How to set up a Chainlink Node?

Blockchain has witnessed a staggering rise in popularity, with decentralization and security as its valuable traits. However, the ability of blockchain to maintain the integrity by limiting the input data from external sources faced some limitations. So, it exhibited the need to introduce a bridge to help blockchain networks acquire input from different sources without disrupting its decentralized nature.
It is how chainlink came into existence and acquired a lot of traction as a decentralized oracle technology. Hence, unlike other oracle designs that rely on centralized gateways, chainlink is developed on a network of independent node operators offering unique integrations to numerous blockchain applications.

According to Digital coin, it is anticipated that the chainlink will be trading at $31.64 in 2021. Moreover, the value of LINK is predicted to reach as high as $44.91 by the end of 2024. This article sheds light on the significance of chainlink fundamentals and the necessary steps to establish a chainlink node by answering the following questions:

• What is Chainlink Node?
• Why is Chainlink necessary?
• What are the technical requirements to operate the Chainlink Node?
• How to set up a Chainlink Node?

What is Chainlink Node?

Chainlink is a decentralized platform network that provides real-world datasets like events, data feeds and information to smart contracts via oracles from off-blockchain sources to on blockchain. It enables smart contracts to interact securely with real-world data and services existing outside the blockchain networks. Smart contracts are pre-specified agreements on the blockchain that evaluate information and execute when certain conditions are met. In chainlink, LINK tokens are used as digital assets to pay for services on the network.

Chainlink plays an important role in bridging the gap between traditional data and the future of blockchain technology. It enables smart contracts to interface with real-world information, providing them with secure access to key data resources. Thus, chainlink offers reliable, tamper-proof inputs and outputs on any blockchain network. The key areas of focus to enable chainlink network include:

• Improving smart contracts ecosystem to build better blockchain applications.
• Building the improved reference implementation of chainlink.
• Providing access to data, payments and other API services.

Why is chainlink necessary?

Chainlink aims to solve the smart contract connectivity problem. This problem refers to an inability of a smart contract to interact with any other resources running outside the node network. When smart contracts need to deal with off-chain data, this data must be in a similar format as on-chain data. The difficulty of connecting the outside data to blockchain in such a language that both on-chain and off-chain sources can understand limits the usability of smart contracts.

As a result, the oracle was introduced into the blockchain ecosystem to bring about off-chain data to on-chain. Oracle plays a crucial role in retrieving and providing external data to the blockchain and smart contracts through APIs. As centralized oracles reduced the blockchain benefits due to faulty and alterable nature, chainlink came into existence.

Chainlink offers a wide range of decentralized services to smart contracts such as:

• Price feed (financial market data of DeFi economy).
• Verifiable randomness (creating dynamic NFTs and on-chain gaming apps).
• Proof-of-reserve ( offers proof of off-chain collateral that is backing stablecoins and cross-chain tokens).
• Keeper network (autonomous DevOps Services).

Chainlink node exhibit a minimal set of hardware requirements to operate. It can run with 1core, 1 to 2 GB RAM for better reliability. Connectivity is highly essential to establish communication between the Ethereum client and the blockchain. If you prefer to run your own Ethereum client, you will need to run it on a separate machine. 

There are few technical requirements within the chainlink set up for smooth and reliable operation. A chainlink node operator needs the following core components to deliver external data to smart contracts. Each chainlink node operator interacts with the following mentioned components regularly. Altogether, they build up a chainlink node and allow the secure delivery of data to any blockchain.

• Chainlink Node client software 

  It is an open-source infrastructure that bridges the on-chain and off-chain environments.

• On-chain oracle contract 

  The smart contracts of the chainlink node track the data queries and generate responses back to the user’s smart contract requests.

• Data source subscriptions 

  Chainlink nodes must connect with the off-chain data source APIs to fetch data to request smart contracts.

• External monitoring systems

  Peripheral off-chain infrastructure is essential to monitor the performance and reliability of a Chainlink node in real-time.

How to set up a chainlink node?

