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Official Golang execution layer implementation of the Ethereum protocol.

Automated builds are available for stable releases and the unstable master branch. Binaryarchives are published athttps://geth.ethereum.org/downloads/.

For prerequisites and detailed build instructions please read theInstallation Instructions.

Buildinggeth requires both a Go (version 1.18 or later) and a C compiler. You can installthem using your favourite package manager. Once the dependencies are installed, run

make geth

or, to build the full suite of utilities:

make all

The go-ethereum project comes with several wrappers/executables found in thecmddirectory.

Going through all the possible command line flags is out of scope here (please consult ourCLI Wiki page),but we've enumerated a few common parameter combos to get you up to speed quicklyon how you can run your owngeth instance.

Minimum:

• CPU with 2+ cores
• 4GB RAM
• 1TB free storage space to sync the Mainnet
• 8 MBit/sec download Internet service

Recommended:

• Fast CPU with 4+ cores
• 16GB+ RAM
• High-performance SSD with at least 1TB of free space
• 25+ MBit/sec download Internet service

By far the most common scenario is people wanting to simply interact with the Ethereumnetwork: create accounts; transfer funds; deploy and interact with contracts. For thisparticular use case, the user doesn't care about years-old historical data, so we cansync quickly to the current state of the network. To do so:

$ geth console

This command will:

• Startgeth in snap sync mode (default, can be changed with the--syncmode flag),causing it to download more data in exchange for avoiding processing the entire historyof the Ethereum network, which is very CPU intensive.
• Start the built-in interactiveJavaScript console,(via the trailingconsole subcommand) through which you can interact usingweb3 methods(note: theweb3 version bundled withingeth is very old, and not up to date with official docs),as well asgeth's ownmanagement APIs.This tool is optional and if you leave it out you can always attach it to an already runninggeth instance withgeth attach.

Transitioning towards developers, if you'd like to play around with creating Ethereumcontracts, you almost certainly would like to do that without any real money involved untilyou get the hang of the entire system. In other words, instead of attaching to the mainnetwork, you want to join thetest network with your node, which is fully equivalent tothe main network, but with play-Ether only.

$ geth --goerli console

Theconsole subcommand has the same meaning as above and is equallyuseful on the testnet too.

Specifying the--goerli flag, however, will reconfigure yourgeth instance a bit:

• Instead of connecting to the main Ethereum network, the client will connect to the Görlitest network, which uses different P2P bootnodes, different network IDs and genesisstates.
• Instead of using the default data directory (~/.ethereum on Linux for example),gethwill nest itself one level deeper into agoerli subfolder (~/.ethereum/goerli onLinux). Note, on OSX and Linux this also means that attaching to a running testnet noderequires the use of a custom endpoint sincegeth attach will try to attach to aproduction node endpoint by default, e.g.,geth attach <datadir>/goerli/geth.ipc. Windows users are not affected bythis.

Note: Although some internal protective measures prevent transactions fromcrossing over between the main network and test network, you should alwaysuse separate accounts for play and real money. Unless you manually moveaccounts,geth will by default correctly separate the two networks and will not make anyaccounts available between them.

Go Ethereum also supports connecting to the older proof-of-authority based test networkcalledRinkeby which is operated by members of the community.

$ geth --rinkeby console

In addition to Görli and Rinkeby, Geth also supports the ancient Ropsten testnet. TheRopsten test network is based on the Ethash proof-of-work consensus algorithm. As such,it has certain extra overhead and is more susceptible to reorganization attacks due to thenetwork's low difficulty/security.

$ geth --ropsten console

Note: Older Geth configurations store the Ropsten database in thetestnet subdirectory.

As an alternative to passing the numerous flags to thegeth binary, you can also pass aconfiguration file via:

$ geth --config /path/to/your_config.toml

To get an idea of how the file should look like you can use thedumpconfig subcommand toexport your existing configuration:

$ geth --your-favourite-flags dumpconfig

Note: This works only withgeth v1.6.0 and above.

One of the quickest ways to get Ethereum up and running on your machine is by usingDocker:

docker run -d --name ethereum-node -v /Users/alice/ethereum:/root \           -p 8545:8545 -p 30303:30303 \           ethereum/client-go

This will startgeth in snap-sync mode with a DB memory allowance of 1GB, as theabove command does. It will also create a persistent volume in your home directory forsaving your blockchain as well as map the default ports. There is also analpine tagavailable for a slim version of the image.

Do not forget--http.addr 0.0.0.0, if you want to access RPC from other containersand/or hosts. By default,geth binds to the local interface and RPC endpoints are notaccessible from the outside.

As a developer, sooner rather than later you'll want to start interacting withgeth and theEthereum network via your own programs and not manually through the console. To aidthis,geth has built-in support for a JSON-RPC based APIs (standard APIsandgeth specific APIs).These can be exposed via HTTP, WebSockets and IPC (UNIX sockets on UNIX basedplatforms, and named pipes on Windows).

The IPC interface is enabled by default and exposes all the APIs supported bygeth,whereas the HTTP and WS interfaces need to manually be enabled and only expose asubset of APIs due to security reasons. These can be turned on/off and configured asyou'd expect.

