Skip to main content

Multi Node

Following this page, you can run a localnet setup with docker that consists of a 4-node local chain. This setup can be useful for developers to test their applications and protocol features on a multi-node setup.

A similar setup is used by the Guru team to get insights about the impact of new features and testing different user flows.

Build & Start​

To build start a 4 node testnet using docker, run:

make localnet-start

This command creates a 4-node network using the gurudnode Docker image. The ports for each node are found in this table:

Node IDP2P PortCometBFT RPC PortREST/ Ethereum JSON-RPC PortWebSocket Port
gurunode0266562665785458546
gurunode1266592666085478548
gurunode2266612666285498550
gurunode3266632666485518552

To update the binary, just rebuild it and restart the nodes

make localnet-start

The command above command will run containers in the background using Docker compose. You will see the network being created:

...
Creating network "guru_localnet" with driver "bridge"
Creating gurudnode0 ... done
Creating gurudnode2 ... done
Creating gurudnode1 ... done
Creating gurudnode3 ... done

Stop Localnet​

Once you are done, execute:

make localnet-stop

Configuration​

The make localnet-start creates files for a 4-node testnet in ./build by calling the gurud testnet command. This outputs a handful of files in the ./build directory:

tree -L 3 build/

build/
├── gurud
├── gurud
├── gentxs
│   ├── node0.json
│   ├── node1.json
│   ├── node2.json
│   └── node3.json
├── node0
│   ├── gurud
│   │   ├── key_seed.json
│   │   └── keyring-test-cosmos
│   └── gurud
│       ├── config
│       ├── data
│       └── gurud.log
├── node1
│   ├── gurud
│   │   ├── key_seed.json
│   │   └── keyring-test-cosmos
│   └── gurud
│       ├── config
│       ├── data
│       └── gurud.log
├── node2
│   ├── gurud
│   │   ├── key_seed.json
│   │   └── keyring-test-cosmos
│   └── gurud
│       ├── config
│       ├── data
│       └── gurud.log
└── node3
├── gurud
│   ├── key_seed.json
│   └── keyring-test-cosmos
└── gurud
    ├── config
    ├── data
    └── gurud.log

Each ./build/nodeN directory is mounted to the /gurud directory in each container.

Logging​

In order to see the logs of a particular node you can use the following command:

# node 0: daemon logs
docker exec gurudnode0 tail gurud.log

# node 0: REST & RPC logs
docker exec gurudnode0 tail gurud.log

The logs for the daemon will look like:

I[2020-07-29|17:33:52.452] starting ABCI with CometBFT                  module=main
E[2020-07-29|17:33:53.394] Can't add peer's address to addrbook         module=p2p err="Cannot add non-routable address 272a247b837653cf068d39efd4c407ffbd9a0e6f@192.168.10.5:26656"
E[2020-07-29|17:33:53.394] Can't add peer's address to addrbook         module=p2p err="Cannot add non-routable address 3e05d3637b7ebf4fc0948bbef01b54d670aa810a@192.168.10.4:26656"
E[2020-07-29|17:33:53.394] Can't add peer's address to addrbook         module=p2p err="Cannot add non-routable address 689f8606ede0b26ad5b79ae244c14cc67ab4efe7@192.168.10.3:26656"
I[2020-07-29|17:33:58.828] Executed block                               module=state height=88 validTxs=0 invalidTxs=0
I[2020-07-29|17:33:58.830] Committed state                              module=state height=88 txs=0 appHash=90CC5FA53CF8B5EC49653A14DA20888AD81C92FCF646F04D501453FD89FCC791
I[2020-07-29|17:34:04.032] Executed block                               module=state height=89 validTxs=0 invalidTxs=0
I[2020-07-29|17:34:04.034] Committed state                              module=state height=89 txs=0 appHash=0B54C4DB1A0DACB1EEDCD662B221C048C826D309FD2A2F31FF26BAE8D2D7D8D7
I[2020-07-29|17:34:09.381] Executed block                               module=state height=90 validTxs=0 invalidTxs=0
I[2020-07-29|17:34:09.383] Committed state                              module=state height=90 txs=0 appHash=75FD1EE834F0669D5E717C812F36B21D5F20B3CCBB45E8B8D415CB9C4513DE51
I[2020-07-29|17:34:14.700] Executed block                               module=state height=91 validTxs=0 invalidTxs=0
tip

You can disregard the Can't add peer's address to addrbook warning. As long as the blocks are being produced and the app hashes are the same for each node, there should not be any issues.

Whereas the logs for the REST & RPC server would look like:

I[2020-07-30|09:39:17.488] Starting application REST service (chain-id: "7305661614933169792")... module=rest-server
I[2020-07-30|09:39:17.488] Starting RPC HTTP server on 127.0.0.1:8545   module=rest-server
...

Follow Logs​

You can also watch logs as they are produced via Docker with the --follow (-f) flag, for example:

docker logs -f gurudnode0

Interact with the Localnet​

Ethereum JSON-RPC & Websocket Ports​

To interact with the testnet via WebSockets or RPC/API, you will send your request to the corresponding ports:

EVM JSON-RPCEth Websocket
85458546

You can send a curl command such as:

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_accounts","params":[],"id":1}' -H "Content-Type: application/json" 192.162.10.1:8545
tip

The IP address will be the public IP of the docker container.

Additional instructions on how to interact with the WebSocket can be found on the events documentation.

Keys & Accounts​

To interact with gurud and start querying state or creating txs, you use the gurud directory of any given node as your home, for example:

gurud keys list --home ./build/node0/gurud

Now that accounts exists, you may create new accounts and send those accounts funds!

tip

Note: Each node's seed is located at ./build/nodeN/gurud/key_seed.json and can be restored to the CLI using the gurud keys add --restore command

Special Binaries​

If you have multiple binaries with different names, you can specify which one to run with the BINARY environment variable. The path of the binary is relative to the attached volume. For example:

# Run with custom binary
BINARY=guru make localnet-start