Пример #1
0
func getClusterName(clusterAlias string, instanceKey *inst.InstanceKey) (clusterName string) {
	var err error
	if clusterAlias != "" {
		clusterName, err = inst.ReadClusterByAlias(clusterAlias)
		if err != nil {
			log.Fatale(err)
		}
	} else {
		// deduce cluster by instance
		if instanceKey == nil {
			instanceKey = thisInstanceKey
		}
		if instanceKey == nil {
			log.Fatalf("Unable to get cluster instances: unresolved instance")
		}
		instance, _, err := inst.ReadInstance(instanceKey)
		if err != nil {
			log.Fatale(err)
		}
		if instance == nil {
			log.Fatalf("Instance not found: %+v", *instanceKey)
		}
		clusterName = instance.ClusterName
	}
	if clusterName == "" {
		log.Fatalf("Unable to determine cluster name")
	}
	return clusterName
}
Пример #2
0
// deployIfNotAlreadyDeployed will issue given sql queries that are not already known to be deployed.
// This iterates both lists (to-run and already-deployed) and also verifies no contraditions.
func deployIfNotAlreadyDeployed(db *sql.DB, queries []string, deployedQueries []string, deploymentType string, fatalOnError bool) error {
	tx, err := db.Begin()
	if err != nil {
		log.Fatale(err)
	}
	// Ugly workaround ahead.
	// Origin of this workaround is the existence of some "timestamp NOT NULL," column definitions,
	// where in NO_ZERO_IN_DATE,NO_ZERO_DATE sql_mode are invalid (since default is implicitly "0")
	// This means installation of orchestrator fails on such configured servers, and in particular on 5.7
	// where this setting is the dfault.
	// For purpose of backwards compatability, what we do is force sql_mode to be more relaxed, create the schemas
	// along with the "invalid" definition, and then go ahead and fix those definitions via following ALTER statements.
	// My bad.
	originalSqlMode := ""
	err = tx.QueryRow(`select @@session.sql_mode`).Scan(&originalSqlMode)
	if _, err := tx.Exec(`set @@session.sql_mode=REPLACE(@@session.sql_mode, 'NO_ZERO_DATE', '')`); err != nil {
		log.Fatale(err)
	}
	if _, err := tx.Exec(`set @@session.sql_mode=REPLACE(@@session.sql_mode, 'NO_ZERO_IN_DATE', '')`); err != nil {
		log.Fatale(err)
	}

	for i, query := range queries {
		queryAlreadyExecuted := false
		// While iterating 'queries', also iterate 'deployedQueries'. Expect identity
		if len(deployedQueries) > i {
			if deployedQueries[i] != query {
				log.Fatalf("initOrchestratorDB() PANIC: non matching %s queries between deployment requests and _orchestrator_db_deployment. Please execute 'orchestrator -c reset-internal-db-deployment'", deploymentType)
			}
			queryAlreadyExecuted = true
		}
		if queryAlreadyExecuted {
			continue
		}
		if i == 0 {
			log.Debugf("sql_mode is: %+v", originalSqlMode)
		}
		if config.Config.SmartOrchestratorDatabaseUpdate {
			log.Debugf("initOrchestratorDB executing: %.80s", strings.TrimSpace(strings.Replace(query, "\n", "", -1)))
		}

		if fatalOnError {
			if _, err := tx.Exec(query); err != nil {
				return log.Fatalf("Cannot initiate orchestrator: %+v", err)
			}
		} else {
			tx.Exec(query)
			// And ignore any error
		}
		writeInternalDeployment(db, deploymentType, query, i)
	}
	if _, err := tx.Exec(`set session sql_mode=?`, originalSqlMode); err != nil {
		log.Fatale(err)
	}
	if err := tx.Commit(); err != nil {
		log.Fatale(err)
	}
	return nil
}
Пример #3
0
// ResetInternalDeployment will clear existing deployment history (and the effect will be a complete re-deployment
// the next run). This is made available for possible operational errors, a red button
func ResetInternalDeployment() error {
	db, err := OpenOrchestrator()
	if err != nil {
		log.Fatalf("Cannot reset orchestrator internal deployment: %+v", err)
	}
	if _, err := execInternal(db, `delete from _orchestrator_db_deployment`); err != nil {
		log.Fatalf("Unable to clear _orchestrator_db_deployment: %+v", err)
	}
	return nil
}
Пример #4
0
func init() {
	var err error
	ThisHostname, err = os.Hostname()
	if err != nil {
		log.Fatalf("Cannot resolve self hostname; required. Aborting. %+v", err)
	}
}
Пример #5
0
// Create a TLS configuration from the config supplied CA, Certificate, and Private key.
// Register the TLS config with the mysql drivers as the "orchestrator" config
// Modify the supplied URI to call the TLS config
func SetupMySQLOrchestratorTLS(uri string) (string, error) {
	if !orchestratorTLSConfigured {
		tlsConfig, err := ssl.NewTLSConfig(config.Config.MySQLOrchestratorSSLCAFile, true)
		// Drop to TLS 1.0 for talking to MySQL
		tlsConfig.MinVersion = tls.VersionTLS10
		if err != nil {
			return "", log.Fatalf("Can't create TLS configuration for Orchestrator connection %s: %s", uri, err)
		}
		tlsConfig.InsecureSkipVerify = config.Config.MySQLOrchestratorSSLSkipVerify
		if err = ssl.AppendKeyPair(tlsConfig, config.Config.MySQLOrchestratorSSLCertFile, config.Config.MySQLOrchestratorSSLPrivateKeyFile); err != nil {
			return "", log.Fatalf("Can't setup TLS key pairs for %s: %s", uri, err)
		}
		if err = mysql.RegisterTLSConfig("orchestrator", tlsConfig); err != nil {
			return "", log.Fatalf("Can't register mysql TLS config for orchestrator: %s", err)
		}
		orchestratorTLSConfigured = true
	}
	return fmt.Sprintf("%s&tls=orchestrator", uri), nil
}
Пример #6
0
// readInternalDeployments reads orchestrator db deployment statements that are known to have been executed
func readInternalDeployments() (baseDeployments []string, patchDeployments []string, err error) {
	if !config.Config.SmartOrchestratorDatabaseUpdate {
		return baseDeployments, patchDeployments, nil
	}
	query := fmt.Sprintf(`
		select 
			deployment_type, 
			sql_statement  
		from 
			_orchestrator_db_deployment
		order by
			deployment_id
		`)
	db, err := OpenOrchestrator()
	if err != nil {
		log.Fatalf("Cannot initiate orchestrator internal deployment: %+v", err)
	}

