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Configuration File Locations

The node uses the config.json and rpc_config.json files found in the following locations:

OS Location
Windows C:\Users\<user>\AppData\Local\Nano\
OSX /Users/<user>/Library/Nano/
Linux /home/<user>/Nano/

Backups of config files on upgrade

In versions 19.0+ when the node is upgraded between releases, including any beta releases, all config files will be backed up prior to the upgrade in the same folder for easy recovery if needed.


This is the main configuration file for controlling node behavior. Below is an example file with most option and further details on specific configuration items.

Example file

    "version": "(int)", // Wallet version
    "wallet": "(string)", // Default wallet to load on boot (only for GUI wallet)
    "account": "(string)", // Default account to load on boot (only for GUI wallet)
    "node": {
        "version": "(int)", // Node version
        "peering_port": "7075", // Default node port
        "bootstrap_fraction_numerator": "1", 
        "enable_voting": "false", // Enable or disable voting for blocks. If disabled, saves some resources
        "receive_minimum": "1000000000000000000000000", // Minimum import receivable, default 1 Rai
        "logging": {
            "ledger": "false", // Track incoming blocks
            "ledger_duplicate": "false",
            "network": "true", // Track general network info like forks
            "network_timeout": "false", // Track TCP socket disconnections due to timeout
            "network_message": "false",
            "network_publish": "false", // Track blocks you publish to
            "network_packet": "false", // Track packets origin
            "network_keepalive": "false", // Track keepalive messages
            "network_node_id_handshake": "false", // Track node_id messages
            "node_lifetime_tracing": "false",
            "insufficient_work": "true",
            "bulk_pull": "false", // Bootstrap related logging
            "work_generation_time": "true",
            "log_to_cerr": "false",
            "max_size": "16777216", // Max size of logs before old files deletion. Default is 16MB 
            "rotation_size": "4194304", // Size of Log File before rotation in bytes, Default is 4MB 
            "version": "(int)", // Logging config version
            "vote": "false", // Track voting activities
            "flush": "true",  // Setting this to false gives better performance, but may lose entries on crashes.
            "upnp_details": "false", // Determines if upnp discovery details are logged (default off to avoid sharing device info when shipping logs)
            "timing": "false", // Logs durations of key functions, such as batch verification, etc.
            "log_ipc": "true", // Logging of IPC related messages
            "min_time_between_output": "5", // Minimum time between log calls, in ms
            "single_line_record": "false" // Log each record in single line (including block content & election results with votes)
        "vote_minimum": "1000000000000000000000000000000000",// Prevents voting if delegated weight is under this threshold
        "work_peers": "", // Delegate a node your hash work, you need to get RPC access to that node
        "preconfigured_peers": [ // List of defaults peers to connect on boot
        "preconfigured_representatives": [ // List of defaults representatives, which you delegate voting weight, of your wallet
        "online_weight_minimum": "60000000000000000000000000000000000000", // Online weight minimum required to confirm block
        "online_weight_quorum": "50", // Percentage of votes required to rollback blocks
        "password_fanout": "1024", 
        "io_threads": "4", 
        "work_threads": "4", // PoW work threads. By default all available CPU threads, set lower value for 24/7 services
        "callback_address": "::ffff:", // Callback IP address, in sample IPv4 localhost
        "callback_port": "17076", // Callback port
        "callback_target": "/", // Callback target, in sample root of callback listening server
        "bootstrap_connections": "16", // Multi-connection bootstrap. Should be a power of 2.
        "bootstrap_connections_max": "4", // Allowed incoming bootstrap connections count. Lower value save IOPS & bandwidth. 64 recommended for high-end fast nodes, 0 for HDD home users,
