Node-specific settings¶

Table of contents

Basics ¶

cluster.name: Default: crate

Runtime: no

The name of the CrateDB cluster the node should join to.

node.name: Runtime: no

The name of the node. If no name is configured a random one will be generated.

Note

Node names must be unique in a CrateDB cluster.

node.store.allow_mmap: Default: true

Runtime: no

The setting indicates whether or not memory-mapping is allowed.

Node types ¶

CrateDB supports different types of nodes.

The following settings can be used to differentiate nodes upon startup:

node.master: Default: true

Runtime: no

Whether or not this node is able to get elected as master node in the cluster.

node.data: Default: true

Runtime: no

Whether or not this node will store data.

Using different combinations of these two settings, you can create four different types of node. Each type of node is differentiated by what types of load it will handle.

Tabulating the truth values for node.master and node.data produces a truth table outlining the four different types of node:

	Master	No master
Data	Handle all loads.	Handles client requests and query execution.
No data	Handles cluster management.	Handles client requests.

Nodes marked as node.master will only handle cluster management if they are elected as the cluster master. All other loads are shared equally.

General ¶

node.sql.read_only: Default: false

Runtime: no

If set to true, the node will only allow SQL statements which are resulting in read operations.

statement_timeout

Default: 0

Runtime: yes

The maximum duration of any statement before it gets cancelled.

This value is used as default value for the statement_timeout session setting

If 0 queries are allowed to run infinitely and don’t get cancelled automatically.

Note

Updating this setting won’t affect existing sessions, it will only take effect for new sessions.

This defines the TCP port range to which the CrateDB HTTP service will be bound to. It defaults to 4200-4300. Always the first free port in this range is used. If this is set to an integer value it is considered as an explicit single port.

The HTTP protocol is used for the REST endpoint which is used by all clients except the Java client.

http.publish_port: Runtime: no

The port HTTP clients should use to communicate with the node. It is necessary to define this setting if the bound HTTP port (http.port) of the node is not directly reachable from outside, e.g. running it behind a firewall or inside a Docker container.

transport.tcp.port

Runtime: no

This defines the TCP port range to which the CrateDB transport service will be bound to. It defaults to 4300-4400. Always the first free port in this range is used. If this is set to an integer value it is considered as an explicit single port.

The transport protocol is used for internal node-to-node communication.

transport.publish_port: Runtime: no

The port that the node publishes to the cluster for its own discovery. It is necessary to define this setting when the bound tranport port (transport.tcp.port) of the node is not directly reachable from outside, e.g. running it behind a firewall or inside a Docker container.

psql.port: Runtime: no

This defines the TCP port range to which the CrateDB Postgres service will be bound to. It defaults to 5432-5532. Always the first free port in this range is used. If this is set to an integer value it is considered as an explicit single port.

Advanced TCP settings ¶

Any interface that uses TCP (Postgres wire, HTTP & Transport protocols) shares the following settings:

network.tcp.no_delay: Default: true

Runtime: no

Enable or disable the Nagle’s algorithm for buffering TCP packets. Buffering is disabled by default.

network.tcp.keep_alive: Default: true

Runtime: no

Configures the SO_KEEPALIVE option for sockets, which determines whether they send TCP keepalive probes.

network.tcp.reuse_address: Default: true on non-windows machines and false otherwise

Runtime: no

Configures the SO_REUSEADDRS option for sockets, which determines whether they should reuse the address.

network.tcp.send_buffer_size: Default: -1

Runtime: no

The size of the TCP send buffer (SO_SNDBUF socket option). By default not explicitly set.

network.tcp.receive_buffer_size: Default: -1

Runtime: no

The size of the TCP receive buffer (SO_RCVBUF socket option). By default not explicitly set.

Note

Each setting in this section has its counterpart for HTTP and transport. To provide a protocol specific setting, remove network prefix and use either http or transport instead. For example, no_delay can be configured as http.tcp.no_delay and transport.tcp.no_delay. Please note, that PG interface takes its settings from transport.