	err = sqlutils.QueryRowsMap(db, query, func(m sqlutils.RowMap) error {
		deploymentType := m.GetString("deployment_type")
		sqlStatement := m.GetString("sql_statement")

		if deploymentType == "base" {
			baseDeployments = append(baseDeployments, sqlStatement)
		} else if deploymentType == "patch" {
			patchDeployments = append(patchDeployments, sqlStatement)
		} else {
			log.Fatalf("Unknown deployment type (%+v) encountered in _orchestrator_db_deployment", deploymentType)
		}

		return nil
	})
	if err != nil {
		log.Debugf("Deploying internal orchestrator tables to fix the above; this is a one time operation")
		// Table does not exist? Create it for first time
		for _, query := range internalDBDeploymentSQL {
			if _, err = execInternal(db, query); err != nil {
				log.Fatalf("Cannot initiate orchestrator internal deployment: %+v", err)
			}
		}
	}
	return baseDeployments, patchDeployments, nil
}
Пример #7
0
func postReadAdjustments() {
	if Config.MySQLOrchestratorCredentialsConfigFile != "" {
		mySQLConfig := struct {
			Client struct {
				User     string
				Password string
			}
		}{}
		err := gcfg.ReadFileInto(&mySQLConfig, Config.MySQLOrchestratorCredentialsConfigFile)
		if err != nil {
			log.Fatalf("Failed to parse gcfg data from file: %+v", err)
		} else {
			log.Debugf("Parsed orchestrator credentials from %s", Config.MySQLOrchestratorCredentialsConfigFile)
			Config.MySQLOrchestratorUser = mySQLConfig.Client.User
			Config.MySQLOrchestratorPassword = mySQLConfig.Client.Password
		}
	}
	if Config.MySQLTopologyCredentialsConfigFile != "" {
		mySQLConfig := struct {
			Client struct {
				User     string
				Password string
			}
		}{}
		err := gcfg.ReadFileInto(&mySQLConfig, Config.MySQLTopologyCredentialsConfigFile)
		if err != nil {
			log.Fatalf("Failed to parse gcfg data from file: %+v", err)
		} else {
			log.Debugf("Parsed topology credentials from %s", Config.MySQLTopologyCredentialsConfigFile)
			Config.MySQLTopologyUser = mySQLConfig.Client.User
			Config.MySQLTopologyPassword = mySQLConfig.Client.Password
		}
	}
	if Config.RecoveryPeriodBlockSeconds == 0 && Config.RecoveryPeriodBlockMinutes > 0 {
		// RecoveryPeriodBlockSeconds is a newer addition that overrides RecoveryPeriodBlockMinutes
		// The code does not consider RecoveryPeriodBlockMinutes anymore, but RecoveryPeriodBlockMinutes
		// still supported in config file for backwards compatibility
		Config.RecoveryPeriodBlockSeconds = Config.RecoveryPeriodBlockMinutes * 60
	}
}
Пример #8
0
// writeInternalDeployment will persist a successful deployment
func writeInternalDeployment(db *sql.DB, deploymentType string, sqlStatement string, statementIndex int) error {
	if !config.Config.SmartOrchestratorDatabaseUpdate {
		return nil
	}
	query := `
        	insert ignore into _orchestrator_db_deployment (
				deployment_type, sql_statement, statement_digest, statement_index) VALUES (
				?, ?, CONCAT(SHA1(?), ':', LEFT(REPLACE(REPLACE(REPLACE(?, ' ', ''), '\n', ' '), '\t', ''), 60)), ?)
				`
	if _, err := execInternal(db, query, deploymentType, sqlStatement, sqlStatement, sqlStatement, statementIndex); err != nil {
		log.Fatalf("Unable to write to _orchestrator_db_deployment: %+v", err)
	}
	return nil
}
Пример #9
0
// main is the application's entry point. It will either spawn a CLI or HTTP itnerfaces.
func main() {
	configFile := flag.String("config", "", "config file name")
	command := flag.String("c", "", "command, required. See full list of commands via 'orchestrator -c help'")
	strict := flag.Bool("strict", false, "strict mode (more checks, slower)")
	instance := flag.String("i", "", "instance, host_fqdn[:port] (e.g. db.company.com:3306, db.company.com)")
	sibling := flag.String("s", "", "sibling instance, host_fqdn[:port]")
	destination := flag.String("d", "", "destination instance, host_fqdn[:port] (synonym to -s)")
	owner := flag.String("owner", "", "operation owner")
	reason := flag.String("reason", "", "operation reason")
	duration := flag.String("duration", "", "maintenance duration (format: 59s, 59m, 23h, 6d, 4w)")
	pattern := flag.String("pattern", "", "regular expression pattern")
	clusterAlias := flag.String("alias", "", "cluster alias")
	pool := flag.String("pool", "", "Pool logical name (applies for pool-related commands)")
	hostnameFlag := flag.String("hostname", "", "Hostname/fqdn/CNAME/VIP (applies for hostname/resolve related commands)")
	discovery := flag.Bool("discovery", true, "auto discovery mode")
	quiet := flag.Bool("quiet", false, "quiet")
	verbose := flag.Bool("verbose", false, "verbose")
	debug := flag.Bool("debug", false, "debug mode (very verbose)")
	stack := flag.Bool("stack", false, "add stack trace upon error")
	config.RuntimeCLIFlags.Databaseless = flag.Bool("databaseless", false, "EXPERIMENTAL! Work without backend database")
	config.RuntimeCLIFlags.SkipUnresolve = flag.Bool("skip-unresolve", false, "Do not unresolve a host name")
	config.RuntimeCLIFlags.SkipUnresolveCheck = flag.Bool("skip-unresolve-check", false, "Skip/ignore checking an unresolve mapping (via hostname_unresolve table) resolves back to same hostname")
	config.RuntimeCLIFlags.Noop = flag.Bool("noop", false, "Dry run; do not perform destructing operations")
	config.RuntimeCLIFlags.BinlogFile = flag.String("binlog", "", "Binary log file name")
	config.RuntimeCLIFlags.GrabElection = flag.Bool("grab-election", false, "Grab leadership (only applies to continuous mode)")
	flag.Parse()