        "lmdb_max_dbs": "128", // Maximum open DBs (MAX_DBS, increase default if more than 100 wallets required
        "block_processor_batch_max_time": "5000", // Number of milliseconds the block processor works at a time
        "allow_local_peers": "false", // To allow local host peering
        "signature_checker_threads": "1", // Number of threads to use for verifying signatures
        "unchecked_cutoff_time": "14400", // Number of seconds unchecked entry survives before being cleaned
        "tcp_io_timeout": "15", // Timeout in seconds for TCP connect-, read- and write operations
        "pow_sleep_interval": "0", // The amount to sleep after each batch of POW calculations. Reduces max CPU usage at the expensive of a longer workgeneration time.
        "external_address": "::",
        "external_port": "0",
        "tcp_incoming_connections_max": "1024", // Allowed incoming TCP connections count
        "websocket": {
            "enable": "false",
            "address": "::1", // Default IPv6 address to listen on. If using Docker, change address to ::ffff: to listen on all interfaces within the container.
            "port": "7078"
        "ipc": { // For more details about these options see the IPC section below
            "tcp": {
                "enable": "false",
                "port": "7077",
                "io_timeout": "15"
            "local": {
                "version": "1",
                "enable": "false",
                "allow_unsafe": "false",
                "path": "\/tmp\/nano",
                "io_timeout": "15"
        "diagnostics": {
                "txn_tracking": {
                    "enable": "false", // Tracks lmdb transactions
                    "min_read_txn_time": "5000", // Logs stacktrace when read transactions are held longer than this time (milliseconds)
                    "min_write_txn_time": "500", // Logs stacktrace when write transactions are held longer than this time (milliseconds)
                    "ignore_writes_below_block_processor_max_time": "true" // Ignore any block processor writes less than block_processor_max_time
        "use_memory_pools": "true", // Improve performance by using memory pools (Note: Memory allocated will be reused but never reclaimed, if having memory issues then try turning this off)
        "confirmation_history_size": "2048", // Controls confirmation history size, default setting preserves existing behavior
        "bandwidth_limit": "5242880", // Outbound voting traffic limit in bytes/sec after which messages will be dropped
        "vote_generator_delay": "100", // Delay in ms before votes are sent out to allow for better bundling of hashes in votes
        "vote_generator_threshold": "3", // Defines the point at which the node will delay sending votes for another vote_generator_delay. Allows for more hashes to be bundled under load
        "active_elections_size": "50000", // Limits number of active elections in container before dropping will be considered (other conditions must also be satisfied), minimum value allowed is 250.
        "conf_height_processor_batch_min_time": "50", // Amount of time in ms to batch setting confirmation heights for accounts during high tps to reduce write I/O bottlenecks.
        "backup_before_upgrade": "false", // Backup ledger & wallet databases before each upgrade
        "work_watcher_period": "5" // Time between checks for confirmation and re-generating higher difficulty work if unconfirmed, for blocks in the work watcher
    "rpc_enable": "true", // Enable (in-process or child process) or disable RPC. Out of process rpc servers can still be used if launched manually.
    "rpc": {
        "enable_sign_hash": "true",
        "max_work_generate_difficulty": "ffffffffc0000000", // Maximum difficulty allowed on work_generate RPC requests, corresponds to 256x multiplier
        "version": "1",
        "child_process": {
            "enable": "false", // Whether the rpc server is run as a child process rather than in-process
            "rpc_path": "C:\\Users\\Wesley\\Documents\\raiblocks\\build\\Debug\\nano_rpc.exe", // The nano_rpc executable to run if enabled (Windows example).
    "opencl_enable": "false", // Enable GPU hashing
    "opencl": {
        "platform": "0", // Platform ID
        "device": "0", // Device ID
        "threads": "1048576" 

