tendermint/docs/introduction/quick-start.md

Tendermint

Overview

This is a quick start guide. If you have a vague idea about how Tendermint works and want to get started right away, continue.

Install

Quick Install

On a fresh Ubuntu 16.04 machine can be done with this script, like so:

curl -L https://git.io/fFfOR | bash
source ~/.profile

WARNING: do not run the above on your local machine.

The script is also used to facilitate cluster deployment below.

Manual Install

Requires:

• go minimum version 1.10
• $GOPATH environment variable must be set
• $GOPATH/bin must be on your $PATH (see here)

To install Tendermint, run:

go get github.com/tendermint/tendermint
cd $GOPATH/src/github.com/tendermint/tendermint
make get_tools && make get_vendor_deps
make install

Note that go get may return an error but it can be ignored.

Confirm installation:

$ tendermint version
0.23.0

Note: see the releases page and the latest version should match what you see above.

Initialization

Running:

tendermint init

will create the required files for a single, local node.

These files are found in $HOME/.tendermint:

$ ls $HOME/.tendermint

config.toml  data  genesis.json  priv_validator.json

For a single, local node, no further configuration is required. Configuring a cluster is covered further below.

Local Node

Start tendermint with a simple in-process application:

tendermint node --proxy_app=kvstore

and blocks will start to stream in:

I[01-06|01:45:15.592] Executed block                               module=state height=1 validTxs=0 invalidTxs=0
I[01-06|01:45:15.624] Committed state                              module=state height=1 txs=0 appHash=

Check the status with:

curl -s localhost:26657/status

Sending Transactions

With the kvstore app running, we can send transactions:

curl -s 'localhost:26657/broadcast_tx_commit?tx="abcd"'

and check that it worked with:

curl -s 'localhost:26657/abci_query?data="abcd"'

We can send transactions with a key and value too:

curl -s 'localhost:26657/broadcast_tx_commit?tx="name=satoshi"'

and query the key:

curl -s 'localhost:26657/abci_query?data="name"'

where the value is returned in hex.

Cluster of Nodes

First create four Ubuntu cloud machines. The following was tested on Digital Ocean Ubuntu 16.04 x64 (3GB/1CPU, 20GB SSD). We'll refer to their respective IP addresses below as IP1, IP2, IP3, IP4.

Then, ssh into each machine, and execute this script:

curl -L https://git.io/fFfOR | bash
source ~/.profile

This will install go and other dependencies, get the Tendermint source code, then compile the tendermint binary.

Next, use the tendermint testnet command to create four directories of config files (found in ./mytestnet) and copy each directory to the relevant machine in the cloud, so that each machine has $HOME/mytestnet/node[0-3] directory. Then from each machine, run:

tendermint node --home ./mytestnet/node0 --proxy_app=kvstore --p2p.persistent_peers="ID1@IP1:26656,ID2@IP2:26656,ID3@IP3:26656,ID4@IP4:26656"
tendermint node --home ./mytestnet/node1 --proxy_app=kvstore --p2p.persistent_peers="ID1@IP1:26656,ID2@IP2:26656,ID3@IP3:26656,ID4@IP4:26656"
tendermint node --home ./mytestnet/node2 --proxy_app=kvstore --p2p.persistent_peers="ID1@IP1:26656,ID2@IP2:26656,ID3@IP3:26656,ID4@IP4:26656"
tendermint node --home ./mytestnet/node3 --proxy_app=kvstore --p2p.persistent_peers="ID1@IP1:26656,ID2@IP2:26656,ID3@IP3:26656,ID4@IP4:26656"

Note that after the third node is started, blocks will start to stream in because >2/3 of validators (defined in the genesis.json) have come online. Seeds can also be specified in the config.toml. See here for more information about configuration options.

Transactions can then be sent as covered in the single, local node example above.