	if *destination != "" && *sibling != "" {
		log.Fatalf("-s and -d are synonyms, yet both were specified. You're probably doing the wrong thing.")
	}
	if *destination == "" {
		*destination = *sibling
	}

	log.SetLevel(log.ERROR)
	if *verbose {
		log.SetLevel(log.INFO)
	}
	if *debug {
		log.SetLevel(log.DEBUG)
	}
	if *stack {
		log.SetPrintStackTrace(*stack)
	}
	log.Info("starting")

	runtime.GOMAXPROCS(math.MinInt(4, runtime.NumCPU()))

	if len(*configFile) > 0 {
		config.ForceRead(*configFile)
	} else {
		config.Read("/etc/orchestrator.conf.json", "conf/orchestrator.conf.json", "orchestrator.conf.json")
	}
	if *config.RuntimeCLIFlags.Databaseless {
		config.Config.DatabaselessMode__experimental = true
	}
	if config.Config.Debug {
		log.SetLevel(log.DEBUG)
	}
	if *quiet {
		// Override!!
		log.SetLevel(log.ERROR)
	}
	if config.Config.EnableSyslog {
		log.EnableSyslogWriter("orchestrator")
		log.SetSyslogLevel(log.INFO)
	}
	if config.Config.AuditToSyslog {
		inst.EnableAuditSyslog()
	}

	if len(flag.Args()) == 0 && *command == "" {
		// No command, no argument: just prompt
		fmt.Println(prompt)
		return
	}

	switch {
	case len(flag.Args()) == 0 || flag.Arg(0) == "cli":
		app.CliWrapper(*command, *strict, *instance, *destination, *owner, *reason, *duration, *pattern, *clusterAlias, *pool, *hostnameFlag)
	case flag.Arg(0) == "http":
		app.Http(*discovery)
	default:
		fmt.Fprintln(os.Stderr, `Usage: 
  orchestrator --options... [cli|http]
See complete list of commands:
  orchestrator -c help
Full blown documentation:
  orchestrator
`)
		os.Exit(1)
	}
}
Пример #10
0
// Cli initiates a command line interface, executing requested command.
func Cli(command string, strict bool, instance string, destination string, owner string, reason string, duration string, pattern string, clusterAlias string, pool string, hostnameFlag string) {
	if instance != "" && !strings.Contains(instance, ":") {
		instance = fmt.Sprintf("%s:%d", instance, config.Config.DefaultInstancePort)
	}
	instanceKey, err := inst.ParseInstanceKey(instance)
	if err != nil {
		instanceKey = nil
	}
	rawInstanceKey, err := inst.NewRawInstanceKey(instance)
	if err != nil {
		rawInstanceKey = nil
	}

	if destination != "" && !strings.Contains(destination, ":") {
		destination = fmt.Sprintf("%s:%d", destination, config.Config.DefaultInstancePort)
	}
	destinationKey, err := inst.ParseInstanceKey(destination)
	if err != nil {
		destinationKey = nil
	}

	if hostname, err := os.Hostname(); err == nil {
		thisInstanceKey = &inst.InstanceKey{Hostname: hostname, Port: int(config.Config.DefaultInstancePort)}
	}
	postponedFunctionsContainer := inst.NewPostponedFunctionsContainer()

	if len(owner) == 0 {
		// get os username as owner
		usr, err := user.Current()
		if err != nil {
			log.Fatale(err)
		}
		owner = usr.Username
	}
	inst.SetMaintenanceOwner(owner)

	skipDatabaseCommands := false
	switch command {
	case "reset-internal-db-deployment":
		skipDatabaseCommands = true
	case "help":
		skipDatabaseCommands = true
	}

