info.begin(); it != m_info.end(); it++)
|
|
{
|
|
if (it->second.joined)
|
|
{
|
|
monitor_set_pending_status(it->first, SERVER_JOINED);
|
|
}
|
|
else
|
|
{
|
|
monitor_clear_pending_status(it->first, SERVER_JOINED);
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
*/
|
|
extern "C" MXS_MODULE* MXS_CREATE_MODULE()
|
|
{
|
|
MXS_NOTICE("Initialise the MySQL Galera Monitor module.");
|
|
|
|
static MXS_MODULE info =
|
|
{
|
|
MXS_MODULE_API_MONITOR,
|
|
MXS_MODULE_GA,
|
|
MXS_MONITOR_VERSION,
|
|
"A Galera cluster monitor",
|
|
"V2.0.0",
|
|
MXS_NO_MODULE_CAPABILITIES,
|
|
&maxscale::MonitorApi<GaleraMonitor>::s_api,
|
|
NULL, /* Process init. */
|
|
NULL, /* Process finish. */
|
|
NULL, /* Thread init. */
|
|
NULL, /* Thread finish. */
|
|
{
|
|
{"disable_master_failback", MXS_MODULE_PARAM_BOOL, "false"},
|
|
{"available_when_donor", MXS_MODULE_PARAM_BOOL, "false"},
|
|
{"disable_master_role_setting", MXS_MODULE_PARAM_BOOL, "false"},
|
|
{"root_node_as_master", MXS_MODULE_PARAM_BOOL, "false"},
|
|
{"use_priority", MXS_MODULE_PARAM_BOOL, "false"},
|
|
{"set_donor_nodes", MXS_MODULE_PARAM_BOOL, "false"},
|
|
{MXS_END_MODULE_PARAMS}
|
|
}
|
|
};
|
|
|
|
return &info;
|
|
}
|