BITCOIND(1)

NAME
bitcoind - manual page for bitcoind v27.0.0

SYNOPSIS
bitcoind [options] Start Bitcoin Core

DESCRIPTION
Bitcoin Core version v27.0.0

OPTIONS

-?

    Print this help message and exit

-alertnotify=<cmd>

    Execute command when an alert is raised (%s in cmd is replaced by message)

-allowignoredconf

    For backwards compatibility, treat an unused bitcoin.conf file in the datadir as a warning, not an error.

-assumevalid=<hex>

    If this block is in the chain assume that it and its ancestors are valid and potentially skip their script verification (0 to verify all, default: 000000000000000000026811d149d4d261995ec5b3f64f439a0a10e1a464af9a, testnet: 000000000001323071f38f21ea5aae529ece491eadaccce506a59bcc2d968917, signet: 0000000870f15246ba23c16e370a7ffb1fc8a3dcf8cb4492882ed4b0e3d4cd26)

-blockfilterindex=<type>

    Maintain an index of compact filters by block (default: 0, values: basic). If <type> is not supplied or if <type> = 1, indexes for all known types are enabled.

-blocknotify=<cmd>

    Execute command when the best block changes (%s in cmd is replaced by block hash)

-blockreconstructionextratxn=<n>

    Extra transactions to keep in memory for compact block reconstructions (default: 100)

-blocksdir=<dir>

    Specify directory to hold blocks subdirectory for *.dat files (default: <datadir>)

-blocksonly

    Whether to reject transactions from network peers. Automatic broadcast and rebroadcast of any transactions from inbound peers is disabled, unless the peer has the 'forcerelay' permission. RPC transactions are not affected. (default: 0)

-coinstatsindex

    Maintain coinstats index used by the gettxoutsetinfo RPC (default: 0)

-conf=<file>

    Specify path to read-only configuration file. Relative paths will be prefixed by datadir location (only useable from command line, not configuration file) (default: bitcoin.conf)

-daemon

    Run in the background as a daemon and accept commands (default: 0)

-daemonwait

    Wait for initialization to be finished before exiting. This implies -daemon (default: 0)

-datadir=<dir>

    Specify data directory

-dbcache=<n>

    Maximum database cache size <n> MiB (4 to 16384, default: 450). In addition, unused mempool memory is shared for this cache (see -maxmempool).

-debuglogfile=<file>

    Specify location of debug log file (default: debug.log). Relative paths will be prefixed by a net-specific datadir location. Pass -nodebuglogfile to disable writing the log to a file.

-includeconf=<file>

    Specify additional configuration file, relative to the -datadir path (only useable from configuration file, not command line)

-loadblock=<file>

    Imports blocks from external file on startup

-maxmempool=<n>

    Keep the transaction memory pool below <n> megabytes (default: 300)

-maxorphantx=<n>

    Keep at most <n> unconnectable transactions in memory (default: 100)

-mempoolexpiry=<n>

    Do not keep transactions in the mempool longer than <n> hours (default: 336)

-par=<n>

    Set the number of script verification threads (0 = auto, up to 15, <0 = leave that many cores free, default: 0)

-persistmempool

    Whether to save the mempool on shutdown and load on restart (default: 1)

-persistmempoolv1

    Whether a mempool.dat file created by -persistmempool or the savemempool RPC will be written in the legacy format (version 1) or the current format (version 2). This temporary option will be removed in the future. (default: 0)

-pid=<file>

    Specify pid file. Relative paths will be prefixed by a net-specific datadir location. (default: bitcoind.pid)

-prune=<n>

    Reduce storage requirements by enabling pruning (deleting) of old blocks. This allows the pruneblockchain RPC to be called to delete specific blocks and enables automatic pruning of old blocks if a target size in MiB is provided. This mode is incompatible with -txindex. Warning: Reverting this setting requires re-downloading the entire blockchain. (default: 0 = disable pruning blocks, 1 = allow manual pruning via RPC, >=550 = automatically prune block files to stay under the specified target size in MiB)

-reindex

    If enabled, wipe chain state and block index, and rebuild them from blk*.dat files on disk. Also wipe and rebuild other optional indexes that are active. If an assumeutxo snapshot was loaded, its chainstate will be wiped as well. The snapshot can then be reloaded via RPC.

-reindex-chainstate

    If enabled, wipe chain state, and rebuild it from blk*.dat files on disk. If an assumeutxo snapshot was loaded, its chainstate will be wiped as well. The snapshot can then be reloaded via RPC.

