Ejemplo n.º 1
0
func main() {
	dbconfigs.RegisterFlags()
	mysqlctl.RegisterFlags()
	flag.Parse()
	if len(flag.Args()) > 0 {
		flag.Usage()
		log.Fatalf("vttablet doesn't take any positional arguments")
	}

	servenv.Init()

	if *tabletPath == "" {
		log.Fatalf("tabletPath required")
	}
	tabletAlias := tabletParamToTabletAlias(*tabletPath)

	mycnf, err := mysqlctl.NewMycnfFromFlags(tabletAlias.Uid)
	if err != nil {
		log.Fatalf("mycnf read failed: %v", err)
	}

	dbcfgs, err := dbconfigs.Init(mycnf.SocketFile)
	if err != nil {
		log.Warning(err)
	}
	dbcfgs.App.EnableRowcache = *enableRowcache

	if *tableAclConfig != "" {
		tableacl.Init(*tableAclConfig)
	}
	tabletserver.InitQueryService()
	binlog.RegisterUpdateStreamService(mycnf)

	// Depends on both query and updateStream.
	agent, err = tabletmanager.NewActionAgent(tabletAlias, dbcfgs, mycnf, *servenv.Port, *servenv.SecurePort, *overridesFile)
	if err != nil {
		log.Fatal(err)
	}

	tabletmanager.HttpHandleSnapshots(mycnf, tabletAlias.Uid)
	servenv.OnTerm(func() {
		tabletserver.DisallowQueries()
		binlog.DisableUpdateStreamService()
		agent.Stop()
	})
	servenv.OnClose(func() {
		// We will still use the topo server during lameduck period
		// to update our state, so closing it in OnClose()
		topo.CloseServers()
	})
	servenv.RunDefault()
}
Ejemplo n.º 2
0
// InitAgent initializes the agent within vttablet.
func InitAgent(
	tabletAlias topo.TabletAlias,
	dbcfgs dbconfigs.DBConfigs,
	mycnf *mysqlctl.Mycnf,
	dbConfigsFile, dbCredentialsFile string,
	port, securePort int,
	mycnfFile, overridesFile string) (err error) {
	schemaOverrides := loadSchemaOverrides(overridesFile)

	topoServer := topo.GetServer()

	// Start the binlog server service, disabled at start.
	binlogServer = mysqlctl.NewBinlogServer(mycnf)
	mysqlctl.RegisterBinlogServerService(binlogServer)

	// Start the binlog player services, not playing at start.
	binlogPlayerMap = NewBinlogPlayerMap(topoServer, &dbcfgs.Dba)
	RegisterBinlogPlayerMap(binlogPlayerMap)

	// Compute the bind addresses
	bindAddr := fmt.Sprintf(":%v", port)
	secureAddr := ""
	if securePort != 0 {
		secureAddr = fmt.Sprintf(":%v", securePort)
	}

	exportedType := expvar.NewString("tablet-type")

	// Action agent listens to changes in zookeeper and makes
	// modifications to this tablet.
	agent, err = tm.NewActionAgent(topoServer, tabletAlias, mycnfFile, dbConfigsFile, dbCredentialsFile)
	if err != nil {
		return err
	}
	agent.AddChangeCallback(func(oldTablet, newTablet topo.Tablet) {
		if newTablet.IsServingType() {
			if dbcfgs.App.Dbname == "" {
				dbcfgs.App.Dbname = newTablet.DbName()
			}
			dbcfgs.App.KeyRange = newTablet.KeyRange
			dbcfgs.App.Keyspace = newTablet.Keyspace
			dbcfgs.App.Shard = newTablet.Shard
			// Transitioning from replica to master, first disconnect
			// existing connections. "false" indicateds that clients must
			// re-resolve their endpoint before reconnecting.
			if newTablet.Type == topo.TYPE_MASTER && oldTablet.Type != topo.TYPE_MASTER {
				ts.DisallowQueries(false)
			}
			qrs := ts.LoadCustomRules()
			if dbcfgs.App.KeyRange.IsPartial() {
				qr := ts.NewQueryRule("enforce keyspace_id range", "keyspace_id_not_in_range", ts.QR_FAIL_QUERY)
				qr.AddPlanCond(sqlparser.PLAN_INSERT_PK)
				err = qr.AddBindVarCond("keyspace_id", true, true, ts.QR_NOTIN, dbcfgs.App.KeyRange)
				if err != nil {
					log.Warningf("Unable to add keyspace rule: %v", err)
				} else {
					qrs.Add(qr)
				}
			}
			ts.AllowQueries(dbcfgs.App, schemaOverrides, qrs)
			mysqlctl.EnableUpdateStreamService(string(newTablet.Type), dbcfgs)
			if newTablet.Type != topo.TYPE_MASTER {
				ts.StartRowCacheInvalidation()
			}
		} else {
			ts.DisallowQueries(false)
			ts.StopRowCacheInvalidation()
			mysqlctl.DisableUpdateStreamService()
		}

		exportedType.Set(string(newTablet.Type))