Transport settings ¶

transport.connect_timeout: Default: 30s

Runtime: no

The connect timeout for initiating a new connection.

transport.compress: Default: false

Runtime: no

Set to true to enable compression (DEFLATE) between all nodes.

transport.ping_schedule: Default: -1

Runtime: no

Schedule a regular application-level ping message to ensure that transport connections between nodes are kept alive. Defaults to -1 (disabled). It is preferable to correctly configure TCP keep-alives instead of using this feature, because TCP keep-alives apply to all kinds of long-lived connections and not just to transport connections.

Paths ¶

Note

Relative paths are relative to CRATE_HOME. Absolute paths override this behavior.

path.conf: Default: config

Runtime: no

Filesystem path to the directory containing the configuration files crate.yml and log4j2.properties.

path.data

Default: data

Runtime: no

Filesystem path to the directory where this CrateDB node stores its data (table data and cluster metadata).

Multiple paths can be set by using a comma separated list and each of these paths will hold full shards (instead of striping data across them). For example:

path.data: /path/to/data1,/path/to/data2

When CrateDB finds striped shards at the provided locations (from CrateDB <0.55.0), these shards will be migrated automatically on startup.

path.logs

Default: logs

Runtime: no

Filesystem path to a directory where log files should be stored.

Can be used as a variable inside log4j2.properties.

For example:

appender:
  file:
    file: ${path.logs}/${cluster.name}.log

path.repo

Runtime: no

A list of filesystem or UNC paths where repositories of type fs may be stored.

Without this setting a CrateDB user could write snapshot files to any directory that is writable by the CrateDB process. To safeguard against this security issue, the possible paths have to be whitelisted here.

See also location setting of repository type fs.

Plug-ins ¶

plugin.mandatory

Runtime: no

A list of plug-ins that are required for a node to startup.

If any plug-in listed here is missing, the CrateDB node will fail to start.

CPU ¶

processors

Runtime: no

The number of processors is used to set the size of the thread pools CrateDB is using appropriately. If not set explicitly, CrateDB will infer the number from the available processors on the system.

In environments where the CPU amount can be restricted (like Docker) or when multiple CrateDB instances are running on the same hardware, the inferred number might be too high. In such a case, it is recommended to set the value explicitly.

Memory ¶

bootstrap.memory_lock: Default: false

Runtime: no

CrateDB performs poorly when the JVM starts swapping: you should ensure that it never swaps. If set to true, CrateDB will use the mlockall system call on startup to ensure that the memory pages of the CrateDB process are locked into RAM.

Garbage collection ¶

CrateDB logs if JVM garbage collection on different memory pools takes too long. The following settings can be used to adjust these timeouts:

monitor.jvm.gc.collector.young.warn: Default: 1000ms

Runtime: no

CrateDB will log a warning message if it takes more than the configured timespan to collect the Eden Space (heap).

monitor.jvm.gc.collector.young.info: Default: 700ms

Runtime: no

CrateDB will log an info message if it takes more than the configured timespan to collect the Eden Space (heap).

monitor.jvm.gc.collector.young.debug: Default: 400ms

Runtime: no

CrateDB will log a debug message if it takes more than the configured timespan to collect the Eden Space (heap).

monitor.jvm.gc.collector.old.warn: Default: 10000ms

Runtime: no

CrateDB will log a warning message if it takes more than the configured timespan to collect the Old Gen / Tenured Gen (heap).

monitor.jvm.gc.collector.old.info: Default: 5000ms

Runtime: no

CrateDB will log an info message if it takes more than the configured timespan to collect the Old Gen / Tenured Gen (heap).

monitor.jvm.gc.collector.old.debug: Default: 2000ms

Runtime: no

CrateDB will log a debug message if it takes more than the configured timespan to collect the Old Gen / Tenured Gen (heap).