	if !skipDatabaseCommands {
		process.ContinuousRegistration(string(process.OrchestratorExecutionCliMode), command)
	}
	// begin commands
	switch command {
	// smart mode
	case registerCliCommand("relocate", "Smart relocation", `Relocate a slave beneath another instance`), registerCliCommand("relocate-below", "Smart relocation", `Synonym to 'relocate', will be deprecated`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination:", destination)
			}
			_, err := inst.RelocateBelow(instanceKey, destinationKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), destinationKey.DisplayString()))
		}
	case registerCliCommand("relocate-slaves", "Smart relocation", `Relocates all or part of the slaves of a given instance under another instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination:", destination)
			}
			slaves, _, err, errs := inst.RelocateSlaves(instanceKey, destinationKey, pattern)
			if err != nil {
				log.Fatale(err)
			} else {
				for _, e := range errs {
					log.Errore(e)
				}
				for _, slave := range slaves {
					fmt.Println(slave.Key.DisplayString())
				}
			}
		}
	case registerCliCommand("regroup-slaves", "Smart relocation", `Given an instance, pick one of its slave and make it local master of its siblings`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			lostSlaves, equalSlaves, aheadSlaves, promotedSlave, err := inst.RegroupSlaves(instanceKey, false, func(candidateSlave *inst.Instance) { fmt.Println(candidateSlave.Key.DisplayString()) }, postponedFunctionsContainer)
			postponedFunctionsContainer.InvokePostponed()
			if promotedSlave == nil {
				log.Fatalf("Could not regroup slaves of %+v; error: %+v", *instanceKey, err)
			}
			fmt.Println(fmt.Sprintf("%s lost: %d, trivial: %d, pseudo-gtid: %d",
				promotedSlave.Key.DisplayString(), len(lostSlaves), len(equalSlaves), len(aheadSlaves)))
			if err != nil {
				log.Fatale(err)
			}
		}
		// General replication commands
		// move, binlog file:pos
	case registerCliCommand("move-up", "Classic file:pos relocation", `Move a slave one level up the topology`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			instance, err := inst.MoveUp(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), instance.MasterKey.DisplayString()))
		}
	case registerCliCommand("move-up-slaves", "Classic file:pos relocation", `Moves slaves of the given instance one level up the topology`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			movedSlaves, _, err, errs := inst.MoveUpSlaves(instanceKey, pattern)
			if err != nil {
				log.Fatale(err)
			} else {
				for _, e := range errs {
					log.Errore(e)
				}
				for _, slave := range movedSlaves {
					fmt.Println(slave.Key.DisplayString())
				}
			}
		}
	case registerCliCommand("move-below", "Classic file:pos relocation", `Moves a slave beneath its sibling. Both slaves must be actively replicating from same master.`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination/sibling:", destination)
			}
			_, err := inst.MoveBelow(instanceKey, destinationKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), destinationKey.DisplayString()))
		}
	case registerCliCommand("move-equivalent", "Classic file:pos relocation", `Moves a slave beneath another server, based on previously recorded "equivalence coordinates"`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination:", destination)
			}
			_, err := inst.MoveEquivalent(instanceKey, destinationKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), destinationKey.DisplayString()))
		}
	case registerCliCommand("repoint", "Classic file:pos relocation", `Make the given instance replicate from another instance without changing the binglog coordinates. Use with care`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			// destinationKey can be null, in which case the instance repoints to its existing master
			instance, err := inst.Repoint(instanceKey, destinationKey, inst.GTIDHintNeutral)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), instance.MasterKey.DisplayString()))
		}
	case registerCliCommand("repoint-slaves", "Classic file:pos relocation", `Repoint all slaves of given instance to replicate back from the instance. Use with care`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			repointedSlaves, err, errs := inst.RepointSlavesTo(instanceKey, pattern, destinationKey)
			if err != nil {
				log.Fatale(err)
			} else {
				for _, e := range errs {
					log.Errore(e)
				}
				for _, slave := range repointedSlaves {
					fmt.Println(fmt.Sprintf("%s<%s", slave.Key.DisplayString(), instanceKey.DisplayString()))
				}
			}
		}
	case registerCliCommand("enslave-siblings", "Classic file:pos relocation", `Turn all siblings of a slave into its sub-slaves.`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}
			_, _, err := inst.EnslaveSiblings(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("enslave-master", "Classic file:pos relocation", `Turn an instance into a master of its own master; essentially switch the two.`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}
			_, err := inst.EnslaveMaster(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("make-co-master", "Classic file:pos relocation", `Create a master-master replication. Given instance is a slave which replicates directly from a master.`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.MakeCoMaster(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("get-candidate-slave", "Classic file:pos relocation", `Information command suggesting the most up-to-date slave of a given instance that is good for promotion`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			instance, _, _, _, err := inst.GetCandidateSlave(instanceKey, false)
			if err != nil {
				log.Fatale(err)
			} else {
				fmt.Println(instance.Key.DisplayString())
			}
		}
	case registerCliCommand("regroup-slaves-bls", "Binlog server relocation", `Regroup Binlog Server slaves of a given instance`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			_, promotedBinlogServer, err := inst.RegroupSlavesBinlogServers(instanceKey, false)
			if promotedBinlogServer == nil {
				log.Fatalf("Could not regroup binlog server slaves of %+v; error: %+v", *instanceKey, err)
			}
			fmt.Println(promotedBinlogServer.Key.DisplayString())
			if err != nil {
				log.Fatale(err)
			}
		}
	// move, GTID
	case registerCliCommand("move-gtid", "GTID relocation", `Move a slave beneath another instance.`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination:", destination)
			}
			_, err := inst.MoveBelowGTID(instanceKey, destinationKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), destinationKey.DisplayString()))
		}
	case registerCliCommand("move-slaves-gtid", "GTID relocation", `Moves all slaves of a given instance under another (destination) instance using GTID`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination:", destination)
			}
			movedSlaves, _, err, errs := inst.MoveSlavesGTID(instanceKey, destinationKey, pattern)
			if err != nil {
				log.Fatale(err)
			} else {
				for _, e := range errs {
					log.Errore(e)
				}
				for _, slave := range movedSlaves {
					fmt.Println(slave.Key.DisplayString())
				}
			}
		}
	case registerCliCommand("regroup-slaves-gtid", "GTID relocation", `Given an instance, pick one of its slave and make it local master of its siblings, using GTID.`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			lostSlaves, movedSlaves, promotedSlave, err := inst.RegroupSlavesGTID(instanceKey, false, func(candidateSlave *inst.Instance) { fmt.Println(candidateSlave.Key.DisplayString()) })
			if promotedSlave == nil {
				log.Fatalf("Could not regroup slaves of %+v; error: %+v", *instanceKey, err)
			}
			fmt.Println(fmt.Sprintf("%s lost: %d, moved: %d",
				promotedSlave.Key.DisplayString(), len(lostSlaves), len(movedSlaves)))
			if err != nil {
				log.Fatale(err)
			}
		}
		// Pseudo-GTID
	case registerCliCommand("match", "Pseudo-GTID relocation", `Matches a slave beneath another (destination) instance using Pseudo-GTID`),
		registerCliCommand("match-below", "Pseudo-GTID relocation", `Synonym to 'match', will be deprecated`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination:", destination)
			}
			_, _, err := inst.MatchBelow(instanceKey, destinationKey, true)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), destinationKey.DisplayString()))
		}
	case registerCliCommand("match-up", "Pseudo-GTID relocation", `Transport the slave one level up the hierarchy, making it child of its grandparent, using Pseudo-GTID`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			instance, _, err := inst.MatchUp(instanceKey, true)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), instance.MasterKey.DisplayString()))
		}
	case registerCliCommand("rematch", "Pseudo-GTID relocation", `Reconnect a slave onto its master, via PSeudo-GTID.`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			instance, _, err := inst.RematchSlave(instanceKey, true)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%s<%s", instanceKey.DisplayString(), instance.MasterKey.DisplayString()))
		}
	case registerCliCommand("match-slaves", "Pseudo-GTID relocation", `Matches all slaves of a given instance under another (destination) instance using Pseudo-GTID`),
		registerCliCommand("multi-match-slaves", "Pseudo-GTID relocation", `Synonym to 'match-slaves', will be deprecated`):
		{
			// Move all slaves of "instance" beneath "destination"
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}
			if destinationKey == nil {
				log.Fatal("Cannot deduce destination:", destination)
			}

