Key Whitelisting (option 1)

In key whitelisting mode, blockchain data is pulled by the seed from Zilliqa Research-hosted public seed nodes in periodic intervals. Exchanges using this mode generate a public-private key pair and share their public key with Zilliqa Research for whitelisting.

This section describes Option 1 for key whitelisting mode, which uses seed-configuration.tar.gz and requires opening an inbound port.

Preparing the Machine

Before you start, please ensure the steps below are done.

1. Choose and note down a port you wish to reserve for your seed node to receive incoming blockchain data.

important

The port of choice must be opened to inbound connections. Otherwise, the seed node will be unreachable.

Docker Setup

We highly recommend using Docker to set up a seed node, as we provide a tested, production-ready image for your use. If you have not yet set up docker, please follow the instructions on the official documentation.

Once you have set up Docker, you may proceed to download the configuration tarball for the Mainnet:

# create a directory

$ mkdir my_seed && cd my_seed

# download the seed node configuration files

$ curl -O https://mainnet-join.zilliqa.com/seed-configuration.tar.gz

$ tar -zxvf seed-configuration.tar.gz

# Contents:

#

# launch.sh

# constants.xml

# launch_docker.sh

# dsnodes.xml

# config.xml

Once you have successfully uncompressed the tarball, you should generate a new keypair for whitelisting by Zilliqa Research:

$ sudo docker run --rm zilliqa/zilliqa:<version> -c genkeypair

# for example: sudo docker run --rm zilliqa/zilliqa:v7.2.0 -c genkeypair

# output will be <public key> <private key>

The first value from the ouput is the public key and second value is the private key. The private key is required to start the seed node.

info

Any number of seed nodes can use this key pair simultaneously. Hence, you only need to provide one key for whitelisting no matter how many seed nodes you will be operating.

Native Setup

note

This approach has been tested on Ubuntu 18.04 and involves compiling C++. We strongly recommend you consider using the Docker image provided above.

If you cannot or do not wish to use Docker, you may also build the Zilliqa binary from source and run it as such.

# clone Zilliqa source files

$ git clone https://github.com/Zilliqa/Zilliqa.git && cd Zilliqa && git checkout

tags/<tag_id>

# install system dependencies

$ sudo apt-get update && sudo apt-get install \

git \

libboost-system-dev \

libboost-filesystem-dev \

libboost-test-dev \

libssl-dev \

libleveldb-dev \

libjsoncpp-dev \

libsnappy-dev \

cmake \

libmicrohttpd-dev \

libjsonrpccpp-dev \

build-essential \

pkg-config \

libevent-dev \

libminiupnpc-dev \

libcurl4-openssl-dev \

libboost-program-options-dev \

libboost-python-dev \

python3-dev \

python3-setuptools \

python3-pip \

gawk

# Run the following to install latest version of cmake.

# We suggest to install cmake 3.19 or any version >=3.16:

wget https://github.com/Kitware/CMake/releases/download/v3.19.3/cmake-3.19.3-Linux-x86_64.sh

mkdir -p "${HOME}"/.local

bash ./cmake-3.19.3-Linux-x86_64.sh --skip-license --prefix="${HOME}"/.local/

export PATH=$HOME/.local/bin:$PATH

cmake --version

rm cmake-3.19.3-Linux-x86_64.sh

$ export LC_ALL=C

$ pip3 install requests clint futures

# build the binary. this may take a while.

$ ./build.sh

The build should exit with no errors. Once it is complete, download the configuration tarball, and generate a keypair:

# make a separate folder for keys and configuration

$ cd ../ && mkdir my_seed && cd my_seed

# download the seed node configuration files

$ curl -O https://mainnet-join.zilliqa.com/seed-configuration.tar.gz

$ tar -zxvf seed-configuration.tar.gz

# Contents:

#

# launch.sh

# constants.xml

# launch_docker.sh

# dsnodes.xml

# config.xml

# generate a key pair for key whitelisting

$ ../Zilliqa/build/bin/genkeypair

# output will be <public key> <private key>

Configuring the Node

The node requires some configuration before it can successfully join the network. Most configuration is contained in constants.xml, which should be in the directory we extracted seed-configuration.tar.gz to. Minimally, the following changes are required:

• Change the value of ENABLE_WEBSOCKET to true if your seed node will support websockets (refer to the Zilliqa Websocket Server documentation).

Joining the Network

Once the preliminary steps have been completed, joining the network is relatively straightforward.

# NOTE: run only ONE of the following.

# for Docker setup

$ ./launch_docker.sh

# for native setup

$ ./launch.sh

You will be asked a series of questions. When asked to enter your listening port, please enter the value you noted down earlier. When asked to enter the private key. This is crucial, as your node will not work with anything else.

Sample instructions to be followed for launch are provided below.

• launch_docker.sh

$ ./launch_docker.sh

Assign a name to your container (default: zilliqa): <container_name>

Enter your IP address ('NAT' or *.*.*.*): <static ip address of machine>

Enter your listening port (default: 33133): <33133 or other selected port>

Use IP whitelisting registration approach (default: Y): N

Enter the private key (32-byte hex string) to be used by this node and whitelisted by upper seeds: <private key generated for key whitelisting>

• launch.sh

$ ./launch.sh

Enter the full path of your zilliqa source code directory: <zilliqa code directory path>

Enter the full path for persistence storage (default: current working directory): <default or custom path>

Enter your IP address ('NAT' or *.*.*.*): <static ip address>

Enter your listening port (default: 33133): <33133 or other selected port>

Use IP whitelisting registration approach (default: Y): N

Enter the private key (32-byte hex string) to be used by this node and whitelisted by upper seeds: <private key generated for key whitelisting>

Testing Your Seed Node's JSON-RPC Port

To check whether your node's JSON-RPC server is publicly available, you can use the following curl command.

curl -d '{

"id": "1",

"jsonrpc": "2.0",

"method": "GetBlockchainInfo",

"params": [""]

}' -H "Content-Type: application/json" -X POST "<seed node address>"

If you received the latest blockchain information (similar to the one below) from the seed node, your JSON-RPC service is running well.

{"id":"1","jsonrpc":"2.0","result":{"CurrentDSEpoch":"4789","CurrentMiniEpoch":"478809","DSBlockRate":0.00013455546527607284,"NumDSBlocks":"4790","NumPeers":2400,"NumTransactions":"3091806","NumTxBlocks":"478809","NumTxnsDSEpoch":"185","NumTxnsTxEpoch":"0","ShardingStructure":{"NumPeers":[600,600,600]},"TransactionRate":0,"TxBlockRate":0.013450003515398927}}

Testing Your Seed Node's WebSocket Port

You can use an online WebSocket test utility to test whether your WebSocket is publicly accessible.

1. Visit https://www.websocket.org/echo.html
2. Under location, put your WebSocket URL link (e.g., wss://<yourdomain here or ip:port>)
3. Click on connect
4. If “CONNECTED” is shown in the log, your WebSocket port is publicly accessible

Next Steps

If you have successfully completed the above steps, you should have a functioning seed node that exposes an RPC API on localhost:4201. You may further check the logs at zilliqa-00001-log.txt.

The following articles in this series will demonstrate a simple set of functions that can be used as a starting point for exchange developers to implement their own custom business logic around the Zilliqa blockchain. You may find the full source code of the example app in the same repository.