Authentication ¶

Trust authentication ¶

auth.trust.http_default_user: Default: crate

Runtime: no

The default user that should be used for authentication when clients connect to CrateDB via HTTP protocol and they do not specify a user via the Authorization request header.

auth.trust.http_support_x_real_ip: Default: false

Runtime: no

If enabled, the HTTP transport will trust the X-Real-IP header sent by the client to determine the client’s IP address. This is useful when CrateDB is running behind a reverse proxy or load-balancer. For improved security, any _local_ IP address (127.0.0.1 and ::1) defined in this header will be ignored.

Warning

Enabling this setting can be a security risk, as it allows clients to impersonate other clients by sending a fake X-Real-IP header.

Host-based authentication ¶

Authentication settings (auth.host_based.*) are node settings, which means that their values apply only to the node where they are applied and different nodes may have different authentication settings.

auth.host_based.enabled: Default: false

Runtime: no

Setting to enable or disable Host Based Authentication (HBA). It is disabled by default.

HBA entries ¶

The auth.host_based.config. setting is a group setting that can have zero, one or multiple groups that are defined by their group key (${order}) and their fields (user, address, method, protocol, ssl).

${order}:: An identifier that is used as a natural order key when looking up the host

based configuration entries. For example, an order key of a will be

looked up before an order key of b. This key guarantees that the entry

lookup order will remain independent from the insertion order of the

entries.

The Host-Based Authentication (HBA) setting is a list of predicates that users can specify to restrict or allow access to CrateDB.

The meaning of the fields of the are as follows:

auth.host_based.config.${order}.user: Runtime: no

Specifies an existing CrateDB username, only crate user (superuser) is

available. If no user is specified in the entry, then all existing users

can have access.

auth.host_based.config.${order}.address: Runtime: no

The client machine addresses that the client matches, and which are allowed

to authenticate. This field may contain an IPv4 address, an IPv6 address or

an IPv4 CIDR mask. For example: 127.0.0.1 or 127.0.0.1/32. It also

may contain a hostname or the special _local_ notation which will match

both IPv4 and IPv6 connections from localhost. A hostname specification

that starts with a dot (.) matches a suffix of the actual hostname.

So .crate.io would match foo.crate.io but not just crate.io. If no address

is specified in the entry, then access to CrateDB is open for all hosts.

auth.host_based.config.${order}.method: Runtime: no

The authentication method to use when a connection matches this entry.

Valid values are trust, cert, and password. If no method is

specified, the trust method is used by default.

See Trust method, Client certificate authentication method and Password authentication method for more

information about these methods.

auth.host_based.config.${order}.protocol: Runtime: no

Specifies the protocol for which the authentication entry should be used.

If no protocol is specified, then this entry will be valid for all

protocols that rely on host based authentication see Trust method).

auth.host_based.config.${order}.ssl: Default: optional

Runtime: no

Specifies whether the client must use SSL/TLS to connect to the cluster.

If set to on then the client must be connected through SSL/TLS

otherwise is not authenticated. If set to off then the client must

not be connected via SSL/TLS otherwise is not authenticated. Finally

optional, which is the value when the option is completely skipped,

means that the client can be authenticated regardless of SSL/TLS is used

or not.

Example of config groups:

auth.host_based.config:
  entry_a:
    user: crate
    address: 127.16.0.0/16
  entry_b:
    method: trust
  entry_3:
    user: crate
    address: 172.16.0.0/16
    method: trust
    protocol: pg
    ssl: on

Secured communications (SSL/TLS)¶

Secured communications via SSL allows you to encrypt traffic between CrateDB nodes and clients connecting to them. Connections are secured using Transport Layer Security (TLS).

ssl.http.enabled: Default: false

Runtime: no

Set this to true to enable secure communication between the CrateDB node and the client through SSL via the HTTPS protocol.

ssl.psql.enabled: Default: false

Runtime: no

Set this to true to enable secure communication between the CrateDB node and the client through SSL via the PostgreSQL wire protocol.

ssl.transport.mode

Default: legacy

Runtime: no

For communication between nodes, choose:

off: SSL cannot be used
legacy: SSL is not used. If HBA is enabled, transport connections won’t be verified Any reachable host can establish a connection.
on: SSL must be used

ssl.keystore_filepath: Runtime: no

The full path to the node keystore file.

ssl.keystore_password: Runtime: no

The password used to decrypt the keystore file defined with ssl.keystore_filepath.

ssl.keystore_key_password: Runtime: no

The password entered at the end of the keytool -genkey command.

