vtgate

VTGate is a stateless proxy responsible for accepting requests from applications and routing them to the appropriate tablet server(s) for query execution. It speaks both the MySQL Protocol and a gRPC protocol.

Example Usage

Start a vtgate proxy:

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

vtgate \
  $TOPOLOGY_FLAGS \
  -log_dir $VTDATAROOT/tmp \
  -port 15001 \
  -grpc_port 15991 \
  -mysql_server_port 15306 \
  -cell test \
  -cells_to_watch test \
  -tablet_types_to_wait MASTER,REPLICA \
  -gateway_implementation discoverygateway \
  -service_map 'grpc-vtgateservice' \
  -pid_file $VTDATAROOT/tmp/vtgate.pid \
  -mysql_auth_server_impl none

Options

The following global options apply to vtgate:

NameTypeDefinition
-allowed_tablet_typesvalueSpecifies the tablet types this vtgate is allowed to route queries to
-alsologtostderrbooleanlog to standard error as well as files
-buffer_drain_concurrencyintMaximum number of requests retried simultaneously. More concurrency will increase the load on the MASTER vttablet when draining the buffer. (default 1)
-buffer_keyspace_shardsstringIf not empty, limit buffering to these entries (comma separated). Entry format: keyspace or keyspace/shard. Requires –enable_buffer=true.
-buffer_max_failover_durationdurationStop buffering completely if a failover takes longer than this duration. (default 20s)
-buffer_min_time_between_failoversdurationMinimum time between the end of a failover and the start of the next one (tracked per shard). Faster consecutive failovers will not trigger buffering. (default 1m0s)
-buffer_sizeintMaximum number of buffered requests in flight (across all ongoing failovers). (default 10)
-buffer_windowdurationDuration for how long a request should be buffered at most. (default 10s)
-cellstringcell to use (default “test_nj”)
-cells_to_watchstringcomma-separated list of cells for watching tablets
-consul_auth_static_filestringJSON File to read the topos/tokens from.
-cpu_profilestringwrite cpu profile to file
-datadog-agent-hoststringhost to send spans to. if empty, no tracing will be done
-datadog-agent-portstringport to send spans to. if empty, no tracing will be done
-default_tablet_typevalueThe default tablet type to set for queries, when one is not explicitly selected (default MASTER)
-discovery_high_replication_lag_minimum_servingdurationthe replication lag that is considered too high when selecting the minimum num vttablets for serving (default 2h0m0s)
-discovery_low_replication_lagdurationthe replication lag that is considered low enough to be healthy (default 30s)
-emit_statsbooleantrue iff we should emit stats to push-based monitoring/stats backends
-enable_bufferbooleanEnable buffering (stalling) of master traffic during failovers.
-enable_buffer_dry_runbooleanDetect and log failover events, but do not actually buffer requests.
-gate_query_cache_sizeintgate server query cache size, maximum number of queries to be cached. vtgate 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 10000)
-gateway_implementationstringThe implementation of gateway (default “discoverygateway”)
-gateway_initial_tablet_timeoutdurationAt startup, the gateway will wait up to that duration to get one tablet per keyspace/shard/tablettype (default 30s)
-grpc_auth_modestringWhich auth plugin implementation to use (eg: static)
-grpc_auth_mtls_allowed_substringsstringList of substrings of at least one of the client certificate names (separated by colon).
-grpc_auth_static_client_credsstringwhen using grpc_static_auth in the server, this file provides the credentials to use to authenticate with server
-grpc_auth_static_password_filestringJSON File to read the users/passwords from.
-grpc_castringca to use, requires TLS, and enforces client cert check
-grpc_certstringcertificate to use, requires grpc_key, enables TLS
-grpc_compressionstringhow to compress gRPC, default: nothing, supported: snappy
-grpc_enable_tracingbooleanEnable GRPC tracing
-grpc_initial_conn_window_sizeintgrpc initial connection window size
-grpc_initial_window_sizeintgrpc initial window size
-grpc_keepalive_timedurationAfter 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_timeoutdurationAfter 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_keystringkey to use, requires grpc_cert, enables TLS
-grpc_max_connection_agedurationMaximum age of a client connection before GoAway is sent. (default 2562047h47m16.854775807s)
-grpc_max_connection_age_gracedurationAdditional grace period after grpc_max_connection_age, after which connections are forcibly closed. (default 2562047h47m16.854775807s)
-grpc_max_message_sizeintMaximum allowed RPC message size. Larger messages will be rejected by gRPC with the error ‘exceeding the max size’. (default 16777216)
-grpc_portintPort to listen on for gRPC calls
-grpc_prometheusbooleanEnable gRPC monitoring with Prometheus
-grpc_server_initial_conn_window_sizeintgrpc server initial connection window size
-grpc_server_initial_window_sizeintgrpc server initial window size
-grpc_server_keepalive_enforcement_policy_min_timedurationgrpc server minimum keepalive time (default 5m0s)
