website/content/en/docs/15.0/reference/programs/vttablet.md

title	aliases
vttablet	/docs/user-guides/vttablet-modes/ /docs/reference/vttablet-modes/

A VTTablet server controls a running MySQL server. VTTablet supports two primary types of deployments:

• Managed MySQL (most common)
• External MySQL

In addition to these deployment types, a partially managed VTTablet is also possible by setting --disable_active_reparents.

Example Usage

Managed MySQL

In this mode, Vitess actively manages MySQL:

export TOPOLOGY_FLAGS="--topo_implementation etcd2 --topo_global_server_address localhost:2379 --topo_global_root /vitess/global"
export VTDATAROOT="/tmp"

vttablet \
$TOPOLOGY_FLAGS
--tablet-path $alias
--init_keyspace $keyspace
--init_shard $shard
--init_tablet_type $tablet_type
--port $port
--grpc_port $grpc_port
--service_map 'grpc-queryservice,grpc-tabletmanager,grpc-updatestream'

$alias needs to be of the form: <cell>-id, and the cell should match one of the local cells that was created in the topology. The id can be left padded with zeroes: cell-100 and cell-000000100 are synonymous.

External MySQL

In this mode, an external MySQL can be used such as AWS RDS, AWS Aurora, Google CloudSQL; or just an existing (vanilla) MySQL installation.

See Unmanaged Tablet for the full guide.

Even if a MySQL is external, you can still make vttablet perform some management functions. They are as follows:

• --disable_active_reparents: If this flag is set, then any reparent or replica commands will not be allowed. These are InitShardMaster, PlannedReparent, PlannedReparent, EmergencyReparent, and ReparentTablet. In this mode, you should use the TabletExternallyReparented command to inform vitess of the current primary.
• --replication_connect_retry: This value is give to mysql when it connects a replica to the primary as the retry duration parameter.
• --enable_replication_reporter: If this flag is set, then vttablet will transmit replica lag related information to the vtgates, which will allow it to balance load better. Additionally, enabling this will also cause vttablet to restart replication if it was stopped. However, it will do this only if --disable_active_reparents was not turned on.
• --heartbeat_enable and --heartbeat interval duration: cause vttablet to write heartbeats to the sidecar database. This information is also used by the replication reporter to assess replica lag.

Options

The following global options apply to vttablet:

Name	Type	Definition
--alsologtostderr	boolean	log to standard error as well as files
--app_idle_timeout	duration	Idle timeout for app connections (default 1m0s)
--app_pool_size	int	Size of the connection pool for app connections (default 40)
--azblob_backup_account_key_file	string	Path to a file containing the Azure Storage account key; if this flag is unset, the environment variable VT_AZBLOB_ACCOUNT_KEY will be used as the key itself (NOT a file path)
--azblob_backup_account_name	string	Azure Storage Account name for backups; if this flag is unset, the environment variable VT_AZBLOB_ACCOUNT_NAME will be used
--azblob_backup_container_name	string	Azure Blob Container Name
--azblob_backup_parallelism	int	Azure Blob operation parallelism (requires extra memory when increased) (default 1)
--azblob_backup_storage_root	string	Root prefix for all backup-related Azure Blobs; this should exclude both initial and trailing '/' (e.g. just 'a/b' not '/a/b/')
--backup_engine_implementation	string	Specifies which implementation to use for creating new backups (builtin or xtrabackup). Restores will always be done with whichever engine created a given backup. (default "builtin")
--backup_storage_block_size	int	if backup_storage_compress is true, backup_storage_block_size sets the byte size for each block while compressing (default is 250000). (default 250000)
--backup_storage_compress		if set, the backup files will be compressed (default is true). Set to false for instance if a backup_storage_hook is specified and it compresses the data. (default true)
--backup_storage_hook	string	if set, we send the contents of the backup files through this hook.
--backup_storage_implementation	string	which implementation to use for the backup storage feature
--backup_storage_number_blocks	int	if backup_storage_compress is true, backup_storage_number_blocks sets the number of blocks that can be processed, at once, before the writer blocks, during compression (default is 2). It should be equal to the number of CPUs available for compression (default 2)
--binlog_player_grpc_ca	string	the server ca to use to validate servers when connecting
--binlog_player_grpc_cert	string	the cert to use to connect
--binlog_player_grpc_key	string	the key to use to connect
--binlog_player_grpc_server_name	string	the server name to use to validate server certificate
--binlog_player_protocol	string	the protocol to download binlogs from a vttablet (default "grpc")
--binlog_use_v3_resharding_mode		True iff the binlog streamer should use V3-style sharding, which doesn't require a preset sharding key column. (default true)
--ceph_backup_storage_config	string	Path to JSON config file for ceph backup storage (default "ceph_backup_config.json")
--consul_auth_static_file	string	JSON File to read the topos/tokens from.
--cpu_profile	string	write cpu profile to file
--datadog-agent-host	string	host to send spans to. if empty, no tracing will be done
--datadog-agent-port	string	port to send spans to. if empty, no tracing will be done
--db-credentials-file	string	db credentials file; send SIGHUP to reload this file
--db-credentials-server	string	db credentials server type (use 'file' for the file implementation) (default "file")
--db_allprivs_password	string	db allprivs password
--db_allprivs_use_ssl		Set this flag to false to make the allprivs connection to not use SSL (default true)
--db_allprivs_user	string	db allprivs user userKey (default "vt_allprivs")
--db_app_password	string	db app password
--db_app_use_ssl		Set this flag to false to make the app connection to not use SSL (default true)
--db_app_user	string	db app user userKey. Used for VReplication. (default "vt_app")
--db_appdebug_password	string	db appdebug password
--db_appdebug_use_ssl		Set this flag to false to make the appdebug connection to not use SSL (default true)
--db_appdebug_user	string	db appdebug user userKey (default "vt_appdebug")
--db_charset	string	Sets the character set for the connection.
--db_connect_timeout_ms	int	connection timeout to mysqld in milliseconds (0 for no timeout)
--db_dba_password	string	db dba password
--db_dba_use_ssl		Set this flag to false to make the dba connection to not use SSL (default true)
--db_dba_user	string	db dba user userKey (default "vt_dba")
--db_erepl_password	string	db erepl password
--db_erepl_use_ssl		Set this flag to false to make the erepl connection to not use SSL (default true)
--db_erepl_user	string	db erepl user userKey (default "vt_erepl")
--db_filtered_password	string	db filtered password
--db_filtered_use_ssl		Set this flag to false to make the filtered connection to not use SSL (default true)
--db_filtered_user	string	db filtered user userKey (default "vt_filtered")
--db_flags	uint	Flag values as defined by MySQL.
--db_flavor	string	Flavor overrid. Valid value is FilePos.
--db_host	string	The host name for the tcp connection.
--db_port	int	tcp port
--db_repl_password	string	db repl password
--db_repl_use_ssl		Set this flag to false to make the repl connection to not use SSL (default true)
