NOTICE: CURRENT IoTDB CLUSTER IS FOR TESTING NOW! PLEASE BE DELIBERATE IF YOU RUN IT IN PRODUCT ENVIRONMENT.

Cluster Setup

For installation prerequisites, please refer to QuickStart

Prerequisite

Note: Please install MinGW or WSL or git bash if you are using Windows.

Start Service

Users can build clusters in pseudo-distributed mode or distributed mode. The main difference between pseudo-distributed mode and distributed mode is the difference in seed_nodes in the configuration file. For detail descriptions, please refer to Cluster Configuration Items.

To start the service of one of the nodes, you need to execute the following commands:

1. # Unix/OS X
2. > nohup sbin/start-node.sh [printgc] [<conf_path>] >/dev/null 2>&1 &

4. # Windows
5. > sbin\start-node.bat [printgc] [<conf_path>]

printgc means whether enable the gc and print gc logs when start the node, <conf_path> use the configuration file in the conf_path folder to override the default configuration file.

OverWrite the configurations of Stand-alone node

Some configurations in the iotdb-engines.properties will be ignored

  • enable_auto_create_schema is always considered as false. Use enable_auto_create_schema in iotdb-cluster.properties to enable it, instead.
  • is_sync_enable is always considered as false.

Cluster Configuration Items

Before starting to use IoTDB, you need to config the configuration files first. For your convenience, we have already set the default config in the files.

In total, we provide users four kinds of configurations module:

  • environment configuration file (iotdb-env.bat, iotdb-env.sh). The default configuration file for the environment configuration item. Users can configure the relevant system configuration items of JAVA-JVM in the file.
  • system configuration file (iotdb-engine.properties). The default configuration file for the IoTDB engine layer configuration item. Users can configure the IoTDB engine related parameters in the file, such as the precision of timestamp(timestamp_precision), etc. What’s more, Users can configure settings of TsFile (the data files), such as the data size written to the disk per time(group_size_in_byte).
  • log configuration file (logback.xml). The default log configuration file, such as the log levels.
  • iotdb-cluster.properties. Some configurations required by IoTDB cluster. Such as replication number(default_replica_num), etc.

For detailed description of the two configuration files iotdb-engine.properties, iotdb-env.sh/iotdb-env.bat, please refer to Configuration Manual. The configuration items described below are in the iotdb-cluster.properties file, you can also review the comments in the configuration fileCluster Setup - 图1 (opens new window) directly.