-grpc_server_keepalive_enforcement_policy_permit_without_streambooleangrpc server permit client keepalive pings even when there are no active streams (RPCs)
-grpc_use_effective_calleridbooleanIf set, and SSL is not used, will set the immediate caller id from the effective caller id’s principal.
-healthcheck_retry_delaydurationhealth check retry delay (default 2ms)
-healthcheck_timeoutdurationthe health check timeout period (default 1m0s)
-jaeger-agent-hoststringhost and port to send spans to. if empty, no tracing will be done
-keep_logsdurationkeep logs for this long (using ctime) (zero to keep forever)
-keep_logs_by_mtimedurationkeep logs for this long (using mtime) (zero to keep forever)
-keyspaces_to_watchvalueSpecifies which keyspaces this vtgate should have access to while routing queries or accessing the vschema
-lameduck-perioddurationkeep running at least this long after SIGTERM before stopping (default 50ms)
-legacy_replication_lag_algorithmbooleanuse the legacy algorithm when selecting the vttablets for serving (default true)
-log_backtrace_atvaluewhen logging hits line file:N, emit a stack trace
-log_dirstringIf non-empty, write log files in this directory
-log_err_stacksbooleanlog stack traces for errors
-log_queries_to_filestringEnable query logging to the specified file
-log_rotate_max_sizeuintsize in bytes at which logs are rotated (glog.MaxSize) (default 1887436800)
-logtostderrbooleanlog to standard error instead of files
-max_memory_rowsintMaximum number of rows that will be held in memory for intermediate results as well as the final result. (default 300000)
-mem-profile-rateintprofile every n bytes allocated (default 524288)
-message_stream_grace_perioddurationthe amount of time to give for a vttablet to resume if it ends a message stream, usually because of a reparent. (default 30s)
-min_number_serving_vttabletsintthe minimum number of vttablets that will be continue to be used even with low replication lag (default 2)
-mutex-profile-fractionintprofile every n mutex contention events (see runtime.SetMutexProfileFraction)
-mysql_allow_clear_text_without_tlsbooleanIf set, the server will allow the use of a clear text password over non-SSL connections.
-mysql_auth_server_implstringWhich auth server implementation to use. (default “static”)
-mysql_auth_server_static_filestringJSON File to read the users/passwords from.
-mysql_auth_server_static_stringstringJSON representation of the users/passwords config.
-mysql_auth_static_reload_intervaldurationTicker to reload credentials
-mysql_clientcert_auth_methodstringclient-side authentication method to use. Supported values: mysql_clear_password, dialog. (default “mysql_clear_password”)
-mysql_default_workloadstringDefault session workload (OLTP, OLAP, DBA) (default “UNSPECIFIED”)
-mysql_ldap_auth_config_filestringJSON File from which to read LDAP server config.
-mysql_ldap_auth_config_stringstringJSON representation of LDAP server config.
-mysql_ldap_auth_methodstringclient-side authentication method to use. Supported values: mysql_clear_password, dialog. (default “mysql_clear_password”)
-mysql_server_bind_addressstringBinds on this address when listening to MySQL binary protocol. Useful to restrict listening to ‘localhost’ only for instance.
-mysql_server_flush_delaydurationDelay after which buffered response will flushed to client. (default 100ms)
-mysql_server_portintIf set, also listen for MySQL binary protocol connections on this port. (default -1)
-mysql_server_query_timeoutdurationmysql query timeout
-mysql_server_read_timeoutdurationconnection read timeout
-mysql_server_require_secure_transportbooleanReject insecure connections but only if mysql_server_ssl_cert and mysql_server_ssl_key are provided
-mysql_server_socket_pathstringThis option specifies the Unix socket file to use when listening for local connections. By default it will be empty and it won’t listen to a unix socket
-mysql_server_ssl_castringPath to ssl CA for mysql server plugin SSL. If specified, server will require and validate client certs.
-mysql_server_ssl_certstringPath to the ssl cert for mysql server plugin SSL
-mysql_server_ssl_keystringPath to ssl key for mysql server plugin SSL
-mysql_server_versionstringMySQL server version to advertise. (default “5.7.9-Vitess”)
-mysql_server_write_timeoutdurationconnection write timeout
-mysql_slow_connect_warn_thresholddurationWarn if it takes more than the given threshold for a mysql connection to establish
-mysql_tcp_versionstringSelect tcp, tcp4, or tcp6 to control the socket type. (default “tcp”)
-normalize_queriesbooleanRewrite queries with bind vars. Turn this off if the app itself sends normalized queries with bind vars. (default true)
-onterm_timeoutdurationwait no more than this for OnTermSync handlers before stopping (default 10s)
-opentsdb_uristringURI of opentsdb /api/put method
-pid_filestringIf set, the process will write its pid to the named file, and delete it on graceful shutdown.
-portintport for the server
-proxy_protocolbooleanEnable HAProxy PROXY protocol on MySQL listener socket
-purge_logs_intervaldurationhow often try to remove old logs (default 1h0m0s)