--db_repl_user	string	db repl user userKey (default "vt_repl")
--db_server_name	string	server name of the DB we are connecting to.
--db_socket	string	The unix socket to connect on. If this is specified, host and port will not be used.
--db_ssl_ca	string	connection SSL ca
--db_ssl_ca_path	string	connection SSL ca path
--db_ssl_cert	string	connection SSL certificate
--db_ssl_key	string	connection SSL key
--db_tls_min_version	string	Configures the minimal TLS version negotiated when SSL is enabled. Defaults to TLSv1.2. Options: TLSv1.0, TLSv1.1, TLSv1.2, TLSv1.3
--dba_idle_timeout	duration	Idle timeout for dba connections (default 1m0s)
--dba_pool_size	int	Size of the connection pool for dba connections (default 20)
--degraded_threshold	duration	replication lag after which a replica is considered degraded (only used in status UI) (default 30s)
--disable_active_reparents		if set, do not allow active reparents. Use this to protect a cluster using external reparents.
--discovery_high_replication_lag_minimum_serving	duration	the replication lag that is considered too high when selecting the minimum num vttablets for serving (default 2h0m0s)
--discovery_low_replication_lag	duration	the replication lag that is considered low enough to be healthy (default 30s)
--emit_stats		true iff we should emit stats to push-based monitoring/stats backends
--enable-consolidator		This option enables the query consolidator. (default true)
--enable-consolidator-replicas		This option enables the query consolidator only on replicas.
--enable-query-plan-field-caching		This option fetches & caches fields (columns) when storing query plans (default true)
--enable-tx-throttler		If true replication-lag-based throttling on transactions will be enabled.
--enable_hot_row_protection		If true, incoming transactions for the same row (range) will be queued and cannot consume all txpool slots.
--enable_hot_row_protection_dry_run		If true, hot row protection is not enforced but logs if transactions would have been queued.
--enable_replication_reporter		Register the health check module that monitors MySQL replication
--enable_semi_sync		DEPRECATED - Set the correct durability policy in the keyspace information instead
--enable_transaction_limit		If true, limit on number of transactions open at the same time will be enforced for all users. User trying to open a new transaction after exhausting their limit will receive an error immediately, regardless of whether there are available slots or not.
--enable_transaction_limit_dry_run		If true, limit on number of transactions open at the same time will be tracked for all users, but not enforced.
--enforce-tableacl-config		if this flag is true, vttablet will fail to start if a valid tableacl config does not exist
--enforce_strict_trans_tables		If true, vttablet requires MySQL to run with STRICT_TRANS_TABLES or STRICT_ALL_TABLES on. It is recommended to not turn this flag off. Otherwise MySQL may alter your supplied values before saving them to the database. (default true)
--file_backup_storage_root	string	root directory for the file backup storage -- this path must be on shared storage to provide a global view of backups to all vitess components
--filecustomrules	string	file based custom rule path
--finalize_external_reparent_timeout	duration	Timeout for the finalize stage of a fast external reparent reconciliation. (default 30s)
--gcs_backup_storage_bucket	string	Google Cloud Storage bucket to use for backups
--gcs_backup_storage_root	string	root prefix for all backup-related object names
--grpc_auth_mode	string	Which auth plugin implementation to use (eg: static)
--grpc_auth_mtls_allowed_substrings	string	List of substrings of at least one of the client certificate names (separated by colon).
--grpc_auth_static_client_creds	string	when using grpc_static_auth in the server, this file provides the credentials to use to authenticate with server
--grpc_auth_static_password_file	string	JSON File to read the users/passwords from.
--grpc_ca	string	ca to use, requires TLS, and enforces client cert check
--grpc_cert	string	certificate to use, requires grpc_key, enables TLS
--grpc_compression	string	how to compress gRPC, default: nothing, supported: snappy
--grpc_enable_tracing		Enable GRPC tracing
--grpc_initial_conn_window_size	int	grpc initial connection window size
--grpc_initial_window_size	int	grpc initial window size
--grpc_keepalive_time	duration	After a duration of this time if the client doesn't see any activity it pings the server to see if the transport is still alive. (default 10s)
--grpc_keepalive_timeout	duration	After having pinged for keepalive check, the client waits for a duration of Timeout and if no activity is seen even after that the connection is closed. (default 10s)
--grpc_key	string	key to use, requires grpc_cert, enables TLS
--grpc_max_connection_age	duration	Maximum age of a client connection before GoAway is sent. (default 2562047h47m16.854775807s)
--grpc_max_connection_age_grace	duration	Additional grace period after grpc_max_connection_age, after which connections are forcibly closed. (default 2562047h47m16.854775807s)