		// BinlogServer is only enabled for replicas
		if newTablet.Type == topo.TYPE_REPLICA {
			if !mysqlctl.IsBinlogServerEnabled(binlogServer) {
				mysqlctl.EnableBinlogServerService(binlogServer, dbcfgs.App.Dbname)
			}
		} else {
			if mysqlctl.IsBinlogServerEnabled(binlogServer) {
				mysqlctl.DisableBinlogServerService(binlogServer)
			}
		}

		// See if we need to start or stop any binlog player
		if newTablet.Type == topo.TYPE_MASTER {
			binlogPlayerMap.RefreshMap(newTablet)
		} else {
			binlogPlayerMap.StopAllPlayers()
		}
	})

	mysqld := mysqlctl.NewMysqld(mycnf, dbcfgs.Dba, dbcfgs.Repl)
	if err := agent.Start(bindAddr, secureAddr, mysqld.Addr()); err != nil {
		return err
	}

	// register the RPC services from the agent
	agent.RegisterQueryService(mysqld)

	return nil
}
Ejemplo n.º 3
0
func main() {
	defer exit.Recover()

	flags := dbconfigs.AppConfig | dbconfigs.DbaConfig |
		dbconfigs.FilteredConfig | dbconfigs.ReplConfig
	dbconfigs.RegisterFlags(flags)
	mysqlctl.RegisterFlags()
	flag.Parse()
	tabletserver.Init()
	if len(flag.Args()) > 0 {
		flag.Usage()
		log.Errorf("vttablet doesn't take any positional arguments")
		exit.Return(1)
	}

	servenv.Init()

	if *tabletPath == "" {
		log.Errorf("tabletPath required")
		exit.Return(1)
	}
	tabletAlias, err := topoproto.ParseTabletAlias(*tabletPath)
	if err != nil {
		log.Error(err)
		exit.Return(1)
	}

	mycnf, err := mysqlctl.NewMycnfFromFlags(tabletAlias.Uid)
	if err != nil {
		log.Errorf("mycnf read failed: %v", err)
		exit.Return(1)
	}

	dbcfgs, err := dbconfigs.Init(mycnf.SocketFile, flags)
	if err != nil {
		log.Warning(err)
	}
	dbcfgs.App.EnableRowcache = *enableRowcache

	// creates and registers the query service
	qsc := tabletserver.NewServer()
	qsc.Register()
	binlog.RegisterUpdateStreamService(mycnf)

	if *tableAclConfig != "" {
		tableacl.Register("simpleacl", &simpleacl.Factory{})
		tableacl.Init(
			*tableAclConfig,
			func() {
				qsc.ClearQueryPlanCache()
			},
		)
	} else if *enforceTableACLConfig {
		log.Error("table acl config has to be specified with table-acl-config flag because enforce-tableacl-config is set.")
		exit.Return(1)
	}

	// Create mysqld and register the health reporter (needs to be done
	// before initializing the agent, so the initial health check
	// done by the agent has the right reporter)
	mysqld := mysqlctl.NewMysqld("Dba", "App", mycnf, &dbcfgs.Dba, &dbcfgs.App.ConnParams, &dbcfgs.Repl)
	registerHealthReporter(mysqld)

	// Depends on both query and updateStream.
	gRPCPort := int32(0)
	if servenv.GRPCPort != nil {
		gRPCPort = int32(*servenv.GRPCPort)
	}
	agent, err = tabletmanager.NewActionAgent(context.Background(), mysqld, qsc, tabletAlias, dbcfgs, mycnf, int32(*servenv.Port), gRPCPort, *overridesFile, *lockTimeout)
	if err != nil {
		log.Error(err)
		exit.Return(1)
	}