Follow this 10 steps process to set up the Chainlink Node and its PostgreSQL database with Docker

Step 1: Create the directories for the Chainlink Database and the Chainlink Node:

mkdir -p chainlink/db
mkdir -p chainlink/chainlink_goreli

Step 2: Create the container for the PostgreSQL database

docker run --name postgres-chainlink -v $HOME/chainlink/db:/var/lib/postgresql/data -e POSTGRES_PASSWORD=myPostgresPW -d -p 5432:5432 postgres:11.12

Step 3: Create the chainlink Postgres user in postgres database container:

docker exec -it postgres-chainlink psql -U postgres -c "CREATE USER chainlink WITH PASSWORD 'myChainlinkPW';"

Step 4: Create the Chainlink Database (for the goreli test-network in this sample)

docker exec -it postgres-chainlink psql -U postgres -c "CREATE DATABASE "chainlink_goreli";"

Step 5: Grant the privileges to the chainlink user

docker exec -it postgres-chainlink psql -U postgres -c "GRANT ALL PRIVILEGES ON DATABASE "chainlink_goreli" TO chainlink;"

Step 6: Create the .env file for the chainlink node and refer to the required Ethereum network and to our new Postgres Database

Step 7: For Infura url: https://app.infura.io
Example connection setting. Replace YOUR_PROJECT_ID with the ID Infura provides you on your project settings page.
Goerli

ETH_URL=wss://goerli.infura.io/ws/v3/YOUR_PROJECT_ID

nano chainlink/chainlink_goreli/.env

and enter

ROOT=/chainlink
LOG_LEVEL=debug
ETH_CHAIN_ID=5
MIN_OUTGOING_CONFIRMATIONS=2
LINK_CONTRACT_ADDRESS=0x01FZ23485060835E02A66ef475b0Cc51aA1e0709
CHAINLINK_TLS_PORT=0
SECURE_COOKIES=false
GAS_UPDATER_ENABLED=true
ALLOW_ORIGINS=*
ETH_URL=wss://goreli.infura.io/ws/v3/<YOUR_INFURA_PROJECT_ID>
DATABASE_URL=postgresql://chainlink:myChainlinkPW@localhost:5432/chainlink_goreli?sslmode=disable

For this demo, we are using Infura as an external provider for the connectivity to the Ethereum blockchain. If you want to use Infura as well, make sure that you adapt the Infura Project ID accordingly. Also, make sure that you use the same Chainlink Postgres password here that you have used to create the Chainlink Postgres User before.

Step 8: Create the .password file, which holds the password for your node wallet

nano chainlink/chainlink_goreli/.password

Enter your password for your node wallet. This password must be

• longer than 12 characters
• containing at least 3 uppercase characters
• containing at least 3 numbers
• containing at least 3 symbols

Step 9: Create the .api file, which holds the credentials for the GUI interface of the node

nano chainlink/chainlink_goreli/.api

Next, enter your email address and password. This password must be 8 to 50 characters.

<YOUR_EMAIL_ADDRESS>
<YOUR_NODE_GUI_PASSWORD>

Step 10: Now we can create the container for the chainlink node itself

docker run --name chainlink_goreli --network host -p 6688:6688 -v $HOME/chainlink/chainlink_goreli:/chainlink -it --env-file=$HOME/chainlink/chainlink_goreli/.env smartcontract/chainlink:0.10.8 local n -p /chainlink/.password -a /chainlink/.api

Note that we have added “–network host” to the command since we run the database locally from the node’s perspective.

Access the GUI of your new Chainlink node:

Access the GUI of your new Chainlink Node http://localhost:6688
Maintenance – How to stop and start your chainlink containers from your VM SSH shell?

Stop and start the PostgresSQL Database container:

docker stop postgres-chainlink

docker start postgres-chainlink

Stop and start the Chainlink Node container:

docker stop chainlink_goreli

docker start chainlink_goreli

To start a Docker container with the name chainlink_goreli in interactive mode use the following command –

docker start -i chainlink_goreli

To detach from and attach to the Chainlink Node container:

Ctrl-PQ

docker attach chainlink_goreli

Conclusion

Chainlink serves as an important oracle network to bridge the blockchain to the real world in a decentralized manner. It works actively to facilitate smart contracts for quick implementation and secured interaction with an ample collection of external inputs and outputs in the form of on-chain contracts. Apart from enabling the interaction between the smart contracts and external systems, it allows the smart contracts to extend the use cases across a more diverse set of markets.

Chainlink technology holds immense potential for DeFi and other crypto ecosystems. With a high level of security, transparency and trust, delivering the data through an open network of nodes becomes feasible, thereby allowing anyone to run their node, participate in Chainlink staking, and provide data to smart contracts. Therefore, chainlink can be used for numerous applications which can benefit from the transparency, efficiency, and security of blockchain-based smart contracts.

If you are looking to set up a chainlink node or overcome blockchain oracle issues, reach out to our experts, who can actively assist you with our Chainlink blockchain development services. So, connect with our team to explore the full chainlink potential for your business requirements.