-settings=<file>

    Specify path to dynamic settings data file. Can be disabled with -nosettings. File is written at runtime and not meant to be edited by users (use bitcoin.conf instead for custom settings). Relative paths will be prefixed by datadir location. (default: settings.json)

-shutdownnotify=<cmd>

    Execute command immediately before beginning shutdown. The need for shutdown may be urgent, so be careful not to delay it long (if the command doesn't require interaction with the server, consider having it fork into the background).

-startupnotify=<cmd>

    Execute command on startup.

-txindex

    Maintain a full transaction index, used by the getrawtransaction rpc call (default: 0)

-version

    Print version and exit

Connection options:

-addnode=<ip>

    Add a node to connect to and attempt to keep the connection open (see the addnode RPC help for more info). This option can be specified multiple times to add multiple nodes; connections are limited to 8 at a time and are counted separately from the -maxconnections limit.

-asmap=<file>

    Specify asn mapping used for bucketing of the peers (default: ip_asn.map). Relative paths will be prefixed by the net-specific datadir location.

-bantime=<n>

    Default duration (in seconds) of manually configured bans (default: 86400)

-bind=<addr>[:<port>][=onion]

    Bind to given address and always listen on it (default: 0.0.0.0). Use [host]:port notation for IPv6. Append =onion to tag any incoming connections to that address and port as incoming Tor connections (default: 127.0.0.1:8334=onion, testnet: 127.0.0.1:18334=onion, signet: 127.0.0.1:38334=onion, regtest: 127.0.0.1:18445=onion)

-cjdnsreachable

    If set, then this host is configured for CJDNS (connecting to fc00::/8 addresses would lead us to the CJDNS network, see doc/cjdns.md) (default: 0)

-connect=<ip>

    Connect only to the specified node; -noconnect disables automatic connections (the rules for this peer are the same as for -addnode). This option can be specified multiple times to connect to multiple nodes.

-discover

    Discover own IP addresses (default: 1 when listening and no -externalip or -proxy)

-dns

    Allow DNS lookups for -addnode, -seednode and -connect (default: 1)

-dnsseed

    Query for peer addresses via DNS lookup, if low on addresses (default: 1 unless -connect used or -maxconnections=0)

-externalip=<ip>

    Specify your own public address

-fixedseeds

    Allow fixed seeds if DNS seeds don't provide peers (default: 1)

-forcednsseed

    Always query for peer addresses via DNS lookup (default: 0)

-i2pacceptincoming

    Whether to accept inbound I2P connections (default: 1). Ignored if -i2psam is not set. Listening for inbound I2P connections is done through the SAM proxy, not by binding to a local address and port.

-i2psam=<ip:port>

    I2P SAM proxy to reach I2P peers and accept I2P connections (default: none)

-listen

    Accept connections from outside (default: 1 if no -proxy, -connect or -maxconnections=0)

-listenonion

    Automatically create Tor onion service (default: 1)

-maxconnections=<n>

    Maintain at most <n> automatic connections to peers (default: 125). This limit does not apply to connections manually added via -addnode or the addnode RPC, which have a separate limit of 8.

-maxreceivebuffer=<n>

    Maximum per-connection receive buffer, <n>*1000 bytes (default: 5000)

-maxsendbuffer=<n>

    Maximum per-connection memory usage for the send buffer, <n>*1000 bytes (default: 1000)

-maxtimeadjustment

    Maximum allowed median peer time offset adjustment. Local perspective of time may be influenced by outbound peers forward or backward by this amount (default: 4200 seconds).

-maxuploadtarget=<n>

    Tries to keep outbound traffic under the given target per 24h. Limit does not apply to peers with 'download' permission or blocks created within past week. 0 = no limit (default: 0M). Optional suffix units [k|K|m|M|g|G|t|T] (default: M). Lowercase is 1000 base while uppercase is 1024 base

-natpmp

    Use NAT-PMP to map the listening port (default: 0)

-networkactive

    Enable all P2P network activity (default: 1). Can be changed by the setnetworkactive RPC command

-onion=<ip:port>

    Use separate SOCKS5 proxy to reach peers via Tor onion services, set -noonion to disable (default: -proxy)

-onlynet=<net>

    Make automatic outbound connections only to network <net> (ipv4, ipv6, onion, i2p, cjdns). Inbound and manual connections are not affected by this option. It can be specified multiple times to allow multiple networks.

