Configuration

GreptimeDB supports layered configuration and uses the following precedence order(each item takes precedence over the item below it):

• Command-line options
• Configuration file
• Environment variables
• Default values

This page describes methods for configuring GreptimeDB server settings. Configuration can be set in TOML file.

The system assigns a default value for missing parameters in the configuration file.

All sample configuration files are in the project's config folder.

Command-line options

See Command lines to learn how to use the greptime command line.

Global options

• -h/--help: Print help information;
• -V/--version: Print version information;
• --log-dir <LOG_DIR>: The logging directory;
• --log-level <LOG_LEVEL>: The logging level;

Datanode subcommand options

You can list all the options from the following command:

greptime datanode start --help

• -c/--config-file: The configuration file for datanode;
• --data-home: Database storage root directory;
• --env-prefix <ENV_PREFIX>: The prefix of environment variables, default is GREPTIMEDB_DATANODE;
• --http-addr <HTTP_ADDR>: HTTP server address;
• --http-timeout <HTTP_TIMEOUT>: HTTP request timeout in seconds.
• --metasrv-addr <METASRV_ADDR>: Metasrv address list;
• --node-id <NODE_ID>: The datanode ID;
• --rpc-addr <RPC_ADDR>: The datanode RPC addr;
• --rpc-hostname <RPC_HOSTNAME>: The datanode hostname;
• --wal-dir <WAL_DIR>: The directory of WAL;

All the addr options are in the form of ip:port.

Metasrv subcommand options

You can list all the options from the following command:

greptime metasrv start --help

• -c/--config-file: The configuration file for metasrv;
• --enable-region-failover: Whether to enable region failover, default is false.
• --env-prefix <ENV_PREFIX>: The prefix of environment variables, default is GREPTIMEDB_METASRV;
• --bind-addr <BIND_ADDR>: The bind address of metasrv;
• --http-addr <HTTP_ADDR>: HTTP server address;
• --http-timeout <HTTP_TIMEOUT>: HTTP request timeout in seconds.
• --selector <SELECTOR>: You can refer selector-type;
• --server-addr <SERVER_ADDR>: The communication server address for frontend and datanode to connect to metasrv;
• --store-addr <STORE_ADDR>: Comma separated etcd server addresses to store metadata;
• --use-memory-store: Use memory store instead of etcd, for test purpose only;

Frontend subcommand options

You can list all the options from the following command:

greptime frontend start --help

• -c/--config-file: The configuration file for frontend;
• --disable-dashboard: Disable dashboard http service, default is false.
• --env-prefix <ENV_PREFIX>: The prefix of environment variables, default is GREPTIMEDB_FRONTEND;
• --rpc-addr <RPC_ADDR>: GRPC server address;
• --http-addr <HTTP_ADDR>: HTTP server address;
• --http-timeout <HTTP_TIMEOUT>: HTTP request timeout in seconds.
• --influxdb-enable: Whether to enable InfluxDB protocol in HTTP API;
• --metasrv-addr <METASRV_ADDR>: Metasrv address list;
• --mysql-addr <MYSQL_ADDR>: MySQL server address;
• --opentsdb-addr <OPENTSDB_ADDR>: OpenTSDB server address;
• --postgres-addr <POSTGRES_ADDR>: Postgres server address;
• --tls-cert-path <TLS_CERT_PATH>: The TLS public key file path;
• --tls-key-path <TLS_KEY_PATH>: The TLS private key file path;
• --tls-mode <TLS_MODE>: TLS Mode;
• --user-provider <USER_PROVIDER>: You can refer authentication;

Standalone subcommand options

You can list all the options from the following command:

greptime standalone start --help

• -c/--config-file: The configuration file for frontend;
• --env-prefix <ENV_PREFIX>: The prefix of environment variables, default is GREPTIMEDB_STANDALONE;
• --http-addr <HTTP_ADDR>: HTTP server address;
• --influxdb-enable: Whether to enable InfluxDB protocol in HTTP API;
• --mysql-addr <MYSQL_ADDR>: MySQL server address;
• --opentsdb-addr <OPENTSDB_ADDR>: OpenTSDB server address;
• --postgres-addr <POSTGRES_ADDR>: Postgres server address;
• --rpc-addr <RPC_ADDR>: gRPC server address;

Configuration File

Examples

Configurations can be used in one or multiple components according to their features. You can find all available configurations for each component on GitHub:

• standalone
• frontend
• datanode
• metasrv

Specify configuration file

You can specify the configuration file by using the command line arg -c [file_path].

greptime [standalone | frontend | datanode | metasrv]  start -c config/standalone.example.toml

For example, start the standalone as below:

greptime standalone start -c standalone.example.toml

Protocol options

Protocol options are valid in frontend and standalone sub commands, which specify the protocol server addresses and other protocol-related options.