-querylog-filter-tagstringstring that must be present in the query as a comment for the query to be logged, works for both vtgate and vttablet
-querylog-formatstringformat for query logs (“text” or “json”) (default “text”)
-redact-debug-ui-queriesbooleanredact full queries and bind variables from debug UI
-remote_operation_timeoutdurationtime to wait for a remote operation (default 30s)
-retry-countintretry count (default 2)
-security_policystringthe 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_mapvaluecomma separated list of services to enable (or disable if prefixed with ‘-') Example: grpc-vtworker
-sql-max-length-errorsinttruncate queries in error logs to the given length (default unlimited)
-sql-max-length-uiinttruncate queries in debug UIs to the given length (default 512) (default 512)
-srv_topo_cache_refreshdurationhow frequently to refresh the topology for cached entries (default 1s)
-srv_topo_cache_ttldurationhow long to use cached entries for topology (default 1s)
-stats_backendstringThe name of the registered push-based monitoring/stats backend to use
-stats_combine_dimensionsstringList of dimensions to be combined into a single “all” value in exported stats vars
-stats_drop_variablesstringVariables to be dropped from the list of exported variables.
-stats_emit_perioddurationInterval between emitting stats to all registered backends (default 1m0s)
-stderrthresholdvaluelogs at or above this threshold go to stderr (default 1)
-stream_buffer_sizeintthe number of bytes sent from vtgate for each stream call. It’s recommended to keep this value in sync with vttablet’s query-server-config-stream-buffer-size. (default 32768)
-tablet_filtersvalueSpecifies a comma-separated list of ‘keyspace
-tablet_grpc_castringthe server ca to use to validate servers when connecting
-tablet_grpc_certstringthe cert to use to connect
-tablet_grpc_keystringthe key to use to connect
-tablet_grpc_server_namestringthe server name to use to validate server certificate
-tablet_protocolstringhow to talk to the vttablets (default “grpc”)
-tablet_refresh_intervaldurationtablet refresh interval (default 1m0s)
-tablet_refresh_known_tabletsbooleantablet refresh reloads the tablet address/port map from topo in case it changes (default true)
-tablet_types_to_waitstringwait till connected for specified tablet types during Gateway initialization
-tablet_url_templatestringformat string describing debug tablet url formatting. See the Go code for getTabletDebugURL() how to customize this. (default “http://{{.GetTabletHostPort}}")
-topo_consul_watch_poll_durationdurationtime of the long poll for watch queries. (default 30s)
-topo_etcd_lease_ttlintLease TTL for locks and master election. The client will use KeepAlive to keep the lease going. (default 30)
-topo_etcd_tls_castringpath to the ca to use to validate the server cert when connecting to the etcd topo server
-topo_etcd_tls_certstringpath to the client cert to use to connect to the etcd topo server, requires topo_etcd_tls_key, enables TLS
-topo_etcd_tls_keystringpath to the client key to use to connect to the etcd topo server, enables TLS
-topo_global_rootstringthe path of the global topology data in the global topology server
-topo_global_server_addressstringthe address of the global topology server
-topo_implementationstringthe topology implementation to use
-topo_k8s_contextstringThe kubeconfig context to use, overrides the ‘current-context’ from the config
-topo_k8s_kubeconfigstringPath to a valid kubeconfig file.
-topo_k8s_namespacestringThe kubernetes namespace to use for all objects. Default comes from the context or in-cluster config
-topo_read_concurrencyintconcurrent topo reads (default 32)
-topo_zk_auth_filestringauth to use when connecting to the zk topo server, file contents should be :, e.g., digest:user:pass
-topo_zk_base_timeoutdurationzk base timeout (see zk.Connect) (default 30s)
-topo_zk_max_concurrencyintmaximum number of pending requests to send to a Zookeeper server. (default 64)
-topo_zk_tls_castringthe server ca to use to validate servers when connecting to the zk topo server
-topo_zk_tls_certstringthe cert to use to connect to the zk topo server, requires topo_zk_tls_key, enables TLS
-topo_zk_tls_keystringthe key to use to connect to the zk topo server, enables TLS
-tracerstringtracing service to use (default “noop”)
-tracing-sampling-ratefloatsampling rate for the probabilistic jaeger sampler (default 0.1)
-transaction_modestringSINGLE: disallow multi-db transactions, MULTI: allow multi-db transactions with best effort commit, TWOPC: allow multi-db transactions with 2pc commit (default “MULTI”)
-vvaluelog level for V logs
-versionbooleanprint binary version
-vmodulevaluecomma-separated list of pattern=N settings for file-filtered logging
-vschema_ddl_authorized_usersstringList of users authorized to execute vschema ddl operations, or ‘%’ to allow all users.
-vtctld_addrstringaddress of a vtctld instance
-vtgate-config-terse-errorsbooleanprevent bind vars from escaping in returned errors
-warn_memory_rowsintWarning threshold for in-memory results. A row count higher than this amount will cause the VtGateWarnings.ResultsExceeded counter to be incremented. (default 30000)