--grpc_max_message_size	int	Maximum allowed RPC message size. Larger messages will be rejected by gRPC with the error 'exceeding the max size'. (default 16777216)
--grpc_port	int	Port to listen on for gRPC calls
--grpc_prometheus		Enable gRPC monitoring with Prometheus
--grpc_server_initial_conn_window_size	int	grpc server initial connection window size
--grpc_server_initial_window_size	int	grpc server initial window size
--grpc_server_keepalive_enforcement_policy_min_time	duration	grpc server minimum keepalive time (default 5m0s)
--grpc_server_keepalive_enforcement_policy_permit_without_stream		grpc server permit client keepalive pings even when there are no active streams (RPCs)
--health_check_interval	duration	Interval between health checks (default 20s)
--heartbeat_enable		If true, vttablet records (if primary) or checks (if replica) the current time of a replication heartbeat in the table _vt.heartbeat. The result is used to inform the serving state of the vttablet via healthchecks.
--heartbeat_interval	duration	How frequently to read and write replication heartbeat. (default 1s)
--hot_row_protection_concurrent_transactions	int	Number of concurrent transactions let through to the txpool/MySQL for the same hot row. Should be > 1 to have enough 'ready' transactions in MySQL and benefit from a pipelining effect. (default 5)
--hot_row_protection_max_global_queue_size	int	Global queue limit across all row (ranges). Useful to prevent that the queue can grow unbounded. (default 1000)
--hot_row_protection_max_queue_size	int	Maximum number of BeginExecute RPCs which will be queued for the same row (range). (default 20)
--init_db_name_override	string	(init parameter) override the name of the db used by vttablet. Without this flag, the db name defaults to vt_
--init_keyspace	string	(init parameter) keyspace to use for this tablet
--init_populate_metadata		(init parameter) populate metadata tables even if restore_from_backup is disabled. If restore_from_backup is enabled, metadata tables are always populated regardless of this flag.
--init_shard	string	(init parameter) shard to use for this tablet
--init_tablet_type	string	(init parameter) the tablet type to use for this tablet.
--init_tags	value	(init parameter) comma separated list of key:value pairs used to tag the tablet
--init_timeout	duration	(init parameter) timeout to use for the init phase. (default 1m0s)
--jaeger-agent-host	string	host and port to send spans to. If empty, no tracing will be done
--keep_logs	duration	keep logs for this long (using ctime) (zero to keep forever). Note ctime here means "change time" and can be essentially equivalent to mtime. Read #5318
--keep_logs_by_mtime	duration	keep logs for this long (using mtime) (zero to keep forever)
--lameduck-period	duration	keep running at least this long after SIGTERM before stopping (default 50ms)
--legacy_replication_lag_algorithm		use the legacy algorithm when selecting the vttablets for serving (default true)
--lock_tables_timeout	duration	How long to keep the table locked before timing out (default 1m0s)
--log_backtrace_at	value	when logging hits line file:N, emit a stack trace
--log_dir	string	If non-empty, write log files in this directory
--log_err_stacks		log stack traces for errors
--log_queries		Enable query logging to syslog.
--log_queries_to_file	string	Enable query logging to the specified file
--log_rotate_max_size	uint	size in bytes at which logs are rotated (glog.MaxSize) (default 1887436800)
--logtostderr		log to standard error instead of files
--replication_connect_retry	duration	how long to wait in between replica reconnect attempts. Only precise to the second. (default 10s)
--mem-profile-rate	int	profile every n bytes allocated (default 524288)
--min_number_serving_vttablets	int	the minimum number of vttablets that will be continue to be used even with low replication lag (default 2)
--mutex-profile-fraction	int	profile every n mutex contention events (see runtime.SetMutexProfileFraction)
--mycnf-file	string	path to my.cnf, if reading all config params from there
--mycnf_bin_log_path	string	mysql binlog path
--mycnf_data_dir	string	data directory for mysql
--mycnf_error_log_path	string	mysql error log path
--mycnf_general_log_path	string	mysql general log path
--mycnf_innodb_data_home_dir	string	Innodb data home directory
--mycnf_innodb_log_group_home_dir	string	Innodb log group home directory
--mycnf_master_info_file	string	mysql master.info file
--mycnf_mysql_port	int	port mysql is listening on
--mycnf_pid_file	string	mysql pid file
--mycnf_relay_log_index_path	string	mysql relay log index path
--mycnf_relay_log_info_path	string	mysql relay log info path
--mycnf_relay_log_path	string	mysql relay log path
--mycnf_server_id	int	mysql server id of the server (if specified, mycnf-file will be ignored)
--mycnf_slow_log_path	string	mysql slow query log path
--mycnf_socket_file	string	mysql socket file
--mycnf_tmp_dir	string	mysql tmp directory
--mysql_auth_server_static_file	string	JSON File to read the users/passwords from.