Below is an example configuration with default values. The HTTP and gRPC protocols must be enabled for the database to work correctly. The other protocols are optional. If you want to disable certain protocols, such as OpenTSDB protocol support, you can set the enable parameter to false.

[http]
addr = "127.0.0.1:4000"
timeout = "30s"
body_limit = "64MB"

[grpc]
addr = "127.0.0.1:4001"
runtime_size = 8

[mysql]
enable = true
addr = "127.0.0.1:4002"
runtime_size = 2

[mysql.tls]
mode = "disable"
cert_path = ""
key_path = ""

[postgres]
enable = true
addr = "127.0.0.1:4003"
runtime_size = 2

[postgres.tls]
mode = "disable"
cert_path = ""
key_path = ""

[opentsdb]
enable = true
addr = "127.0.0.1:4242"
runtime_size = 2

[influxdb]
enable = true

[prom_store]
enable = true

The following table describes the options in detail:

Option	Key	Type	Description
http			HTTP server options
	addr	String	Server address, "127.0.0.1:4000" by default
	timeout	String	HTTP request timeout, "30s" by default
	body_limit	String	HTTP max body size, "64MB" by default
grpc			gRPC server options
	addr	String	Server address, "127.0.0.1:4001" by default
	runtime_size	Integer	The number of server worker threads, 8 by default
mysql			MySQL server options
	enable	Boolean	Whether to enable MySQL protocol, true by default
	add	String	Server address, "127.0.0.1:4002" by default
	runtime_size	Integer	The number of server worker threads, 2 by default
influxdb			InfluxDB Protocol options
	enable	Boolean	Whether to enable InfluxDB protocol in HTTP API, true by default
opentsdb			OpenTSDB Protocol options
	enable	Boolean	Whether to enable OpenTSDB protocol, true by default
	addr	String	OpenTSDB telnet API server address, "127.0.0.1:4242" by default
	runtime_size	Integer	The number of server worker threads, 2 by default
prom_store			Prometheus remote storage options
	enable	Boolean	Whether to enable Prometheus remote write and read in HTTP API, true by default
postgres			PostgresSQL server options
	enable	Boolean	Whether to enable PostgresSQL protocol, true by default
	addr	String	Server address, "127.0.0.1:4003" by default
	runtime_size	Integer	The number of server worker threads, 2 by default

Storage options

The storage options are valid in datanode and standalone mode, which specify the database data directory and other storage-related options.

GreptimeDB supports storing data in local file system, AWS S3 and compatible services (including MinIO, digitalocean space, Tencent Cloud Object Storage(COS), Baidu Object Storage(BOS) and so on), Azure Blob Storage and Aliyun OSS.

Option	Key	Type	Description
storage			Storage options
	type	String	Storage type, supports "File", "S3" and "Oss" etc.
File			Local file storage options, valid when type="File"
	data_home	String	Database storage root directory, "/tmp/greptimedb" by default
S3			AWS S3 storage options, valid when type="S3"
	bucket	String	The S3 bucket name
	root	String	The root path in S3 bucket
	endpoint	String	The API endpoint of S3
	region	String	The S3 region
	access_key_id	String	The S3 access key id
	secret_access_key	String	The S3 secret access key
Oss			Aliyun OSS storage options, valid when type="Oss"
	bucket	String	The OSS bucket name
	root	String	The root path in OSS bucket
	endpoint	String	The API endpoint of OSS
	access_key_id	String	The OSS access key id
	secret_access_key	String	The OSS secret access key
Azblob			Azure Blob Storage options, valid when type="Azblob"
	container	String	The container name
	root	String	The root path in container
	endpoint	String	The API endpoint of Azure Blob Storage
	account_name	String	The account name of Azure Blob Storage
	account_key	String	The access key
	sas_token	String	The shared access signature
Gsc			Google Cloud Storage options, valid when type="Gsc"
	root	String	The root path in Gsc bucket
	bucket	String	The Gsc bucket name
	scope	String	The Gsc service scope
	credential_path	String	The Gsc credentials path
	endpoint	String	The API endpoint of Gsc