	servenv.OnRun(func() {
		addStatusParts(qsc)
	})
	servenv.OnTerm(func() {
		qsc.StopService()
		binlog.DisableUpdateStreamService()
		agent.Stop()
	})
	servenv.OnClose(func() {
		// We will still use the topo server during lameduck period
		// to update our state, so closing it in OnClose()
		topo.CloseServers()
	})
	servenv.RunDefault()
}
Ejemplo n.º 4
0
// InitAgent initializes the agent within vttablet.
func InitAgent(
	tabletAlias topo.TabletAlias,
	dbcfgs *dbconfigs.DBConfigs,
	mycnf *mysqlctl.Mycnf,
	port, securePort int,
	overridesFile string,
) (agent *tabletmanager.ActionAgent, err error) {
	schemaOverrides := loadSchemaOverrides(overridesFile)

	topoServer := topo.GetServer()
	mysqld := mysqlctl.NewMysqld(mycnf, &dbcfgs.Dba, &dbcfgs.Repl)

	statsType := stats.NewString("TabletType")
	statsKeyspace := stats.NewString("TabletKeyspace")
	statsShard := stats.NewString("TabletShard")
	statsKeyRangeStart := stats.NewString("TabletKeyRangeStart")
	statsKeyRangeEnd := stats.NewString("TabletKeyRangeEnd")

	agent, err = tabletmanager.NewActionAgent(topoServer, tabletAlias, mysqld)
	if err != nil {
		return nil, err
	}

	// Start the binlog player services, not playing at start.
	agent.BinlogPlayerMap = tabletmanager.NewBinlogPlayerMap(topoServer, &dbcfgs.App.ConnectionParams, mysqld)
	tabletmanager.RegisterBinlogPlayerMap(agent.BinlogPlayerMap)

	// Action agent listens to changes in zookeeper and makes
	// modifications to this tablet.
	agent.AddChangeCallback(func(oldTablet, newTablet topo.Tablet) {
		allowQuery := true
		var shardInfo *topo.ShardInfo
		var keyspaceInfo *topo.KeyspaceInfo
		if newTablet.Type == topo.TYPE_MASTER {
			// read the shard to get SourceShards
			shardInfo, err = topoServer.GetShard(newTablet.Keyspace, newTablet.Shard)
			if err != nil {
				log.Errorf("Cannot read shard for this tablet %v: %v", newTablet.Alias, err)
			} else {
				allowQuery = len(shardInfo.SourceShards) == 0
			}

			// read the keyspace to get ShardingColumnType
			keyspaceInfo, err = topoServer.GetKeyspace(newTablet.Keyspace)
			switch err {
			case nil:
				// continue
			case topo.ErrNoNode:
				// backward compatible mode
				keyspaceInfo = topo.NewKeyspaceInfo(newTablet.Keyspace, &topo.Keyspace{})
			default:
				log.Errorf("Cannot read keyspace for this tablet %v: %v", newTablet.Alias, err)
				keyspaceInfo = nil
			}
		}

		if newTablet.IsRunningQueryService() && allowQuery {
			if dbcfgs.App.DbName == "" {
				dbcfgs.App.DbName = newTablet.DbName()
			}
			dbcfgs.App.Keyspace = newTablet.Keyspace
			dbcfgs.App.Shard = newTablet.Shard
			if newTablet.Type != topo.TYPE_MASTER {
				dbcfgs.App.EnableInvalidator = true
			} else {
				dbcfgs.App.EnableInvalidator = false
			}
			// Transitioning from replica to master, first disconnect
			// existing connections. "false" indicateds that clients must
			// re-resolve their endpoint before reconnecting.
			if newTablet.Type == topo.TYPE_MASTER && oldTablet.Type != topo.TYPE_MASTER {
				ts.DisallowQueries()
			}
			qrs := ts.LoadCustomRules()
			if newTablet.KeyRange.IsPartial() {
				qr := ts.NewQueryRule("enforce keyspace_id range", "keyspace_id_not_in_range", ts.QR_FAIL_QUERY)
				qr.AddPlanCond(sqlparser.PLAN_INSERT_PK)
				err = qr.AddBindVarCond("keyspace_id", true, true, ts.QR_NOTIN, newTablet.KeyRange)
				if err != nil {
					log.Warningf("Unable to add keyspace rule: %v", err)
				} else {
					qrs.Add(qr)
				}
			}
			ts.AllowQueries(&dbcfgs.App, schemaOverrides, qrs, mysqld)
			// Disable before enabling to force existing streams to stop.
			binlog.DisableUpdateStreamService()
			binlog.EnableUpdateStreamService(dbcfgs)
		} else {
			ts.DisallowQueries()
			binlog.DisableUpdateStreamService()
		}

		statsType.Set(string(newTablet.Type))
		statsKeyspace.Set(newTablet.Keyspace)
		statsShard.Set(newTablet.Shard)
		statsKeyRangeStart.Set(string(newTablet.KeyRange.Start.Hex()))
		statsKeyRangeEnd.Set(string(newTablet.KeyRange.End.Hex()))