			matchedSlaves, _, err, errs := inst.MultiMatchSlaves(instanceKey, destinationKey, pattern)
			if err != nil {
				log.Fatale(err)
			} else {
				for _, e := range errs {
					log.Errore(e)
				}
				for _, slave := range matchedSlaves {
					fmt.Println(slave.Key.DisplayString())
				}
			}
		}
	case registerCliCommand("match-up-slaves", "Pseudo-GTID relocation", `Matches slaves of the given instance one level up the topology, making them siblings of given instance, using Pseudo-GTID`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			matchedSlaves, _, err, errs := inst.MatchUpSlaves(instanceKey, pattern)
			if err != nil {
				log.Fatale(err)
			} else {
				for _, e := range errs {
					log.Errore(e)
				}
				for _, slave := range matchedSlaves {
					fmt.Println(slave.Key.DisplayString())
				}
			}
		}
	case registerCliCommand("regroup-slaves-pgtid", "Pseudo-GTID relocation", `Given an instance, pick one of its slave and make it local master of its siblings, using Pseudo-GTID.`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			lostSlaves, equalSlaves, aheadSlaves, promotedSlave, err := inst.RegroupSlavesPseudoGTID(instanceKey, false, func(candidateSlave *inst.Instance) { fmt.Println(candidateSlave.Key.DisplayString()) }, postponedFunctionsContainer)
			postponedFunctionsContainer.InvokePostponed()
			if promotedSlave == nil {
				log.Fatalf("Could not regroup slaves of %+v; error: %+v", *instanceKey, err)
			}
			fmt.Println(fmt.Sprintf("%s lost: %d, trivial: %d, pseudo-gtid: %d",
				promotedSlave.Key.DisplayString(), len(lostSlaves), len(equalSlaves), len(aheadSlaves)))
			if err != nil {
				log.Fatale(err)
			}
		}
		// General replication commands
	case registerCliCommand("enable-gtid", "Replication, general", `If possible, turn on GTID replication`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.EnableGTID(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("disable-gtid", "Replication, general", `Turn off GTID replication, back to file:pos replication`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.DisableGTID(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("reset-master-gtid-remove-own-uuid", "Replication, general", `Reset master on instance, remove GTID entries generated by instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.ResetMasterGTIDOperation(instanceKey, true, "")
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("skip-query", "Replication, general", `Skip a single statement on a slave; either when running with GTID or without`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.SkipQuery(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("stop-slave", "Replication, general", `Issue a STOP SLAVE on an instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.StopSlave(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("start-slave", "Replication, general", `Issue a START SLAVE on an instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.StartSlave(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("restart-slave", "Replication, general", `STOP and START SLAVE on an instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.RestartSlave(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("reset-slave", "Replication, general", `Issues a RESET SLAVE command; use with care`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.ResetSlaveOperation(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("detach-slave", "Replication, general", `Stops replication and modifies binlog position into an impossible, yet reversible, value.`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.DetachSlaveOperation(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("reattach-slave", "Replication, general", `Undo a detach-slave operation`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.ReattachSlaveOperation(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("detach-slave-master-host", "Replication, general", `Stops replication and modifies Master_Host into an impossible, yet reversible, value.`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}
			_, err := inst.DetachSlaveMasterHost(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("reattach-slave-master-host", "Replication, general", `Undo a detach-slave-master-host operation`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}
			_, err := inst.ReattachSlaveMasterHost(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("master-pos-wait", "Replication, general", `Wait until slave reaches given replication coordinates (--binlog=file:pos)`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unresolved instance")
			}
			instance, err := inst.ReadTopologyInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			if instance == nil {
				log.Fatalf("Instance not found: %+v", *instanceKey)
			}
			var binlogCoordinates *inst.BinlogCoordinates