A file storage sample configuration:

[storage]
type = "File"
data_home = "/tmp/greptimedb/"

A S3 storage sample configuration:

[storage]
type = "S3"
bucket = "test_greptimedb"
root = "/greptimedb"
access_key_id = "<access key id>"
secret_access_key = "<secret access key>"

Storage engine provider

[[storage.providers]] setups the table storage engine providers. Based on these providers, you can create a table with a specified storage, see create table:

# Allows using multiple storages
[[storage.providers]]
type = "S3"
bucket = "test_greptimedb"
root = "/greptimedb"
access_key_id = "<access key id>"
secret_access_key = "<secret access key>"

[[storage.providers]]
type = "Gcs"
bucket = "test_greptimedb"
root = "/greptimedb"
credential_path = "<gcs credential path>"

All configured providers can be used as the storage option when creating tables.

Object storage cache

When using S3, OSS or Azure Blob Storage, it's better to enable object storage caching for speedup data querying:

[storage]
type = "S3"
bucket = "test_greptimedb"
root = "/greptimedb"
access_key_id = "<access key id>"
secret_access_key = "<secret access key>"
## Enable object storage caching
cache_path = "/var/data/s3_local_cache"
cache_capacity = "256MiB"

The cache_path is the local file directory that keeps cache files, and the cache_capacity is the maximum total file size in the cache directory.

WAL options

The [wal] section in datanode or standalone config file configures the options of Write-Ahead-Log:

[wal]
file_size = "256MB"
purge_threshold = "4GB"
purge_interval = "10m"
read_batch_size = 128
sync_write = false

• dir: is the directory where to write logs. When using File storage, it's {data_home}/wal by default. It must be configured explicitly when using other storage types such as S3 etc.
• file_size: the maximum size of the WAL log file, default is 256MB.
• purge_threshold and purge_interval: control the purging of wal files, default is 4GB.
• sync_write: whether to call fsync when writing every log.

Logging options

frontend, metasrv, datanode and standalone can all configure log and tracing related parameters in the [logging] section:

[logging]
dir = "/tmp/greptimedb/logs"
level = "info"
enable_otlp_tracing = false
otlp_endpoint = "localhost:4317"
tracing_sample_ratio = 1.0
append_stdout = true

• dir: log output directory.
• level: output log level, available log level are info, debug, error, warn, the default level is info.
• enable_otlp_tracing: whether to turn on tracing, not turned on by default.
• otlp_endpoint: Export the target endpoint of tracing using gRPC-based OTLP protocol, the default value is localhost:4317.
• tracing_sample_ratio: The percentage of sampling tracing, the value range is [0,1], the default value is 1, which means sampling all tracing.
• append_stdout: Whether to append logs to stdout. Defaults to true.

How to use distributed tracing, please reference Tracing

Region engine options

The parameters corresponding to different storage engines can be configured for datanode and standalone in the [region_engine] section. Currently, there is only one storage engine available, which is mito.

[[region_engine]]
[region_engine.mito]
num_workers = 1
manifest_checkpoint_distance = 10
max_background_jobs = 4
global_write_buffer_size = "1GB"
global_write_buffer_reject_size = "2GB"

• num_workers: Number of write threads
• manifest_checkpoint_distance: Create a checkpoint every manifest_checkpoint_distance manifest files are written
• max_background_jobs: Number of background threads
• global_write_buffer_size: Size of the write buffer, default is 1GB
• global_write_buffer_reject_size: Reject write requests when the size of data in the write buffer exceeds global_write_buffer_reject_size. It needs to be larger than global_write_buffer_size, default is 2GB

Specify meta client

The meta_client options are valid in datanode and frontend mode, which specify the Metasrv client information.

metasrv_addrs = ["127.0.0.1:3002"]
timeout = "3s"
connect_timeout = "1s"
ddl_timeout = "10s"
tcp_nodelay = true

The meta_client configures the Metasrv client, including:

• metasrv_addrs: The Metasrv address list.
• timeout: operation timeout, 3s by default.
• connect_timeout, connect server timeout, 1s by default.
• ddl_timeout, DDL execution timeout, 10s by default.
• tcp_nodelay, TCP_NODELAY option for accepted connections, true by default.

Monitor metrics options

These options are used to save system metrics to GreptimeDB itself. For instructions on how to use this feature, please refer to the Monitoring guide.