-peerblockfilters

    Serve compact block filters to peers per BIP 157 (default: 0)

-peerbloomfilters

    Support filtering of blocks and transaction with bloom filters (default: 0)

-port=<port>

    Listen for connections on <port>. Nodes not using the default ports (default: 8333, testnet: 18333, signet: 38333, regtest: 18444) are unlikely to get incoming connections. Not relevant for I2P (see doc/i2p.md).

-proxy=<ip:port>

    Connect through SOCKS5 proxy, set -noproxy to disable (default: disabled)

-proxyrandomize

    Randomize credentials for every proxy connection. This enables Tor stream isolation (default: 1)

-seednode=<ip>

    Connect to a node to retrieve peer addresses, and disconnect. This option can be specified multiple times to connect to multiple nodes.

-timeout=<n>

    Specify socket connection timeout in milliseconds. If an initial attempt to connect is unsuccessful after this amount of time, drop it (minimum: 1, default: 5000)

-torcontrol=<ip>:<port>

    Tor control host and port to use if onion listening enabled (default: 127.0.0.1:9051). If no port is specified, the default port of 9051 will be used.

-torpassword=<pass>

    Tor control port password (default: empty)

-upnp

    Use UPnP to map the listening port (default: 1 when listening and no -proxy)

-v2transport

    Support v2 transport (default: 1)

-whitebind=<[permissions@]addr>

    Bind to the given address and add permission flags to the peers connecting to it. Use [host]:port notation for IPv6. Allowed permissions: bloomfilter (allow requesting BIP37 filtered blocks and transactions), noban (do not ban for misbehavior; implies download), forcerelay (relay transactions that are already in the mempool; implies relay), relay (relay even in -blocksonly mode, and unlimited transaction announcements), mempool (allow requesting BIP35 mempool contents), download (allow getheaders during IBD, no disconnect after maxuploadtarget limit), addr (responses to GETADDR avoid hitting the cache and contain random records with the most up-to-date info). Specify multiple permissions separated by commas (default: download,noban,mempool,relay). Can be specified multiple times.

-whitelist=<[permissions@]IP address or network>

    Add permission flags to the peers connecting from the given IP address (e.g. 1.2.3.4) or CIDR-notated network (e.g. 1.2.3.0/24). Uses the same permissions as -whitebind. Can be specified multiple times.

Wallet options:

-addresstype

    What type of addresses to use ("legacy", "p2sh-segwit", "bech32", or "bech32m", default: "bech32")

-avoidpartialspends

    Group outputs by address, selecting many (possibly all) or none, instead of selecting on a per-output basis. Privacy is improved as addresses are mostly swept with fewer transactions and outputs are aggregated in clean change addresses. It may result in higher fees due to less optimal coin selection caused by this added limitation and possibly a larger-than-necessary number of inputs being used. Always enabled for wallets with "avoid_reuse" enabled, otherwise default: 0.

-changetype

    What type of change to use ("legacy", "p2sh-segwit", "bech32", or "bech32m"). Default is "legacy" when -addresstype=legacy, else it is an implementation detail.

-consolidatefeerate=<amt>

    The maximum feerate (in BTC/kvB) at which transaction building may use more inputs than strictly necessary so that the wallet's UTXO pool can be reduced (default: 0.0001).

-disablewallet

    Do not load the wallet and disable wallet RPC calls

-discardfee=<amt>

    The fee rate (in BTC/kvB) that indicates your tolerance for discarding change by adding it to the fee (default: 0.0001). Note: An output is discarded if it is dust at this rate, but we will always discard up to the dust relay fee and a discard fee above that is limited by the fee estimate for the longest target

-fallbackfee=<amt>

    A fee rate (in BTC/kvB) that will be used when fee estimation has insufficient data. 0 to entirely disable the fallbackfee feature. (default: 0.00)

-keypool=<n>

    Set key pool size to <n> (default: 1000). Warning: Smaller sizes may increase the risk of losing funds when restoring from an old backup, if none of the addresses in the original keypool have been used.

