Setup Celestia Light Client (Mocha Testnet) on a Ubuntu Linux 20.04 (LTS) x64 device.

Light Client: conducts data availability sampling on the Data Availability network.

A setup script, for easy install is available here:

Hardware Requirements : CPU: Single Core/ 2GB RAM/ Disk: 5 GB SSD/ 56Kbps Download/upload

This is incredibly lightweight requirements that you can even run on a Mobile phone, if you want to try this see

Install Pre-requisite Software

Update the system

sudo apt update && sudo apt upgrade -y

Install packages required for a Light node

sudo apt install curl tar wget clang pkg-config libssl-dev jq build-essential git make ncdu -y

Log in as root user

A lot of steps will require and only work under root user

sudo -i

you can exit root with exit

Install Go

Go is a programming language in which Celestia celestia-app and celestia-node are written in.

cd /tmp && wget https://go.dev/dl/go1.19.1.linux-amd64.tar.gz 
tar -C /usr/local/ -xzf go1.19.1.linux-amd64.tar.gz

Add to PATH

cd /usr/local/ && echo "export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin" >> ~/.bashrc && echo "export GOROOT=/usr/local/go" >> ~/.bashrc && echo "export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin" >> /home//.bashrc && echo "export GOROOT=/usr/local/go" >> /home//.bashrc && source ~/.bashrc && source /home/*/.bashrc

confirm installation with

go version

Install Celestia-node

Celestia Node is the software stack for Data availability nodes, Install the binary by running the following commands:

cd $HOME
rm -rf celestia-node
git clone https://github.com/celestiaorg/celestia-node.git
cd celestia-node/
git checkout tags/v0.6.0
make install
make cel-key

confirm installation with

celestia version

Initialize Light Node

celestia light init

Connect to gRPC endpoint

Start the light node with a connection to a validator node's gRPC endpoint (which is usually exposed on port 9090): This can be any validator node including your own.

Example Endpoint: https://rpc-mocha.pops.one:9090
Available Endpoints: https://docs.celestia.org/nodes/light-node/mocha-testnet#rpc-endpoints

Example to place in system service file

--core.ip https://rpc-mocha.pops.one:9090

Set up SystemD service for node

setup to run as a background process with SystemD. This enables the node to run continuously in the background unless stopped.

tee <<EOF >/dev/null /etc/systemd/system/celestia-lightd.service
[Unit]
Description=celestia-lightd Light Node
After=network-online.target

[Service]
User=$USER
ExecStart=/usr/local/bin/celestia light start --core.ip <RPCENDPOINT>
Restart=on-failure
RestartSec=3
LimitNOFILE=4096

[Install]
WantedBy=multi-user.target
EOF

Enable and Start Service

systemctl enable celestia-lightd
systemctl daemon-reload
systemctl start celestia-lightd

View Logs

journalctl -u celestia-lightd.service -f

Check service status

systemctl status celestia-lightd

Wallet

Once you start the Light Node, a wallet key will be generated for you. You will need to fund that address with testnet tokens to pay for PayForData transactions.

You can find the address by running the following command in the celestia-node directory:

cd celestia-node
./cel-key list --node.type light --keyring-backend test

The Address that’s displayed is what you fund in order to start pay for data transactions.