Running Bitcoin

There are two variations of the official bitcoin program available; one with a graphical user interface (usually referred to as just “Bitcoin”), and a 'headless' version (called bitcoind). They are completely compatible with each other, and take the same command-line arguments, read the same configuration file, and read and write the same data files. You can run one copy of either Bitcoin or bitcoind on your system at a time (if you accidently try to launch another, the copy will let you know that Bitcoin or bitcoind is already running and will exit).

Command-line arguments

Give Bitcoin (or bitcoind) the -? or –help argument and it will print out a list of the most commonly used command-line arguments and then exit:

Usage:

 bitcoin [options]                     
 bitcoin [options] <command> [params]  Send command to -server or bitcoind
 bitcoin [options] help                List commands
 bitcoin [options] help <command>      Get help for a command

Options:

 -conf=<file>       Specify configuration file (default: bitcoin.conf)
 -gen               Generate coins
 -gen=0             Don't generate coins
 -min               Start minimized
 -datadir=<dir>     Specify data directory
 -proxy=<ip:port>   Connect through socks4 proxy
 -addnode=<ip>      Add a node to connect to
 -connect=<ip>      Connect only to the specified node
 -nolisten          Don't accept connections from outside
 -noupnp            Don't attempt to use UPnP to map the listening port
 -upnp              Attempt to use UPnP to map the listening port
 -paytxfee=<amt>    Fee per KB added to transactions you send
 -server            Accept command line and JSON-RPC commands
 -daemon            Run in the background as a daemon and accept commands
 -testnet           Use the test network
 -port=<port>       Connect to the Network from <port> (default: 8333; 18333 for testnet)
 -rpcuser=<user>    Username for JSON-RPC connections
 -rpcpassword=<pw>  Password for JSON-RPC connections
 -rpcport=<port>    Listen for JSON-RPC connections on <port> (default: 8332)
 -rpcallowip=<ip>   Allow JSON-RPC connections from specified IP address
 -rpcconnect=<ip>   Send commands to node running on <ip> (default: 127.0.0.1)
 -keypool=<n>       Set key pool size to <n> (default: 100)
 -rescan            Rescan the block chain for missing wallet transactions
 -rpcssl            Use OpenSSL (https) for JSON-RPC connections
 -?                 This help message

Bitcoin.conf Configuration File

All command-line options (except for -datadir and -conf) may be specified in a configuration file, and all configuration file options may also be specified on the command line. Command-line options override values set in the configuration file.

The configuration file is a list of setting=value pairs, one per line, with optional comments starting with the '#' character.

The configuration file is not automatically created; you can create it using your favorite plain-text editor. By default, Bitcoin (or bitcoind) will look for a file named 'bitcoin.conf' in the bitcoin data directory, but both the data directory and the configuration file path may be changed using the -datadir and -conf command-line arguments.

Operating System	Default bitcoin datadir	Typical path to configuration file
Windows	%APPDATA%\Bitcoin\	(XP) C:\Documents and Settings\username\Application Data\Bitcoin\bitcoin.conf (Vista, 7) C:\Users\username\AppData\Roaming\Bitcoin\bitcoin.conf
Linux	$HOME/.bitcoin/	/home/username/.bitcoin/bitcoin.conf
Mac OSX	$HOME/Library/Application Support/Bitcoin/	/Users/username/Library/Application Support/Bitcoin/bitcoin.conf

Sample Bitcoin.conf

Here is a sample bitcoin.conf file, containing every option set to its default value.