-maxapsfee=<n>

    Spend up to this amount in additional (absolute) fees (in BTC) if it allows the use of partial spend avoidance (default: 0.00)

-mintxfee=<amt>

    Fee rates (in BTC/kvB) smaller than this are considered zero fee for transaction creation (default: 0.00001)

-paytxfee=<amt>

    Fee rate (in BTC/kvB) to add to transactions you send (default: 0.00)

-signer=<cmd>

    External signing tool, see doc/external-signer.md

-spendzeroconfchange

    Spend unconfirmed change when sending transactions (default: 1)

-txconfirmtarget=<n>

    If paytxfee is not set, include enough fee so transactions begin confirmation on average within n blocks (default: 6)

-wallet=<path>

    Specify wallet path to load at startup. Can be used multiple times to load multiple wallets. Path is to a directory containing wallet data and log files. If the path is not absolute, it is interpreted relative to <walletdir>. This only loads existing wallets and does not create new ones. For backwards compatibility this also accepts names of existing top-level data files in <walletdir>.

-walletbroadcast

    Make the wallet broadcast transactions (default: 1)

-walletdir=<dir>

    Specify directory to hold wallets (default: <datadir>/wallets if it exists, otherwise <datadir>)

-walletnotify=<cmd>

    Execute command when a wallet transaction changes. %s in cmd is replaced by TxID, %w is replaced by wallet name, %b is replaced by the hash of the block including the transaction (set to 'unconfirmed' if the transaction is not included) and %h is replaced by the block height (-1 if not included). %w is not currently implemented on windows. On systems where %w is supported, it should NOT be quoted because this would break shell escaping used to invoke the command.

-walletrbf

    Send transactions with full-RBF opt-in enabled (RPC only, default: 1)

ZeroMQ notification options:

-zmqpubhashblock=<address>

    Enable publish hash block in <address>

-zmqpubhashblockhwm=<n>

    Set publish hash block outbound message high water mark (default: 1000)

-zmqpubhashtx=<address>

    Enable publish hash transaction in <address>

-zmqpubhashtxhwm=<n>

    Set publish hash transaction outbound message high water mark (default: 1000)

-zmqpubrawblock=<address>

    Enable publish raw block in <address>

-zmqpubrawblockhwm=<n>

    Set publish raw block outbound message high water mark (default: 1000)

-zmqpubrawtx=<address>

    Enable publish raw transaction in <address>

-zmqpubrawtxhwm=<n>

    Set publish raw transaction outbound message high water mark (default: 1000)

-zmqpubsequence=<address>

    Enable publish hash block and tx sequence in <address>

-zmqpubsequencehwm=<n>

    Set publish hash sequence message high water mark (default: 1000)

Debugging/Testing options:

-debug=<category>

    Output debug and trace logging (default: -nodebug, supplying <category> is optional). If <category> is not supplied or if <category> = 1, output all debug and trace logging. <category> can be: addrman, bench, blockstorage, cmpctblock, coindb, estimatefee, http, i2p, ipc, leveldb, libevent, mempool, mempoolrej, net, proxy, prune, qt, rand, reindex, rpc, scan, selectcoins, tor, txpackages, txreconciliation, util, validation, walletdb, zmq. This option can be specified multiple times to output multiple categories.

-debugexclude=<category>

    Exclude debug and trace logging for a category. Can be used in conjunction with -debug=1 to output debug and trace logging for all categories except the specified category. This option can be specified multiple times to exclude multiple categories.

-help-debug

    Print help message with debugging options and exit

-logips

    Include IP addresses in debug output (default: 0)

-loglevelalways

    Always prepend a category and level (default: 0)

-logsourcelocations

    Prepend debug output with name of the originating source location (source file, line number and function name) (default: 0)

-logthreadnames

    Prepend debug output with name of the originating thread (only available on platforms supporting thread_local) (default: 0)

-logtimestamps

    Prepend debug output with timestamp (default: 1)

-maxtxfee=<amt>

    Maximum total fees (in BTC) to use in a single wallet transaction; setting this too low may abort large transactions (default: 0.10)

-printtoconsole

    Send trace/debug info to console (default: 1 when no -daemon. To disable logging to file, set -nodebuglogfile)

-shrinkdebugfile

    Shrink debug.log file on client startup (default: 1 when no -debug)

-uacomment=<cmt>

    Append comment to the user agent string

Chain selection options:

-chain=<chain>

    Use the chain <chain> (default: main). Allowed values: main, test, signet, regtest

-signet

    Use the signet chain. Equivalent to -chain=signet. Note that the network is defined by the -signetchallenge parameter

-signetchallenge

    Blocks must satisfy the given script to be considered valid (only for signet networks; defaults to the global default signet test network challenge)

-signetseednode

    Specify a seed node for the signet network, in the hostname[:port] format, e.g. sig.net:1234 (may be used multiple times to specify multiple seed nodes; defaults to the global default signet test network seed node(s))

-testnet

    Use the test chain. Equivalent to -chain=test.