--mysql_auth_server_static_string	string	JSON representation of the users/passwords config.
--mysql_auth_static_reload_interval	duration	Ticker to reload credentials
--mysql_clientcert_auth_method	string	client-side authentication method to use. Supported values: mysql_clear_password, dialog. (default "mysql_clear_password")
--mysql_server_flush_delay	duration	Delay after which buffered response will flushed to client. (default 100ms)
--mysql_server_version	string	MySQL server version to advertise.
--mysqlctl_client_protocol	string	the protocol to use to talk to the mysqlctl server (default "grpc")
--mysqlctl_mycnf_template	string	template file to use for generating the my.cnf file during server init
--mysqlctl_socket	string	socket file to use for remote mysqlctl actions (empty for local actions)
--onterm_timeout	duration	wait no more than this for OnTermSync handlers before stopping (default 10s)
--opentsdb_uri	string	URI of opentsdb /api/put method
--orc_api_password	string	(Optional) Basic auth password to authenticate with Orchestrator's HTTP API.
--orc_api_url	string	Address of Orchestrator's HTTP API (e.g. http://host:port/api/). Leave empty to disable Orchestrator integration.
--orc_api_user	string	(Optional) Basic auth username to authenticate with Orchestrator's HTTP API. Leave empty to disable basic auth.
--orc_discover_interval	duration	How often to ping Orchestrator's HTTP API endpoint to tell it we exist. 0 means never.
--orc_timeout	duration	Timeout for calls to Orchestrator's HTTP API (default 30s)
--pid_file	string	If set, the process will write its pid to the named file, and delete it on graceful shutdown.
--pool_hostname_resolve_interval	duration	if set force an update to all hostnames and reconnect if changed, defaults to 0 (disabled)
--port	int	port for the server
--purge_logs_interval	duration	how often try to remove old logs (default 1h0m0s)
--query-log-stream-handler	string	URL handler for streaming queries log (default "/debug/querylog")
--querylog-filter-tag	string	string that must be present in the query as a comment for the query to be logged, works for both vtgate and vttablet
--querylog-format	string	format for query logs ("text" or "json") (default "text")
--queryserver-config-acl-exempt-acl	string	an acl that exempt from table acl checking (this acl is free to access any vitess tables).
--queryserver-config-enable-table-acl-dry-run		If this flag is enabled, tabletserver will emit monitoring metrics and let the request pass regardless of table acl check results
--queryserver-config-idle-timeout	int	query server idle timeout (in seconds), vttablet manages various mysql connection pools. This config means if a connection has not been used in given idle timeout, this connection will be removed from pool. This effectively manages number of connection objects and optimize the pool performance. (default 1800)
--queryserver-config-max-result-size	int	query server max result size, maximum number of rows allowed to return from vttablet for non-streaming queries. (default 10000)
--queryserver-config-message-postpone-cap	int	query server message postpone cap is the maximum number of messages that can be postponed at any given time. Set this number to substantially lower than transaction cap, so that the transaction pool isn't exhausted by the message subsystem. (default 4)
--queryserver-config-passthrough-dmls		query server pass through all dml statements without rewriting
--queryserver-config-pool-prefill-parallelism	int	query server read pool prefill parallelism, a non-zero value will prefill the pool using the specified parallism.
--queryserver-config-pool-size	int	query server read pool size, connection pool is used by regular queries (non streaming, not in a transaction) (default 16)
--queryserver-config-query-cache-size	int	query server query cache size, maximum number of queries to be cached. vttablet analyzes every incoming query and generate a query plan, these plans are being cached in a lru cache. This config controls the capacity of the lru cache. (default 5000)
--queryserver-config-query-pool-timeout	int	query server query pool timeout (in seconds), it is how long vttablet waits for a connection from the query pool. If set to 0 (default) then the overall query timeout is used instead.
--queryserver-config-query-pool-waiter-cap	int	query server query pool waiter limit, this is the maximum number of queries that can be queued waiting to get a connection (default 5000)
--queryserver-config-query-timeout	int	query server query timeout (in seconds), this is the query timeout in vttablet side. If a query takes more than this timeout, it will be killed. (default 30)
--queryserver-config-schema-reload-time	int	query server schema reload time, how often vttablet reloads schemas from underlying MySQL instance in seconds. vttablet keeps table schemas in its own memory and periodically refreshes it from MySQL. This config controls the reload time. (default 1800)
--queryserver-config-schema-change-signal-interval	int	interval used to periodically send schema change updates to vtgate (default 5 seconds)