			if binlogCoordinates, err = inst.ParseBinlogCoordinates(*config.RuntimeCLIFlags.BinlogFile); err != nil {
				log.Fatalf("Expecing --binlog argument as file:pos")
			}
			_, err = inst.MasterPosWait(instanceKey, binlogCoordinates)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
		// Pool
	case registerCliCommand("set-read-only", "Instance", `Turn an instance read-only, via SET GLOBAL read_only := 1`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.SetReadOnly(instanceKey, true)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("set-writeable", "Instance", `Turn an instance writeable, via SET GLOBAL read_only := 0`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			_, err := inst.SetReadOnly(instanceKey, false)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
		// Binary log operations
	case registerCliCommand("flush-binary-logs", "Binary logs", `Flush binary logs on an instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			var err error
			if *config.RuntimeCLIFlags.BinlogFile == "" {
				_, err = inst.FlushBinaryLogs(instanceKey, 1)
			} else {
				_, err = inst.FlushBinaryLogsTo(instanceKey, *config.RuntimeCLIFlags.BinlogFile)
			}
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("purge-binary-logs", "Binary logs", `Purge binary logs of an instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			var err error
			if *config.RuntimeCLIFlags.BinlogFile == "" {
				log.Fatal("expecting --binlog value")
			}

			_, err = inst.PurgeBinaryLogsTo(instanceKey, *config.RuntimeCLIFlags.BinlogFile)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("last-pseudo-gtid", "Binary logs", `Find latest Pseudo-GTID entry in instance's binary logs`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unresolved instance")
			}
			instance, err := inst.ReadTopologyInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			if instance == nil {
				log.Fatalf("Instance not found: %+v", *instanceKey)
			}
			coordinates, text, err := inst.FindLastPseudoGTIDEntry(instance, instance.RelaylogCoordinates, nil, strict, nil)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%+v:%s", *coordinates, text))
		}
	case registerCliCommand("find-binlog-entry", "Binary logs", `Get binlog file:pos of entry given by --pattern (exact full match, not a regular expression) in a given instance`):
		{
			if pattern == "" {
				log.Fatal("No pattern given")
			}
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unresolved instance")
			}
			instance, err := inst.ReadTopologyInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			if instance == nil {
				log.Fatalf("Instance not found: %+v", *instanceKey)
			}
			coordinates, err := inst.SearchEntryInInstanceBinlogs(instance, pattern, false)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%+v", *coordinates))
		}
	case registerCliCommand("correlate-binlog-pos", "Binary logs", `Given an instance (-i) and binlog coordinates (--binlog=file:pos), find the correlated coordinates in another instance (-d)`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unresolved instance")
			}
			instance, err := inst.ReadTopologyInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			if instance == nil {
				log.Fatalf("Instance not found: %+v", *instanceKey)
			}
			if !instance.LogBinEnabled {
				log.Fatalf("Instance does not have binary logs: %+v", *instanceKey)
			}
			if destinationKey == nil {
				log.Fatal("Cannot deduce target instance:", destination)
			}
			otherInstance, err := inst.ReadTopologyInstance(destinationKey)
			if err != nil {
				log.Fatale(err)
			}
			if otherInstance == nil {
				log.Fatalf("Instance not found: %+v", *destinationKey)
			}
			var binlogCoordinates *inst.BinlogCoordinates
			if *config.RuntimeCLIFlags.BinlogFile == "" {
				binlogCoordinates = &instance.SelfBinlogCoordinates
			} else {
				if binlogCoordinates, err = inst.ParseBinlogCoordinates(*config.RuntimeCLIFlags.BinlogFile); err != nil {
					log.Fatalf("Expecing --binlog argument as file:pos")
				}
			}