  • internal_ip
Name internal_ip
Description IP address of internal communication between nodes in IOTDB cluster, such as heartbeat, snapshot, raft log, etc
Type String
Default 127.0.0.1
Effective After restart system, shall NOT change after cluster is up
  • internal_meta_port
Name internal_meta_port
Description IoTDB meta service port, for meta group’s communication, which involves all nodes and manages the cluster configuration and storage groups. IoTDB will automatically create a heartbeat port for each meta service. The default meta service heartbeat port is internal_meta_port+1, please confirm that these two ports are not reserved by the system and are not occupied
Type Int32
Default 9003
Effective After restart system, shall NOT change after cluster is up
  • internal_data_port
Name internal_data_port
Description IoTDB data service port, for data groups’ communication, each consists of one node and its replicas, managing timeseries schemas and data. IoTDB will automatically create a heartbeat port for each data service. The default data service heartbeat port is internal_data_port+1. Please confirm that these two ports are not reserved by the system and are not occupied
Type Int32
Default 40010
Effective After restart system, shall NOT change after cluster is up
  • open_server_rpc_port
Name open_server_rpc_port
Description whether open port for server module (for debug purpose), if true, the single’s server rpc_port will be changed to rpc_port (in iotdb-engines.properties) + 1
Type Boolean
Default False
Effective After restart system
  • seed_nodes
Name seed_nodes
Description The address of the nodes in the cluster, {IP/DOMAIN}:internal_meta_port format, separated by commas; for the pseudo-distributed mode, you can fill in localhost, or 127.0.0.1 or mixed, but the real ip address cannot appear; for the distributed mode, real ip or hostname is supported, but localhost or 127.0.0.1 cannot appear. When used by start-node.sh(.bat), this configuration means the nodes that will form the initial cluster, so every node that use start-node.sh(.bat) should have the same seed_nodes, or the building of the initial cluster will fail. WARNING: if the initial cluster is built, this should not be changed before the environment is cleaned. When used by add-node.sh(.bat), this means the nodes to which that the application of joining the cluster will be sent, as all nodes can respond to a request, this configuration can be any nodes that already in the cluster, unnecessary to be the nodes that were used to build the initial cluster by start-node.sh(.bat). Several nodes will be picked randomly to send the request, the number of nodes picked depends on the number of retries.
Type String
Default 127.0.0.1:9003,127.0.0.1:9005,127.0.0.1:9007
Effective After restart system
  • rpc_thrift_compression_enable
Name rpc_thrift_compression_enable
Description Whether to enable thrift compression, Note that this parameter should be consistent with each node and with the client, and also consistent with the rpc_thrift_compression_enable parameter in iotdb-engine.properties
Type Boolean
Default false
Effective After restart system, must be changed with all other nodes
  • default_replica_num
Name default_replica_num
Description Number of cluster replicas of timeseries schema and data. Storage group info is always fully replicated in all nodes.
Type Int32
Default 3
Effective After restart system, shall NOT change after cluster is up
  • cluster_name
Name cluster_name
Description Cluster name is used to identify different clusters, cluster_name of all nodes in a cluster must be the same
Type String
Default default
Effective After restart system
  • connection_timeout_ms
Name connection_timeout_ms
Description Heartbeat timeout time period between nodes in the same raft group, in milliseconds
Type Int32
Default 20000
Effective After restart system
  • read_operation_timeout_ms
Name read_operation_timeout_ms
Description Read operation timeout time period, for internal communication only, not for the entire operation, in milliseconds
Type Int32
Default 30000
Effective After restart system
  • write_operation_timeout_ms
Name write_operation_timeout_ms
Description The write operation timeout period, for internal communication only, not for the entire operation, in milliseconds
Type Int32
Default 30000
Effective After restart system
  • min_num_of_logs_in_mem
Name min_num_of_logs_in_mem
Description The minimum number of committed logs in memory, after each log deletion, at most such number of logs will remain in memory. Increasing the number will reduce the chance to use snapshot in catch-ups, but will also increase the memory footprint
Type Int32
Default 100
Effective After restart system
  • max_num_of_logs_in_mem
Name max_num_of_logs_in_mem
Description Maximum number of committed logs in memory, when reached, a log deletion will be triggered. Increasing the number will reduce the chance to use snapshot in catch-ups, but will also increase memory footprint
Type Int32
Default 1000
Effective After restart system
  • log_deletion_check_interval_second
Name log_deletion_check_interval_second
Description The interval for checking and deleting the committed log task, which removes oldest in-memory committed logs when their size exceeds min_num_of_logs_in_mem , in seconds
Type Int32
Default 60
Effective After restart system
  • enable_auto_create_schema
Name enable_auto_create_schema
Description Whether creating schema automatically is enabled, this will replace the one in iotdb-engine.properties
Type BOOLEAN
Default true
Effective After restart system
  • consistency_level
Name consistency_level
Description Consistency level, now three consistency levels are supported: strong, mid, and weak. Strong consistency means the server will first try to synchronize with the leader to get the newest data, if failed(timeout), directly report an error to the user; While mid consistency means the server will first try to synchronize with the leader, but if failed(timeout), it will give up and just use current data it has cached before; Weak consistency does not synchronize with the leader and simply use the local data
Type strong, mid, weak
Default mid
Effective After restart system
  • is_enable_raft_log_persistence
Name is_enable_raft_log_persistence
Description Whether to enable raft log persistence
Type BOOLEAN
Default true
Effective After restart system

Enable GC log

GC log is off by default. For performance tuning, you may want to collect the GC info.

To enable GC log, just add a parameter printgc when you start the server.

1. nohup sbin/start-node.sh printgc >/dev/null 2>&1 &

Or

1. sbin\start-node.bat printgc

GC log is stored at IOTDB_HOME/logs/gc.log.