[export_metrics]
# Whether to enable export_metrics
enable=true
# Export time interval
write_interval = "30s"

• enable: Whether to enable export_metrics, false by default.
• write_interval: Export time interval.

self_import method

Only frontend and standalone support exporting metrics using self_import method.

[export_metrics]
# Whether to enable export_metrics
enable=true
# Export time interval
write_interval = "30s"
[export_metrics.self_import]
db = "information_schema"

• db: The default database used by self_import is information_schema. You can also create another database for saving system metrics.

remote_write method

The remote_write method is supported by datanode, frontend, metasrv, and standalone. It sends metrics to a receiver compatible with the Prometheus Remote-Write protocol.

[export_metrics]
# Whether to enable export_metrics
enable=true
# Export time interval
write_interval = "30s"
[export_metrics.remote_write]
# URL specified by Prometheus Remote-Write protocol
url = "http://127.0.0.1:4000/v1/prometheus/write?db=information_schema"
# Some optional HTTP parameters, such as authentication information
headers = { Authorization = "Basic Z3JlcHRpbWVfdXNlcjpncmVwdGltZV9wd2Q=" }

• url: URL specified by Prometheus Remote-Write protocol.
• headers: Some optional HTTP parameters, such as authentication information.

Mode option

The mode option is valid in datanode, frontend and standalone, which specify the running mode of the component.

In the configuration files of datanode and frontend of distributed GreptimeDB, the value needs to be set as distributed:

mode = "distributed"

In the configuration files of standalone GreptimeDB, the value needs to be set as standalone:

mode = "standalone"

Metasrv-only configuration

# The working home directory.
data_home = "/tmp/metasrv/"
# The bind address of metasrv, "127.0.0.1:3002" by default.
bind_addr = "127.0.0.1:3002"
# The communication server address for frontend and datanode to connect to metasrv,  "127.0.0.1:3002" by default for localhost.
server_addr = "127.0.0.1:3002"
# Etcd server addresses, "127.0.0.1:2379" by default.
store_addr = "127.0.0.1:2379"
# Datanode selector type.
# - "lease_based" (default value).
# - "load_based"
# For details, please see "https://docs.greptime.com/contributor-guide/meta/selector".
selector = "LeaseBased"
# Store data in memory, false by default.
use_memory_store = false

Key	Type	Description
data_home	String	The working home of Metasrv, "/tmp/metasrv/" by default
bind_addr	String	The bind address of Metasrv, "127.0.0.1:3002" by default.
server_addr	String	The communication server address for frontend and datanode to connect to Metasrv, "127.0.0.1:3002" by default for localhost
store_addr	String	etcd server addresses, "127.0.0.1:2379" by default, server address separated by commas, in the format of "ip1:port1,ip2:port2,...".
selector	String	Load balance strategy to choose datanode when creating new tables, see Selector
use_memory_store	Boolean	Only used for testing when you don't have an etcd cluster, store data in memory, false by default.

Datanode-only configuration

node_id = 42
rpc_hostname = "127.0.0.1"
rpc_addr = "127.0.0.1:3001"
rpc_runtime_size = 8

Key	Type	Description
node_id	Integer	The datanode identifier, should be unique.
rpc_hostname	String	Hostname of this node.
rpc_addr	String	gRPC server address, "127.0.0.1:3001" by default.
rpc_runtime_size	Integer	The number of gRPC server worker threads, 8 by default.

Environment variable

Every item in the configuration file can be mapped into environment variables. For example, if we want to set the configuration item data_home of the datanode by environment variable:

# ...
[storage]
data_home = "/data/greptimedb"
# ...

You can use the following shell command to setup the environment variable as the following format:

export GREPTIMEDB_DATANODE__STORAGE__DATA_HOME=/data/greptimedb

Environment Variable Rules

• Every environment variable should have the component prefix, for example:

  • GREPTIMEDB_FRONTEND
  • GREPTIMEDB_METASRV
  • GREPTIMEDB_DATANODE
  • GREPTIMEDB_STANDALONE

• We use double underscore __ as a separator. For example, the above data structure storage.data_home will be transformed to STORAGE__DATA_HOME.

The environment variable also accepts list that are separated by a comma ,, for example:

GREPTIMEDB_METASRV__META_CLIENT__METASRV_ADDRS=127.0.0.1:3001,127.0.0.1:3002,127.0.0.1:3003