			coordinates, _, err := inst.CorrelateBinlogCoordinates(instance, binlogCoordinates, otherInstance)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%+v", *coordinates))
		}
		// Pool
	case registerCliCommand("submit-pool-instances", "Pools", `Submit a pool name with a list of instances in that pool`):
		{
			if pool == "" {
				log.Fatal("Please submit --pool")
			}
			err := inst.ApplyPoolInstances(pool, instance)
			if err != nil {
				log.Fatale(err)
			}
		}
	case registerCliCommand("cluster-pool-instances", "Pools", `List all pools and their associated instances`):
		{
			clusterPoolInstances, err := inst.ReadAllClusterPoolInstances()
			if err != nil {
				log.Fatale(err)
			}
			for _, clusterPoolInstance := range clusterPoolInstances {
				fmt.Println(fmt.Sprintf("%s\t%s\t%s\t%s:%d", clusterPoolInstance.ClusterName, clusterPoolInstance.ClusterAlias, clusterPoolInstance.Pool, clusterPoolInstance.Hostname, clusterPoolInstance.Port))
			}
		}
		// Information
	case registerCliCommand("find", "Information", `Find instances whose hostname matches given regex pattern`):
		{
			if pattern == "" {
				log.Fatal("No pattern given")
			}
			instances, err := inst.FindInstances(pattern)
			if err != nil {
				log.Fatale(err)
			} else {
				for _, instance := range instances {
					fmt.Println(instance.Key.DisplayString())
				}
			}
		}
	case registerCliCommand("clusters", "Information", `List all clusters known to orchestrator`):
		{
			clusters, err := inst.ReadClusters()
			if err != nil {
				log.Fatale(err)
			} else {
				fmt.Println(strings.Join(clusters, "\n"))
			}
		}
	case registerCliCommand("topology", "Information", `Show an ascii-graph of a replication topology, given a member of that topology`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			output, err := inst.ASCIITopology(instanceKey, pattern)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(output)
		}
	case registerCliCommand("which-instance", "Information", `Output the fully-qualified hostname:port representation of the given instance, or error if unknown`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unable to get master: unresolved instance")
			}
			instance, _, err := inst.ReadInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			if instance == nil {
				log.Fatalf("Instance not found: %+v", *instanceKey)
			}
			fmt.Println(instance.Key.DisplayString())
		}
	case registerCliCommand("which-cluster", "Information", `Output the name of the cluster an instance belongs to, or error if unknown to orchestrator`):
		{
			clusterName := getClusterName(clusterAlias, instanceKey)
			fmt.Println(clusterName)
		}
	case registerCliCommand("which-cluster-instances", "Information", `Output the list of instances participating in same cluster as given instance`):
		{
			clusterName := getClusterName(clusterAlias, instanceKey)
			instances, err := inst.ReadClusterInstances(clusterName)
			if err != nil {
				log.Fatale(err)
			}
			for _, clusterInstance := range instances {
				fmt.Println(clusterInstance.Key.DisplayString())
			}
		}
	case registerCliCommand("which-cluster-osc-slaves", "Information", `Output a list of slaves in same cluster as given instance, that could serve as a pt-online-schema-change operation control slaves`):
		{
			clusterName := getClusterName(clusterAlias, instanceKey)
			instances, err := inst.GetClusterOSCSlaves(clusterName)
			if err != nil {
				log.Fatale(err)
			}
			for _, clusterInstance := range instances {
				fmt.Println(clusterInstance.Key.DisplayString())
			}
		}
	case registerCliCommand("which-master", "Information", `Output the fully-qualified hostname:port representation of a given instance's master`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unable to get master: unresolved instance")
			}
			instance, _, err := inst.ReadInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			if instance == nil {
				log.Fatalf("Instance not found: %+v", *instanceKey)
			}
			fmt.Println(instance.MasterKey.DisplayString())
		}
	case registerCliCommand("which-slaves", "Information", `Output the fully-qualified hostname:port list of slaves of a given instance`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unable to get slaves: unresolved instance")
			}
			slaves, err := inst.ReadSlaveInstances(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			for _, slave := range slaves {
				fmt.Println(slave.Key.DisplayString())
			}
		}
	case registerCliCommand("instance-status", "Information", `Output short status on a given instance`):
		{
			if instanceKey == nil {
				instanceKey = assignThisInstanceKey()
			}
			if instanceKey == nil {
				log.Fatalf("Unable to get status: unresolved instance")
			}
			instance, _, err := inst.ReadInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			if instance == nil {
				log.Fatalf("Instance not found: %+v", *instanceKey)
			}
			fmt.Println(instance.HumanReadableDescription())
		}
	case registerCliCommand("get-cluster-heuristic-lag", "Information", `For a given cluster (indicated by an instance or alias), output a heuristic "representative" lag of that cluster`):
		{
			clusterName := getClusterName(clusterAlias, instanceKey)
			lag, err := inst.GetClusterHeuristicLag(clusterName)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(lag)
		}
		// Instance management
	case registerCliCommand("discover", "Instance management", `Lookup an instance, investigate it`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			instance, err := inst.ReadTopologyInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instance.Key.DisplayString())
		}
	case registerCliCommand("forget", "Instance management", `Forget about an instance's existence`):
		{
			if rawInstanceKey == nil {
				rawInstanceKey = assignThisInstanceKey()
			}
			if rawInstanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}
			err := inst.ForgetInstance(rawInstanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(rawInstanceKey.DisplayString())
		}
	case registerCliCommand("begin-maintenance", "Instance management", `Request a maintenance lock on an instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if reason == "" {
				log.Fatal("--reason option required")
			}
			var durationSeconds int = 0
			if duration != "" {
				durationSeconds, err = util.SimpleTimeToSeconds(duration)
				if err != nil {
					log.Fatale(err)
				}
				if durationSeconds < 0 {
					log.Fatalf("Duration value must be non-negative. Given value: %d", durationSeconds)
				}
			}
			maintenanceKey, err := inst.BeginBoundedMaintenance(instanceKey, inst.GetMaintenanceOwner(), reason, uint(durationSeconds))
			if err == nil {
				log.Infof("Maintenance key: %+v", maintenanceKey)
				log.Infof("Maintenance duration: %d seconds", durationSeconds)
			}
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("end-maintenance", "Instance management", `Remove maintenance lock from an instance`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			err := inst.EndMaintenanceByInstanceKey(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("begin-downtime", "Instance management", `Mark an instance as downtimed`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			if reason == "" {
				log.Fatal("--reason option required")
			}
			var durationSeconds int = 0
			if duration != "" {
				durationSeconds, err = util.SimpleTimeToSeconds(duration)
				if err != nil {
					log.Fatale(err)
				}
				if durationSeconds < 0 {
					log.Fatalf("Duration value must be non-negative. Given value: %d", durationSeconds)
				}
			}
			err := inst.BeginDowntime(instanceKey, inst.GetMaintenanceOwner(), reason, uint(durationSeconds))
			if err == nil {
				log.Infof("Downtime duration: %d seconds", durationSeconds)
			} else {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("end-downtime", "Instance management", `Indicate an instance is no longer downtimed`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			err := inst.EndDowntime(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
		// Recovery & analysis
	case registerCliCommand("recover", "Recovery", `Do auto-recovery given a dead instance`), registerCliCommand("recover-lite", "Recovery", `Do auto-recovery given a dead instance. Orchestrator chooses the best course of actionwithout executing external processes`):
		{
			if instanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}