		// See if we need to start or stop any binlog player
		if newTablet.Type == topo.TYPE_MASTER {
			agent.BinlogPlayerMap.RefreshMap(newTablet, keyspaceInfo, shardInfo)
		} else {
			agent.BinlogPlayerMap.StopAllPlayersAndReset()
		}
	})

	if err := agent.Start(mysqld.Port(), port, securePort); err != nil {
		return nil, err
	}

	// register the RPC services from the agent
	agent.RegisterQueryService()

	return agent, nil
}
Ejemplo n.º 5
0
func main() {
	defer exit.Recover()

	flags := dbconfigs.AppConfig | dbconfigs.AllPrivsConfig | dbconfigs.DbaConfig |
		dbconfigs.FilteredConfig | dbconfigs.ReplConfig
	dbconfigs.RegisterFlags(flags)
	mysqlctl.RegisterFlags()
	flag.Parse()
	tabletserver.Init()
	if len(flag.Args()) > 0 {
		flag.Usage()
		log.Errorf("vttablet doesn't take any positional arguments")
		exit.Return(1)
	}

	servenv.Init()

	if *tabletPath == "" {
		log.Errorf("tabletPath required")
		exit.Return(1)
	}
	tabletAlias, err := topoproto.ParseTabletAlias(*tabletPath)
	if err != nil {
		log.Error(err)
		exit.Return(1)
	}

	mycnf, err := mysqlctl.NewMycnfFromFlags(tabletAlias.Uid)
	if err != nil {
		log.Errorf("mycnf read failed: %v", err)
		exit.Return(1)
	}

	dbcfgs, err := dbconfigs.Init(mycnf.SocketFile, flags)
	if err != nil {
		log.Warning(err)
	}

	// creates and registers the query service
	qsc := tabletserver.NewServer()
	servenv.OnRun(func() {
		qsc.Register()
		addStatusParts(qsc)
	})
	servenv.OnClose(func() {
		// We now leave the queryservice running during lameduck,
		// so stop it in OnClose(), after lameduck is over.
		qsc.StopService()
	})

	if *tableAclConfig != "" {
		// To override default simpleacl, other ACL plugins must set themselves to be default ACL factory
		tableacl.Register("simpleacl", &simpleacl.Factory{})
	} else if *enforceTableACLConfig {
		log.Error("table acl config has to be specified with table-acl-config flag because enforce-tableacl-config is set.")
		exit.Return(1)
	}
	// tabletacl.Init loads ACL from file if *tableAclConfig is not empty
	err = tableacl.Init(
		*tableAclConfig,
		func() {
			qsc.ClearQueryPlanCache()
		},
	)
	if err != nil {
		log.Errorf("Fail to initialize Table ACL: %v", err)
		if *enforceTableACLConfig {
			log.Error("Need a valid initial Table ACL when enforce-tableacl-config is set, exiting.")
			exit.Return(1)
		}
	}

	// Create mysqld and register the health reporter (needs to be done
	// before initializing the agent, so the initial health check
	// done by the agent has the right reporter)
	mysqld := mysqlctl.NewMysqld(mycnf, &dbcfgs.Dba, &dbcfgs.AllPrivs, &dbcfgs.App, &dbcfgs.Repl, true /* enablePublishStats */)
	servenv.OnClose(mysqld.Close)

	// Depends on both query and updateStream.
	gRPCPort := int32(0)
	if servenv.GRPCPort != nil {
		gRPCPort = int32(*servenv.GRPCPort)
	}
	agent, err = tabletmanager.NewActionAgent(context.Background(), mysqld, qsc, tabletAlias, dbcfgs, mycnf, int32(*servenv.Port), gRPCPort)
	if err != nil {
		log.Error(err)
		exit.Return(1)
	}

	servenv.OnClose(func() {
		// We will still use the topo server during lameduck period
		// to update our state, so closing it in OnClose()
		topo.CloseServers()
	})
	servenv.RunDefault()
}
Ejemplo n.º 6
0
func initAgent(tabletAlias topo.TabletAlias, dbcfgs dbconfigs.DBConfigs, mycnf *mysqlctl.Mycnf, dbConfigsFile, dbCredentialsFile string) error {
	topoServer := topo.GetServer()
	umgmt.AddCloseCallback(func() {
		topo.CloseServers()
	})

	bindAddr := fmt.Sprintf(":%v", *port)
	secureAddr := ""
	if *securePort != 0 {
		secureAddr = fmt.Sprintf(":%v", *securePort)
	}