HTTP based JSON-RPC API options:

• --http Enable the HTTP-RPC server
• --http.addr HTTP-RPC server listening interface (default:localhost)
• --http.port HTTP-RPC server listening port (default:8545)
• --http.api API's offered over the HTTP-RPC interface (default:eth,net,web3)
• --http.corsdomain Comma separated list of domains from which to accept cross origin requests (browser enforced)
• --ws Enable the WS-RPC server
• --ws.addr WS-RPC server listening interface (default:localhost)
• --ws.port WS-RPC server listening port (default:8546)
• --ws.api API's offered over the WS-RPC interface (default:eth,net,web3)
• --ws.origins Origins from which to accept WebSocket requests
• --ipcdisable Disable the IPC-RPC server
• --ipcapi API's offered over the IPC-RPC interface (default:admin,debug,eth,miner,net,personal,txpool,web3)
• --ipcpath Filename for IPC socket/pipe within the datadir (explicit paths escape it)

You'll need to use your own programming environments' capabilities (libraries, tools, etc) toconnect via HTTP, WS or IPC to ageth node configured with the above flags and you'llneed to speakJSON-RPC on all transports. Youcan reuse the same connection for multiple requests!

Note: Please understand the security implications of opening up an HTTP/WS basedtransport before doing so! Hackers on the internet are actively trying to subvertEthereum nodes with exposed APIs! Further, all browser tabs can access locallyrunning web servers, so malicious web pages could try to subvert locally availableAPIs!

Maintaining your own private network is more involved as a lot of configurations taken forgranted in the official networks need to be manually set up.

First, you'll need to create the genesis state of your networks, which all nodes need to beaware of and agree upon. This consists of a small JSON file (e.g. call itgenesis.json):

{"config": {"chainId":<arbitrary positive integer>,"homesteadBlock":0,"eip150Block":0,"eip155Block":0,"eip158Block":0,"byzantiumBlock":0,"constantinopleBlock":0,"petersburgBlock":0,"istanbulBlock":0,"berlinBlock":0,"londonBlock":0  },"alloc": {},"coinbase":"0x0000000000000000000000000000000000000000","difficulty":"0x20000","extraData":"","gasLimit":"0x2fefd8","nonce":"0x0000000000000042","mixhash":"0x0000000000000000000000000000000000000000000000000000000000000000","parentHash":"0x0000000000000000000000000000000000000000000000000000000000000000","timestamp":"0x00"}

The above fields should be fine for most purposes, although we'd recommend changingthenonce to some random value so you prevent unknown remote nodes from being ableto connect to you. If you'd like to pre-fund some accounts for easier testing, createthe accounts and populate thealloc field with their addresses.

"alloc": {"0x0000000000000000000000000000000000000001": {"balance":"111111111"  },"0x0000000000000000000000000000000000000002": {"balance":"222222222"  }}

With the genesis state defined in the above JSON file, you'll need to initializeeverygeth node with it prior to starting it up to ensure all blockchain parameters are correctlyset:

$ geth init path/to/genesis.json

With all nodes that you want to run initialized to the desired genesis state, you'll need tostart a bootstrap node that others can use to find each other in your network and/or overthe internet. The clean way is to configure and run a dedicated bootnode:

$ bootnode --genkey=boot.key$ bootnode --nodekey=boot.key

With the bootnode online, it will display anenode URLthat other nodes can use to connect to it and exchange peer information. Make sure toreplace the displayed IP address information (most probably[::]) with your externallyaccessible IP to get the actualenode URL.

Note: You could also use a full-fledgedgeth node as a bootnode, but it's the lessrecommended way.

With the bootnode operational and externally reachable (you can trytelnet <ip> <port> to ensure it's indeed reachable), start every subsequentgethnode pointed to the bootnode for peer discovery via the--bootnodes flag. It willprobably also be desirable to keep the data directory of your private network separated, sodo also specify a custom--datadir flag.

$ geth --datadir=path/to/custom/data/folder --bootnodes=<bootnode-enode-url-from-above>

Note: Since your network will be completely cut off from the main and test networks, you'llalso need to configure a miner to process transactions and create new blocks for you.

Mining on the public Ethereum network is a complex task as it's only feasible using GPUs,requiring an OpenCL or CUDA enabledethminer instance. For information on such asetup, please consult theEtherMining subredditand theethminer repository.

In a private network setting, however, a single CPU miner instance is more than enough forpractical purposes as it can produce a stable stream of blocks at the correct intervalswithout needing heavy resources (consider running on a single thread, no need for multipleones either). To start ageth instance for mining, run it with all your usual flags, extendedby:

$ geth<usual-flags> --mine --miner.threads=1 --miner.etherbase=0x0000000000000000000000000000000000000000

Which will start mining blocks and transactions on a single CPU thread, crediting allproceedings to the account specified by--miner.etherbase. You can further tune the miningby changing the default gas limit blocks converge to (--miner.targetgaslimit) and the pricetransactions are accepted at (--miner.gasprice).

Thank you for considering helping out with the source code! We welcome contributionsfrom anyone on the internet, and are grateful for even the smallest of fixes!

If you'd like to contribute to go-ethereum, please fork, fix, commit and send a pull requestfor the maintainers to review and merge into the main code base. If you wish to submitmore complex changes though, please check up with the core devs first onour Discord Serverto ensure those changes are in line with the general philosophy of the project and/or getsome early feedback which can make both your efforts much lighter as well as our reviewand merge procedures quick and simple.

Please make sure your contributions adhere to our coding guidelines:

• Code must adhere to the official Goformattingguidelines (i.e. usesgofmt).
• Code must be documented adhering to the official Gocommentaryguidelines.
• Pull requests need to be based on and opened against themaster branch.
• Commit messages should be prefixed with the package(s) they modify.
  • E.g. "eth, rpc: make trace configs optional"

Please see theDevelopers' Guidefor more details on configuring your environment, managing project dependencies, andtesting procedures.

The go-ethereum library (i.e. all code outside of thecmd directory) is licensed under theGNU Lesser General Public License v3.0,also included in our repository in theCOPYING.LESSER file.

The go-ethereum binaries (i.e. all code inside of thecmd directory) are licensed under theGNU General Public License v3.0, alsoincluded in our repository in theCOPYING file.