--queryserver-config-schema-change-signal	boolean	enable schema tracking
--queryserver-config-stream-buffer-size	int	query server stream buffer size, the maximum number of bytes sent from vttablet for each stream call. It's recommended to keep this value in sync with vtgate's stream_buffer_size. (default 32768)
--queryserver-config-stream-pool-prefill-parallelism	int	query server stream pool prefill parallelism, a non-zero value will prefill the pool using the specified parallelism
--queryserver-config-stream-pool-size	int	query server stream connection pool size, stream pool is used by stream queries: queries that return results to client in a streaming fashion (default 200)
--queryserver-config-stream-pool-waiter-cap	int	query server stream pool waiter limit, this is the maximum number of streaming queries that can be queued waiting to get a connection (default unlimited)
--queryserver-config-strict-table-acl		only allow queries that pass table acl checks
--queryserver-config-terse-errors		prevent bind vars from escaping in client error messages
--queryserver-config-transaction-cap	int	query server transaction cap is the maximum number of transactions allowed to happen at any given point of a time for a single vttablet. E.g. by setting transaction cap to 100, there are at most 100 transactions will be processed by a vttablet and the 101th transaction will be blocked (and fail if it cannot get connection within specified timeout) (default 20)
--queryserver-config-transaction-prefill-parallelism	int	query server transaction prefill parallelism, a non-zero value will prefill the pool using the specified parallism.
--queryserver-config-transaction-timeout	int	query server transaction timeout (in seconds), a transaction will be killed if it takes longer than this value (default 30)
--queryserver-config-txpool-timeout	int	query server transaction pool timeout, it is how long vttablet waits if tx pool is full (default 1)
--queryserver-config-txpool-waiter-cap	int	query server transaction pool waiter limit, this is the maximum number of transactions that can be queued waiting to get a connection (default 5000)
--queryserver-config-warn-result-size	int	query server result size warning threshold, warn if number of rows returned from vttablet for non-streaming queries exceeds this
--redact-debug-ui-queries		redact full queries and bind variables from debug UI
--remote_operation_timeout	duration	time to wait for a remote operation (default 30s)
--restore_concurrency	int	(init restore parameter) how many concurrent files to restore at once (default 4)
--restore_from_backup		(init restore parameter) will check BackupStorage for a recent backup at startup and start there
--restore_from_backup_ts	string	(init restore parameter) if set, restore the latest backup taken at or before this timestamp. Example: '2021-04-29.133050' (Vitess 12.0+)
--s3_backup_aws_endpoint	string	endpoint of the S3 backend (region must be provided)
--s3_backup_aws_region	string	AWS region to use (default "us-east-1")
--s3_backup_aws_retries	int	AWS request retries (default -1)
--s3_backup_force_path_style		force the s3 path style
--s3_backup_log_level	string	determine the S3 loglevel to use from LogOff, LogDebug, LogDebugWithSigning, LogDebugWithHTTPBody, LogDebugWithRequestRetries, LogDebugWithRequestErrors (default "LogOff")
--s3_backup_server_side_encryption	string	server-side encryption algorithm (e.g., AES256, aws:kms)
--s3_backup_storage_bucket	string	S3 bucket to use for backups
--s3_backup_storage_root	string	root prefix for all backup-related object names
--s3_backup_tls_skip_verify_cert		skip the 'certificate is valid' check for SSL connections
--sanitize_log_messages	bool	Remove potentially sensitive information in tablet INFO, WARNING, and ERROR log messages such as query parameters
--security_policy	string	the name of a registered security policy to use for controlling access to URLs - empty means allow all for anyone (built-in policies: deny-all, read-only)
--service_map	value	comma separated list of services to enable (or disable if prefixed with '-') Example: grpc-queryservice
--serving_state_grace_period	duration	how long to pause after broadcasting health to vtgate, before enforcing a new serving state
--shard_sync_retry_delay	duration	delay between retries of updates to keep the tablet and its shard record in sync (default 30s)
--sql-max-length-errors	int	truncate queries in error logs to the given length (default unlimited)
--sql-max-length-ui	int	truncate queries in debug UIs to the given length (default 512) (default 512)
--srv_topo_cache_refresh	duration	how frequently to refresh the topology for cached entries (default 1s)
--srv_topo_cache_ttl	duration	how long to use cached entries for topology (default 1s)
--stats_backend	string	The name of the registered push-based monitoring/stats backend to use
--stats_combine_dimensions	string	List of dimensions to be combined into a single "all" value in exported stats vars