	// Action agent listens to changes in zookeeper and makes
	// modifications to this tablet.
	agent, err := tm.NewActionAgent(topoServer, tabletAlias, *mycnfFile, dbConfigsFile, dbCredentialsFile)
	if err != nil {
		return err
	}
	agent.AddChangeCallback(func(oldTablet, newTablet topo.Tablet) {
		if newTablet.IsServingType() {
			if dbcfgs.App.Dbname == "" {
				dbcfgs.App.Dbname = newTablet.DbName()
			}
			dbcfgs.App.KeyRange = newTablet.KeyRange
			dbcfgs.App.Keyspace = newTablet.Keyspace
			dbcfgs.App.Shard = newTablet.Shard
			// Transitioning from replica to master, first disconnect
			// existing connections. "false" indicateds that clients must
			// re-resolve their endpoint before reconnecting.
			if newTablet.Type == topo.TYPE_MASTER && oldTablet.Type != topo.TYPE_MASTER {
				ts.DisallowQueries(false)
			}
			qrs := loadCustomRules()
			if dbcfgs.App.KeyRange.IsPartial() {
				qr := ts.NewQueryRule("enforce keyspace_id range", "keyspace_id_not_in_range", ts.QR_FAIL_QUERY)
				qr.AddPlanCond(sqlparser.PLAN_INSERT_PK)
				err = qr.AddBindVarCond("keyspace_id", true, true, ts.QR_NOTIN, dbcfgs.App.KeyRange)
				if err != nil {
					relog.Warning("Unable to add keyspace rule: %v", err)
				} else {
					qrs.Add(qr)
				}
			}
			ts.AllowQueries(dbcfgs.App, schemaOverrides, qrs)
			mysqlctl.EnableUpdateStreamService(string(newTablet.Type), dbcfgs)
			if newTablet.Type != topo.TYPE_MASTER {
				ts.StartRowCacheInvalidation()
			}
		} else {
			ts.DisallowQueries(false)
			mysqlctl.DisableUpdateStreamService()
			if newTablet.Type != topo.TYPE_MASTER {
				ts.StopRowCacheInvalidation()
			}
		}
	})

	mysqld := mysqlctl.NewMysqld(mycnf, dbcfgs.Dba, dbcfgs.Repl)
	if err := agent.Start(bindAddr, secureAddr, mysqld.Addr()); err != nil {
		return err
	}
	umgmt.AddCloseCallback(func() {
		agent.Stop()
	})

	// register the RPC services from the agent
	agent.RegisterQueryService(mysqld)

	return nil
}
Ejemplo n.º 7
0
// InitAgent initializes the agent within vttablet.
func InitAgent(
	tabletAlias topo.TabletAlias,
	dbcfgs *dbconfigs.DBConfigs,
	mycnf *mysqlctl.Mycnf,
	port, securePort int,
	overridesFile string,
) (agent *tabletmanager.ActionAgent, err error) {
	schemaOverrides := loadSchemaOverrides(overridesFile)

	topoServer := topo.GetServer()
	mysqld := mysqlctl.NewMysqld(mycnf, &dbcfgs.Dba, &dbcfgs.Repl)

	statsType := stats.NewString("TabletType")
	statsKeyspace := stats.NewString("TabletKeyspace")
	statsShard := stats.NewString("TabletShard")
	statsKeyRangeStart := stats.NewString("TabletKeyRangeStart")
	statsKeyRangeEnd := stats.NewString("TabletKeyRangeEnd")

	agent, err = tabletmanager.NewActionAgent(topoServer, tabletAlias, mysqld)
	if err != nil {
		return nil, err
	}

	// Start the binlog player services, not playing at start.
	agent.BinlogPlayerMap = tabletmanager.NewBinlogPlayerMap(topoServer, &dbcfgs.App.ConnectionParams, mysqld)
	tabletmanager.RegisterBinlogPlayerMap(agent.BinlogPlayerMap)