Node relay options:

-bytespersigop

    Equivalent bytes per sigop in transactions for relay and mining (default: 20)

-datacarrier

    Relay and mine data carrier transactions (default: 1)

-datacarriersize

    Relay and mine transactions whose data-carrying raw scriptPubKey is of this size or less (default: 83)

-mempoolfullrbf

    Accept transaction replace-by-fee without requiring replaceability signaling (default: 0)

-minrelaytxfee=<amt>

    Fees (in BTC/kvB) smaller than this are considered zero fee for relaying, mining and transaction creation (default: 0.00001)

-permitbaremultisig

    Relay non-P2SH multisig (default: 1)

-whitelistforcerelay

    Add 'forcerelay' permission to whitelisted inbound peers with default permissions. This will relay transactions even if the transactions were already in the mempool. (default: 0)

-whitelistrelay

    Add 'relay' permission to whitelisted inbound peers with default permissions. This will accept relayed transactions even when not relaying transactions (default: 1)

Block creation options:

-blockmaxweight=<n>

    Set maximum BIP141 block weight (default: 3996000)

-blockmintxfee=<amt>

    Set lowest fee rate (in BTC/kvB) for transactions to be included in block creation. (default: 0.00001)

RPC server options:

-rest

    Accept public REST requests (default: 0)

-rpcallowip=<ip>

    Allow JSON-RPC connections from specified source. Valid values for <ip> are a single IP (e.g. 1.2.3.4), a network/netmask (e.g. 1.2.3.4/255.255.255.0), a network/CIDR (e.g. 1.2.3.4/24), all ipv4 (0.0.0.0/0), or all ipv6 (::/0). This option can be specified multiple times

-rpcauth=<userpw>

    Username and HMAC-SHA-256 hashed password for JSON-RPC connections. The field <userpw> comes in the format: <USERNAME>:<SALT>$<HASH>. A canonical python script is included in share/rpcauth. The client then connects normally using the rpcuser=<USERNAME>/rpcpassword=<PASSWORD> pair of arguments. This option can be specified multiple times

-rpcbind=<addr>[:port]

    Bind to given address to listen for JSON-RPC connections. Do not expose the RPC server to untrusted networks such as the public internet! This option is ignored unless -rpcallowip is also passed. Port is optional and overrides -rpcport. Use [host]:port notation for IPv6. This option can be specified multiple times (default: 127.0.0.1 and ::1 i.e., localhost)

-rpccookiefile=<loc>

    Location of the auth cookie. Relative paths will be prefixed by a net-specific datadir location. (default: data dir)

-rpcpassword=<pw>

    Password for JSON-RPC connections

-rpcport=<port>

    Listen for JSON-RPC connections on <port> (default: 8332, testnet: 18332, signet: 38332, regtest: 18443)

-rpcthreads=<n>

    Set the number of threads to service RPC calls (default: 4)

-rpcuser=<user>

    Username for JSON-RPC connections

-rpcwhitelist=<whitelist>

    Set a whitelist to filter incoming RPC calls for a specific user. The field <whitelist> comes in the format: <USERNAME>:<rpc 1>,<rpc 2>,...,<rpc n>. If multiple whitelists are set for a given user, they are set-intersected. See -rpcwhitelistdefault documentation for information on default whitelist behavior.

-rpcwhitelistdefault

    Sets default behavior for rpc whitelisting. Unless rpcwhitelistdefault is set to 0, if any -rpcwhitelist is set, the rpc server acts as if all rpc users are subject to empty-unless-otherwise-specified whitelists. If rpcwhitelistdefault is set to 1 and no -rpcwhitelist is set, rpc server acts as if all rpc users are subject to empty whitelists.

-server

    Accept command line and JSON-RPC commands

COPYRIGHT
Copyright (C) 2009-2024 The Bitcoin Core developers Please contribute if you find Bitcoin Core useful. Visit <https://bitcoincore.org/> for further information about the software. The source code is available from <https://github.com/bitcoin/bitcoin>. This is experimental software. Distributed under the MIT software license, see the accompanying file COPYING or <https://opensource.org/licenses/MIT>