Note

Optionally trusted CA certificates can be stored separately from the node’s keystore into a truststore for CA certificates.

ssl.truststore_filepath: Runtime: no

The full path to the node truststore file. If not defined, then only a keystore will be used.

ssl.truststore_password: Runtime: no

The password used to decrypt the truststore file defined with ssl.truststore_filepath.

ssl.resource_poll_interval: Default: 5m

Runtime: no

The frequency at which SSL files such as keystore and truststore are polled for changes.

Blobs ¶

blobs.path

Runtime: no

Path to a filesystem directory where to store blob data allocated for this node.

By default blobs will be stored under the same path as normal data. A relative path value is interpreted as relative to CRATE_HOME.

Repositories ¶

Repositories are used to backup a CrateDB cluster.

repositories.url.allowed_urls

Runtime: no

This setting only applies to repositories of type url.

With this setting a list of urls can be specified which are allowed to be used if a repository of type url is created.

Wildcards are supported in the host, path, query and fragment parts.

This setting is a security measure to prevent access to arbitrary resources.

In addition, the supported protocols can be restricted using the repositories.url.supported_protocols setting.

repositories.url.supported_protocols

Default: http, https, ftp, file and jar

Runtime: no

A list of protocols that are supported by repositories of type url.

The jar protocol is used to access the contents of jar files. For more info, see the java JarURLConnection documentation.

Queries ¶

indices.query.bool.max_clause_count: Default: 8192

Runtime: no

This setting defines the maximum number of elements an array can have so that the != ANY(), LIKE ANY(), ILIKE ANY(), NOT LIKE ANY() and the NOT ILIKE ANY() operators can be applied on it.

Note

Increasing this value to a large number (e.g. 10M) and applying those ANY operators on arrays of that length can lead to heavy memory, consumption which could cause nodes to crash with OutOfMemory exceptions.

Legacy ¶

legacy.table_function_column_naming

Default: false

Runtime: no

Since CrateDB 5.0.0, if the table function is not aliased and is returning a single base data typed column, the table function name is used as the column name. This setting can be set in order to use the naming convention prior to 5.0.0.

The following table functions are affected by this setting:

When the setting is set and a single column is expected to be returned, the returned column will be named col1, groups, or col1 respectively.

Note

Beware that if not all nodes in the cluster are consistently set or unset, the behaviour will depend on the node handling the query.

JavaScript language ¶

lang.js.enabled: Default: true

Runtime: no

Setting to enable or disable JavaScript UDF support.

Custom attributes ¶

The node.attr namespace is a bag of custom attributes. Custom attributes can be used to control shard allocation.

You can create any attribute you want under this namespace, like node.attr.key: value. These attributes use the node.attr namespace to distinguish them from core node attribute like node.name.

Custom attributes are not validated by CrateDB, unlike core node attributes.

`_local_`	Any loopback addresses on the system, for example `127.0.0.1`.
`_site_`	Any site-local addresses on the system, for example `192.168.0.1`.
`_global_`	Any globally-scoped addresses on the system, for example `8.8.8.8`.
`_[INTERFACE]_`	Addresses of a network interface, for example `_en0_`.

Node-specific settings¶

Basics ¶

Node types ¶

General ¶

Networking ¶

Hosts ¶

Ports ¶

Advanced TCP settings ¶

Transport settings ¶

Paths ¶

Plug-ins ¶

CPU ¶

Memory ¶

Garbage collection ¶

Authentication ¶

Trust authentication ¶

Host-based authentication ¶

HBA entries ¶

Secured communications (SSL/TLS)¶

Blobs ¶

Repositories ¶

Queries ¶

Legacy ¶

JavaScript language ¶

Custom attributes ¶

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