	// Action agent listens to changes in zookeeper and makes
	// modifications to this tablet.
	agent.AddChangeCallback(func(oldTablet, newTablet topo.Tablet) {
		allowQuery := true
		var shardInfo *topo.ShardInfo
		var keyspaceInfo *topo.KeyspaceInfo
		if newTablet.Type == topo.TYPE_MASTER {
			// read the shard to get SourceShards
			shardInfo, err = topoServer.GetShard(newTablet.Keyspace, newTablet.Shard)
			if err != nil {
				log.Errorf("Cannot read shard for this tablet %v: %v", newTablet.Alias, err)
			} else {
				allowQuery = len(shardInfo.SourceShards) == 0
			}

			// read the keyspace to get ShardingColumnType
			keyspaceInfo, err = topoServer.GetKeyspace(newTablet.Keyspace)
			switch err {
			case nil:
				// continue
			case topo.ErrNoNode:
				// backward compatible mode
				keyspaceInfo = topo.NewKeyspaceInfo(newTablet.Keyspace, &topo.Keyspace{})
			default:
				log.Errorf("Cannot read keyspace for this tablet %v: %v", newTablet.Alias, err)
				keyspaceInfo = nil
			}
		}

		if newTablet.IsRunningQueryService() && allowQuery {
			if dbcfgs.App.DbName == "" {
				dbcfgs.App.DbName = newTablet.DbName()
			}
			dbcfgs.App.Keyspace = newTablet.Keyspace
			dbcfgs.App.Shard = newTablet.Shard
			if newTablet.Type != topo.TYPE_MASTER {
				dbcfgs.App.EnableInvalidator = true
			} else {
				dbcfgs.App.EnableInvalidator = false
			}

			// There are a few transitions when we're
			// going to need to restart the query service:
			// - transitioning from replica to master, so clients
			//   that were already connected don't keep on using
			//   the master as replica or rdonly.
			// - having different parameters for the query
			//   service. It needs to stop and restart with the
			//   new parameters. That includes:
			//   - changing KeyRange
			//   - changing the BlacklistedTables list
			if (newTablet.Type == topo.TYPE_MASTER &&
				oldTablet.Type != topo.TYPE_MASTER) ||
				(newTablet.KeyRange != oldTablet.KeyRange) ||
				!reflect.DeepEqual(newTablet.BlacklistedTables, oldTablet.BlacklistedTables) {
				ts.DisallowQueries()
			}
			qrs := ts.LoadCustomRules()
			if newTablet.KeyRange.IsPartial() {
				qr := ts.NewQueryRule("enforce keyspace_id range", "keyspace_id_not_in_range", ts.QR_FAIL_QUERY)
				qr.AddPlanCond(sqlparser.PLAN_INSERT_PK)
				err = qr.AddBindVarCond("keyspace_id", true, true, ts.QR_NOTIN, newTablet.KeyRange)
				if err != nil {
					log.Warningf("Unable to add keyspace rule: %v", err)
				} else {
					qrs.Add(qr)
				}
			}
			if len(newTablet.BlacklistedTables) > 0 {
				log.Infof("Blacklisting tables %v", strings.Join(newTablet.BlacklistedTables, ", "))
				qr := ts.NewQueryRule("enforce blacklisted tables", "blacklisted_table", ts.QR_FAIL_QUERY)
				for _, t := range newTablet.BlacklistedTables {
					qr.AddTableCond(t)
				}
				qrs.Add(qr)
			}
			ts.AllowQueries(&dbcfgs.App, schemaOverrides, qrs, mysqld)
			// Disable before enabling to force existing streams to stop.
			binlog.DisableUpdateStreamService()
			binlog.EnableUpdateStreamService(dbcfgs)
		} else {
			ts.DisallowQueries()
			binlog.DisableUpdateStreamService()
		}

		statsType.Set(string(newTablet.Type))
		statsKeyspace.Set(newTablet.Keyspace)
		statsShard.Set(newTablet.Shard)
		statsKeyRangeStart.Set(string(newTablet.KeyRange.Start.Hex()))
		statsKeyRangeEnd.Set(string(newTablet.KeyRange.End.Hex()))

		// See if we need to start or stop any binlog player
		if newTablet.Type == topo.TYPE_MASTER {
			agent.BinlogPlayerMap.RefreshMap(newTablet, keyspaceInfo, shardInfo)
		} else {
			agent.BinlogPlayerMap.StopAllPlayersAndReset()
		}
	})

	if err := agent.Start(mysqld.Port(), port, securePort); err != nil {
		return nil, err
	}

	// register the RPC services from the agent
	agent.RegisterQueryService()

	// start health check if needed
	initHeathCheck(agent)

	return agent, nil
}