--stats_drop_variables	string	Variables to be dropped from the list of exported variables.
--stats_emit_period	duration	Interval between emitting stats to all registered backends (default 1m0s)
--stderrthreshold	value	logs at or above this threshold go to stderr (default 1)
--table-acl-config	string	path to table access checker config file; send SIGHUP to reload this file
--table-acl-config-reload-interval	duration	Ticker to reload ACLs
--tablet-path	string	tablet alias
--tablet_config	string	YAML file config for tablet
--tablet_dir	string	The directory within the vtdataroot to store vttablet/mysql files. Defaults to being generated by the tablet uid.
--tablet_grpc_ca	string	the server ca to use to validate servers when connecting
--tablet_grpc_cert	string	the cert to use to connect
--tablet_grpc_key	string	the key to use to connect
--tablet_grpc_server_name	string	the server name to use to validate server certificate
--tablet_hostname	string	if not empty, this hostname will be assumed instead of trying to resolve it
--tablet_manager_grpc_ca	string	the server ca to use to validate servers when connecting
--tablet_manager_grpc_cert	string	the cert to use to connect
--tablet_manager_grpc_concurrency	int	concurrency to use to talk to a vttablet server for performance-sensitive RPCs (like ExecuteFetchAs{Dba,AllPrivs,App}) (default 8)
--tablet_manager_grpc_key	string	the key to use to connect
--tablet_manager_grpc_server_name	string	the server name to use to validate server certificate
--tablet_manager_protocol	string	the protocol to use to talk to vttablet (default "grpc")
--tablet_protocol	string	how to talk to the vttablets (default "grpc")
--tablet_url_template	string	format string describing debug tablet url formatting. See the Go code for getTabletDebugURL() how to customize this. (default "http://{{.GetTabletHostPort}}")
--topo_consul_watch_poll_duration	duration	time of the long poll for watch queries. (default 30s)
--topo_etcd_lease_ttl	int	Lease TTL for locks and leader election. The client will use KeepAlive to keep the lease going. (default 30)
--topo_etcd_tls_ca	string	path to the ca to use to validate the server cert when connecting to the etcd topo server
--topo_etcd_tls_cert	string	path to the client cert to use to connect to the etcd topo server, requires topo_etcd_tls_key, enables TLS
--topo_etcd_tls_key	string	path to the client key to use to connect to the etcd topo server, enables TLS
--topo_global_root	string	the path of the global topology data in the global topology server
--topo_global_server_address	string	the address of the global topology server
--topo_implementation	string	the topology implementation to use
--topo_k8s_context	string	The kubeconfig context to use, overrides the 'current-context' from the config
--topo_k8s_kubeconfig	string	Path to a valid kubeconfig file.
--topo_k8s_namespace	string	The kubernetes namespace to use for all objects. Default comes from the context or in-cluster config
--topo_zk_auth_file	string	auth to use when connecting to the zk topo server, file contents should be :, e.g., digest:user:pass
--topo_zk_base_timeout	duration	zk base timeout (see zk.Connect) (default 30s)
--topo_zk_max_concurrency	int	maximum number of pending requests to send to a Zookeeper server. (default 64)
--topo_zk_tls_ca	string	the server ca to use to validate servers when connecting to the zk topo server
--topo_zk_tls_cert	string	the cert to use to connect to the zk topo server, requires topo_zk_tls_key, enables TLS
--topo_zk_tls_key	string	the key to use to connect to the zk topo server, enables TLS
--topocustomrule_cell	string	topo cell for customrules file. (default "global")
--topocustomrule_path	string	path for customrules file. Disabled if empty.
--tracer	string	tracing service to use (default "noop")
--tracing-sampling-rate	float	sampling rate for the probabilistic jaeger sampler (default 0.1)
--transaction-log-stream-handler	string	URL handler for streaming transactions log (default "/debug/txlog")
--transaction_limit_by_component		Include CallerID.component when considering who the user is for the purpose of transaction limit.
--transaction_limit_by_principal		Include CallerID.principal when considering who the user is for the purpose of transaction limit. (default true)
--transaction_limit_by_subcomponent		Include CallerID.subcomponent when considering who the user is for the purpose of transaction limit.
--transaction_limit_by_username		Include VTGateCallerID.username when considering who the user is for the purpose of transaction limit. (default true)
--transaction_limit_per_user	float	Maximum number of transactions a single user is allowed to use at any time, represented as fraction of --transaction_cap. (default 0.4)
--shutdown_grace_period	float	how long to wait (in seconds) for queries and transactions to complete during graceful shutdown.
--twopc_abandon_age	float	time in seconds. Any unresolved transaction older than this time will be sent to the coordinator to be resolved.
--twopc_coordinator_address	string	address of the (VTGate) process(es) that will be used to notify of abandoned transactions.