			recoveryAttempted, promotedInstanceKey, err := logic.CheckAndRecover(instanceKey, destinationKey, (command == "recover-lite"))
			if err != nil {
				log.Fatale(err)
			}
			if recoveryAttempted {
				if promotedInstanceKey == nil {
					log.Fatalf("Recovery attempted yet no slave promoted")
				}
				fmt.Println(promotedInstanceKey.DisplayString())
			}
		}
	case registerCliCommand("replication-analysis", "Recovery", `Request an analysis of potential crash incidents in all known topologies`):
		{
			analysis, err := inst.GetReplicationAnalysis("", false, false)
			if err != nil {
				log.Fatale(err)
			}
			for _, entry := range analysis {
				fmt.Println(fmt.Sprintf("%s (cluster %s): %s", entry.AnalyzedInstanceKey.DisplayString(), entry.ClusterDetails.ClusterName, entry.Analysis))
			}
		}
	case registerCliCommand("ack-cluster-recoveries", "Recovery", `Acknowledge recoveries for a given cluster; this unblocks pending future recoveries`):
		{
			if reason == "" {
				log.Fatal("--reason option required (comment your ack)")
			}
			clusterName := getClusterName(clusterAlias, instanceKey)
			countRecoveries, err := logic.AcknowledgeClusterRecoveries(clusterName, inst.GetMaintenanceOwner(), reason)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%d recoveries acknowldged", countRecoveries))
		}
	case registerCliCommand("ack-instance-recoveries", "Recovery", `Acknowledge recoveries for a given instance; this unblocks pending future recoveries`):
		{
			if reason == "" {
				log.Fatal("--reason option required (comment your ack)")
			}
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)

			countRecoveries, err := logic.AcknowledgeInstanceRecoveries(instanceKey, inst.GetMaintenanceOwner(), reason)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(fmt.Sprintf("%d recoveries acknowldged", countRecoveries))
		}
	// Instance meta
	case registerCliCommand("register-candidate", "Instance, meta", `Indicate that a specific instance is a preferred candidate for master promotion`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			err := inst.RegisterCandidateInstance(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("register-hostname-unresolve", "Instance, meta", `Assigns the given instance a virtual (aka "unresolved") name`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			err := inst.RegisterHostnameUnresolve(instanceKey, hostnameFlag)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
	case registerCliCommand("deregister-hostname-unresolve", "Instance, meta", `Explicitly deregister/dosassociate a hostname with an "unresolved" name`):
		{
			instanceKey = deduceInstanceKeyIfNeeded(instance, instanceKey)
			err := inst.DeregisterHostnameUnresolve(instanceKey)
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println(instanceKey.DisplayString())
		}
		// meta
	case registerCliCommand("snapshot-topologies", "Meta", `Take a snapshot of existing topologies.`):
		{
			err := inst.SnapshotTopologies()
			if err != nil {
				log.Fatale(err)
			}
		}
	case registerCliCommand("continuous", "Meta", `Enter continuous mode, and actively poll for instances, diagnose problems, do maintenance`):
		{
			logic.ContinuousDiscovery()
		}
	case registerCliCommand("resolve", "Meta", `Resolve given hostname`):
		{
			if rawInstanceKey == nil {
				log.Fatal("Cannot deduce instance:", instance)
			}
			if conn, err := net.Dial("tcp", rawInstanceKey.DisplayString()); err == nil {
				log.Debugf("tcp test is good; got connection %+v", conn)
				conn.Close()
			} else {
				log.Fatale(err)
			}
			if cname, err := inst.GetCNAME(rawInstanceKey.Hostname); err == nil {
				log.Debugf("GetCNAME() %+v, %+v", cname, err)
				rawInstanceKey.Hostname = cname
				fmt.Println(rawInstanceKey.DisplayString())
			} else {
				log.Fatale(err)
			}
		}
	case registerCliCommand("reset-hostname-resolve-cache", "Meta", `Clear the hostname resolve cache`):
		{
			err := inst.ResetHostnameResolveCache()
			if err != nil {
				log.Fatale(err)
			}
			fmt.Println("hostname resolve cache cleared")
		}
	case registerCliCommand("reset-internal-db-deployment", "Meta, internal", `Clear internal db deployment history, use if somehow corrupted internal deployment history`):
		{
			config.Config.SkipOrchestratorDatabaseUpdate = true
			db.ResetInternalDeployment()
			fmt.Println("Internal db deployment history reset. Next orchestrator execution will rebuild internal db structure (no data will be lost)")
		}
		// Help
	case "help":
		{
			fmt.Fprintf(os.Stderr, availableCommandsUsage())
		}
	default:
		log.Fatalf("Unknown command: \"%s\". %s", command, availableCommandsUsage())
	}
}