Configuration options


As of V18.0, newly setup nodes will have voting disabled by default. In order to participate in network consensus, this value must be updated to enable voting and the node restarted.

"enable_voting": "true"


As of V18.0, nodes with weight delegated to them under this value in their config will not vote, regardless of the enable_voting flag setting. In order for a node to vote, this value must be lower than the weight delegated to the representative account setup on the node.

"vote_minimum": "1000000000000000000000000000000000"


Used when offloading work generation to another node or service. Format must be ipv6, preceded by ::ffff: if ipv4. Hostnames are not allowed at this time. Calls are made to the ip:port designated using the standard RPC format work_generate.

"work_peers": [


To enable GPU acceleration for PoW, set "opencl_enable" to "true". Other OpenCL parameters may need to be adjusted depending on the desired setup (see example config.json file above).


On startup, the node will generate configuration options for IPC, one entry for each transport. By default, IPC is disabled.

"ipc": {
   "tcp": {
       "enable": "false",
       "port": "7077",
       "io_timeout": "15" // seconds
   "local": {
       "enable": "false",
       "path": "\/tmp\/nano",
       "io_timeout": "15" // seconds

Each transport also supports an experimental "io_threads" configuration value. If not present (default), the node's IO event loop will be used. If a value is present, a separate event loop with N threads will be created for the transport. For certain transports, this may scale better on some systems.

Because the only IPC encoding is currently "legacy RPC", the RPC config options like "enable_control" still applies.

For details about using the IPC setup, see the IPC Integration Guide.


Available in Version 19.0+ only

"node": {
    "websocket": {
        "enable": "true",
        "address": "::1",
        "port": "7078"

With the above configuration, localhost clients should connect to ws://[::1]:7078. For details on how to integrate using websockets, see the Websocket Support section of the Integration Guides.

HTTP callback

"node": {
    "callback_address": "::ffff:",
    "callback_port": "17076",
    "callback_target": "/"

JSON POST requests with every confirmed block are sent to the callback server as defined in the config values above: http://callback_address:callback_port<callback_target>. Callback target should include a leading slash.

For details on how to integrate using the HTTP callback, see the HTTP Callback section of the Integration Guides.


When possible, using the websockets is recommended as it provides more efficiency, more options for types of information to receive and better control over the volume of notifications with filtering.


This is the configuration that controls how the RPC server connects and behaves when communicating with the node.

Available in Version 19.0+ only

Example file

    "address": "::ffff:", // Allowed IP for RPC connection
    "port": "7076", // Default RPC port
    "enable_control": "true", // Enable particular RPC command like: send, account_create, etc...
    "max_json_depth": "20", // prevent JSON overflow. Default recommended
    "version": "1",
    "max_request_size": "33554432",
    "process": {
        "io_threads": "8", // Number of threads listening to RPC requests 
        "ipc_port": "46000", // Must match port in ipc -> tcp of node config file
        "num_ipc_connections": "8" // Max number of connections with nano_node (io_threads in config.json should be at least this number)

More details about the RPC setup can be found in the Running Nano as a service guide.

Warning - Multiple Node Setups

Never use the same seed on multiple running nano_node instances at the same time.

  • Multiple nano_nodes using the same seed can result in network race conditions that degrade performance for your personal accounts.
  • In addition, Publishing transactions from two nodes with the same account at the same time may cause an account fork which requires a slower representative voting process.
  • Similarly, if you are running a representative account on multiple nodes, they may publish conflicting votes, causing your representative to be ignored by the network.
  • Performance degradation in enterprise environments may be significant.

Network Details

Port Type Default Details
7075 UDP Enabled
  • Primary node activity port
  • Port configurable in config.json:node/peering_port
  • Binds to all adapters, unicast
  • Contents: Raw nano protocol datagrams
  • All standard ledger activity goes through this port
  • If blocked the node will not function
7075 TCP Enabled
  • Node bootstrapping server
  • Share port configuration in config.json:node/peering_port
  • Binds to all adapters, unicast
  • Contents: Raw nano protocol stream
  • Transmits the ledger to new nodes in bulk
  • If blocked other nodes will not be able retrieve the ledger from this node
7076 TCP Disabled
  • RPC server
  • Port configurable in rpc_config.json:rpc/port
  • Enable in config.json:rpc_enable or by starting nano_rpc manually
  • Binds to localhost by default for security reasons, configurable in rpc_config.json:rpc/address, unicast
  • Contents: Unencrypted HTTP requests containing JSON object bodies
  • Allows the node to be queried or controlled through HTTP requests
  • If blocked the node will not be able to be queried or controlled by HTTP