 # bitcoin.conf configuration file. Lines beginning with # are comments.
 
 
 # Network-related settings:
 
 # Run on the test network instead of the real bitcoin network.
 #testnet=1
 
 # Connect via a socks4 proxy
 #proxy=127.0.0.1:9050
 
 ##############################################################
 ##            Quick Primer on addnode vs connect            ##
 ##  Let's say for instance you use addnode=4.2.2.4          ##
 ##  addnode will connect you to and tell you about the      ##
 ##    nodes connected to 4.2.2.4.  In addition it will tell ##
 ##    the other nodes connected to it that you exist so     ##
 ##    they can connect to you.                              ##
 ##  connect will not do the above when you 'connect' to it. ##
 ##    It will *only* connect you to 4.2.2.4 and no one else.##
 ##                                                          ##
 ##  So if you're behind a firewall, or have other problems  ##
 ##  finding nodes, add some using 'addnode'.                ##
 ##                                                          ##
 ##  If you want to stay private, use 'connect' to only      ##
 ##  connect to "trusted" nodes.                             ##
 ##                                                          ##
 ##  If you run multiple nodes on a LAN, there's no need for ##
 ##  all of them to open lots of connections.  Instead       ##
 ##  'connect' them all to one node that is port forwarded   ##
 ##  and has lots of connections.                            ##
 ##       Thanks goes to [Noodle] on Freenode.               ##
 ##############################################################
 
 # Use as many addnode= settings as you like to connect to specific peers
 #addnode=69.164.218.197
 #addnode=10.0.0.2:8333
 
 # ... or use as many connect= settings as you like to connect ONLY
 # to specific peers:
 #connect=69.164.218.197
 #connect=10.0.0.1:8333
 
 # Do not use Internet Relay Chat (irc.lfnet.org #bitcoin channel) to
 # find other peers.
 #noirc=1
 
 # Maximum number of inbound+outbound connections.
 #maxconnections=
 
 
 # JSON-RPC options (for controlling a running Bitcoin/bitcoind process)
 
 # server=1 tells Bitcoin to accept JSON-RPC commands.
 #server=1
 
 # You must set rpcuser and rpcpassword to secure the JSON-RPC api
 #rpcuser=Ulysseys
 #rpcpassword=YourSuperGreatPasswordNumber_385593
 
 # How many seconds bitcoin will wait for a complete RPC HTTP request.
 # after the HTTP connection is established. 
 rpctimeout=30
 
 # By default, only RPC connections from localhost are allowed.  Specify
 # as many rpcallowip= settings as you like to allow connections from
 # other hosts (and you may use * as a wildcard character):
 #rpcallowip=10.1.1.34
 #rpcallowip=192.168.1.*
 
 # Listen for RPC connections on this TCP port:
 rpcport=8332
 
 # You can use Bitcoin or bitcoind to send commands to Bitcoin/bitcoind
 # running on another host using this option:
 rpcconnect=127.0.0.1
 
 # Use Secure Sockets Layer (also known as TLS or HTTPS) to communicate
 # with Bitcoin -server or bitcoind
 #rpcssl=1
 
 # OpenSSL settings used when rpcssl=1
 rpcsslciphers=TLSv1+HIGH:!SSLv2:!aNULL:!eNULL:!AH:!3DES:@STRENGTH
 rpcsslcertificatechainfile=server.cert
 rpcsslprivatekeyfile=server.pem
 
 
 # Miscellaneous options
 
 # Set gen=1 to attempt to generate bitcoins
 gen=0
 
 # Use SSE instructions to try to generate bitcoins faster.
 #4way=1
 
 # Pre-generate this many public/private key pairs, so wallet backups will be valid for
 # both prior transactions and several dozen future transactions.
 keypool=100
 
 # Pay an optional transaction fee every time you send bitcoins.  Transactions with fees
 # are more likely than free transactions to be included in generated blocks, so may
 # be validated sooner.
 paytxfee=0.00
 
 # Allow direct connections for the 'pay via IP address' feature.
 #allowreceivebyip=1
 
 
 # User interface options
 
 # Start Bitcoin minimized
 #min=1
 
 # Minimize to the system tray
 #minimizetotray=1

Platforms

Windows

Start automatically

To configure the Bitcoin client to start automatically:

Settings -> Options

then mark the checkbox titled:

[X] Start Bitcoin on window system startup

Generate on startup

To configure the Bitcoin client so that mining on startup is automatic: Configure bitcoin.conf as follows:

gen=1

Linux