--twopc_enable		if the flag is on, 2pc is enabled. Other 2pc flags must be supplied.
--tx-throttler-config	string	The configuration of the transaction throttler as a text formatted throttlerdata.Configuration protocol buffer message (default "target_replication_lag_sec: 2 max_replication_lag_sec: 10 initial_rate: 100 max_increase: 1 emergency_decrease: 0.5 min_duration_between_increases_sec: 40 max_duration_between_increases_sec: 62 min_duration_between_decreases_sec: 20 spread_backlog_across_sec: 20 age_bad_rate_after_sec: 180 bad_rate_increase: 0.1 max_rate_approach_threshold: 0.9 ")
--tx-throttler-healthcheck-cells	value	A comma-separated list of cells. Only tabletservers running in these cells will be monitored for replication lag by the transaction throttler.
--unhealthy_threshold	duration	replication lag after which a replica is considered unhealthy (default 2h0m0s)
--use_super_read_only		Set super_read_only flag when performing planned failover.
-v	value	log level for V logs
--version		print binary version
--vmodule	value	comma-separated list of pattern=N settings for file-filtered logging
--vreplication_copy_phase_max_innodb_history_list_length	int	The maximum InnoDB transaction history that can exist on a vstreamer (source) before starting another round of copying rows. This helps to limit the impact on the source tablet. (default 1000000)
--vreplication_copy_phase_max_mysql_replication_lag	int	The maximum MySQL replication lag (in seconds) that can exist on a vstreamer (source) before starting another round of copying rows. This helps to limit the impact on the source tablet. (default 43200)
--vreplication_healthcheck_retry_delay	duration	healthcheck retry delay (default 5s)
--vreplication_healthcheck_timeout	duration	healthcheck retry delay (default 1m0s)
--vreplication_healthcheck_topology_refresh	duration	refresh interval for re-reading the topology (default 30s)
--vreplication_retry_delay	duration	delay before retrying a failed binlog connection (default 5s)
--vreplication_tablet_type	string	comma separated list of tablet types used as a source (default "in_order:REPLICA,PRIMARY")
--vstream_packet_size	int	Suggested packet size for VReplication streamer. This is used only as a recommendation. The actual packet size may be more or less than this amount. (default 30000)
--vtctld_addr	string	address of a vtctld instance
--vtgate_protocol	string	how to talk to vtgate (default "grpc")
--wait_for_backup_interval	duration	(init restore parameter) if this is greater than 0, instead of starting up empty when no backups are found, keep checking at this interval for a backup to appear
--watch_replication_stream		When enabled, vttablet will stream the MySQL replication stream from the local server, and use it to support the include_event_token ExecuteOptions.
--xbstream_restore_flags	string	flags to pass to xbstream command during restore. These should be space separated and will be added to the end of the command. These need to match the ones used for backup e.g. --compress / --decompress, --encrypt / --decrypt
--xtrabackup_backup_flags	string	flags to pass to backup command. These should be space separated and will be added to the end of the command
--xtrabackup_prepare_flags	string	flags to pass to prepare command. These should be space separated and will be added to the end of the command
--xtrabackup_root_path	string	directory location of the xtrabackup executable, e.g., /usr/bin
--xtrabackup_stream_mode	string	which mode to use if streaming, valid values are tar and xbstream (default "tar")
--xtrabackup_stripe_block_size	uint	Size in bytes of each block that gets sent to a given stripe before rotating to the next stripe (default 102400)
--xtrabackup_stripes	uint	If greater than 0, use data striping across this many destination files to parallelize data transfer and decompression
--xtrabackup_user	string	User that xtrabackup will use to connect to the database server. This user must have all necessary privileges. For details, please refer to xtrabackup documentation.

Key Options

• --restore_from_backup: The default value for this flag is false. If set to true, and the my.cnf file was successfully loaded, then vttablet can perform automatic restores as follows:

  • If started against a mysql instance that has no data files, it will search the list of backups for the latest one, and initiate a restore. After this, it will point the mysql to the current primary and wait for replication to catch up. Once replication is caught up to the specified tolerance limit, it will advertise itself as serving. This will cause the vtgates to add it to the list of healthy tablets to serve queries from.
  • If this flag is true, but my.cnf was not loaded, then vttablet will fatally exit with an error message.
  • You can additionally control the level of concurrency for a restore with the --restore_concurrency flag. This is typically useful in cloud environments to prevent the restore process from becoming a 'noisy' neighbor by consuming all available disk IOPS.