Configuration File

    Use the or --stan_config command line parameter to specify the file to use.

    For the embedded NATS Server, you can use another configuration file and pass it to the Streaming Server using -c or --config command line parameters.

    Since most options do not overlap, it is possible to combine all options into a single file and specify this file using either the -sc or -c command line parameter.

    However, the option named tls is common to NATS Server and NATS Streaming Server. If you plan to use a single configuration file and configure TLS, you should have all the streaming configuration included in a streaming map. This is actually a good practice regardless if you use TLS or not, to protect against possible addition of new options in NATS Server that would conflict with the names of NATS Streaming options.

    For instance, you could use a single configuration file with such content:

    Note the order in which options are applied during the start of a NATS Streaming server:

    1. Start with some reasonable default options.

    2. If a configuration file is specified, override those options

      with all options defined in the file. This includes options that are defined

      but have no value specified. In this case, the zero value for the type of the

      option will be used.

    In general the configuration parameters are the same as the command line arguments. Below is the list of NATS Streaming parameters:

    Note: You may need to scroll horizontally to see all columns.

    Notes:

    (1) The seed file contains the NKey seed from which the Streaming server can extract the public key and the private key used to sign the nonce sent by the NATS Server when accepting connections from the Streaming server. The file is read during the connection process, the key is used to sign but then wiped from memory. The file must contain the seed file with the following format:

    Note that the Streaming Server uses a connection to a NATS Server, and so the NATS Streaming TLS Configuration is in fact a client-side TLS configuration.

    Parameter Meaning Possible Values Usage Example Default Value Since
    client_cert Client key for the streaming server File path client_cert: "/path/to/client/cert_file" N/A All
    client_key Client certificate for the streaming server File path client_key: "/path/to/client/key_file" N/A All
    client_ca Client certificate CA for the streaming server File path client_ca: "/path/to/client/ca_file" N/A All
    server_name Expected hostname returned in the NATS Server certificate String server_name: "theserverhostname" N/A v0.17.0
    insecure Skips the NATS server’s certificate chain and host name verification. Should not be used in production true or false insecure: true false v0.17.0

    Store Limits Configuration

    For a given channel, the possible parameters are:

    Parameter Meaning Possible Values Usage Example Default Value Since
    max_subs Maximum number of subscriptions per channel, 0 means unlimited Number >= 0 max_subs: 100 Inherit from global settings All
    max_msgs Maximum number of messages per channel, 0 means unlimited Number >= 0 max_msgs: 10000 Inherit from global settings All
    max_bytes Total size of messages per channel, 0 means unlimited Bytes max_bytes: 1GB Inherit from global settings All
    max_age How long messages can stay in the log Duration max_age: "24h" Inherit from global settings All
    max_inactivity How long without any subscription and any new message before a channel can be automatically deleted Duration max_inactivity: "24h" Inherit from global settings v0.9.0

    File Options Configuration

    Parameter Meaning Possible Values Usage Example Default Value Since
    node_id ID of the node within the cluster if there is no stored ID String (no whitespace) node_id: "node-a" N/A v0.9.0
    bootstrap Bootstrap the cluster if there is no existing state by electing self as leader true or false bootstrap: true false v0.9.0
    peers List of cluster peer node IDs to bootstrap cluster state List of node IDs peers: ["node-b", "node-c"] N/A v0.9.0
    log_path Directory to store log replication data File path log_path: "/path/to/storage" N/A v0.9.0
    log_cache_size Number of log entries to cache in memory to reduce disk IO Number >= 0 log_cache_size: 1024 512 v0.9.0
    log_snapshots Number of log snapshots to retain Number >= 0 log_snapshots: 1 2 v0.9.0
    trailing_logs Number of log entries to leave after a snapshot and compaction Number >= 0 trailing_logs: 256 10240 v0.9.0
    sync Do a file sync after every write to the replication log and message store true or false sync: true false v0.9.0
    raft_logging Enable logging from the Raft library (disabled by default) true or false raft_logging: true false v0.9.0
    raft_heartbeat_timeout Specifies the time in follower state without a leader before attempting an election Duration raft_heartbeat_timeout: "2s" 2s v0.11.2
    raft_election_timeout Specifies the time in candidate state without a leader before attempting an election Duration raft_election_timeout: "2s" 2s v0.11.2
    raft_lease_timeout Specifies how long a leader waits without being able to contact a quorum of nodes before stepping down as leader Duration raft_lease_timeout: "1s" 1s v0.11.2
    raft_commit_timeout Specifies the time without an Apply() operation before sending an heartbeat to ensure timely commit. Due to random staggering, may be delayed as much as 2x this value Duration raft_commit_timeout: "100ms" 100ms v0.11.2
    proceed_on_restore_failure Allow a non leader node to proceed with restore failures, do not use unless you understand the risks! true or false proceed_on_restore_failure: true false v0.17.0
    allow_add_remove_node Enable the ability to send NATS requests to the leader to add/remove cluster nodes true or false allow_add_remove_node: true false v0.19.0
    bolt_free_list_sync Causes the RAFT log to synchronize the free list on write operations. Reduces performance at runtime, but makes the recovery faster true or false bolt_free_list_sync: true false v0.21.0
    bolt_free_list_map Sets the backend freelist type to use a map instead of the default array type. Improves performance for large RAFT logs, with fragmented free list true or false bolt_free_list_map: true false v0.21.0
    nodes_connections Enable creation of dedicated NATS connections to communicate with other nodes true or false nodes_connections: true false v0.21.0

    SQL Options Configuration