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Setting up a Celestia consensus full node

Consensus Full Nodes allow you to sync blockchain history in the Celestia Consensus Layer.

Consensus Full Node

Hardware requirements​

The following hardware minimum requirements are recommended for running the Consensus Full Node:

  • Memory: 8 GB RAM
  • CPU: Quad-Core
  • Disk: 250 GB SSD Storage
  • Bandwidth: 1 Gbps for Download/100 Mbps for Upload

Setting up a consensus full node​

The following tutorial is done on an Ubuntu Linux 20.04 (LTS) x64 instance machine.

Setup the dependencies​

Follow the instructions on installing the dependencies here.

Install celestia-app​

Follow the tutorial on installing celestia-app here.

Setup the P2P networks​

Now we will setup the P2P Networks by cloning the networks repository:

cd $HOME
rm -rf networks
git clone https://github.com/celestiaorg/networks.git

To initialize the network pick a "node-name" that describes your node. The --chain-id parameter we are using here is mocha. Keep in mind that this might change if a new testnet is deployed.

celestia-appd init "node-name" --chain-id mocha

Copy the genesis.json file. For mocha we are using:

cp $HOME/networks/mocha/genesis.json $HOME/.celestia-app/config

Set seeds and peers:

PERSISTENT_PEERS=$(curl -sL https://raw.githubusercontent.com/celestiaorg/networks/master/mocha/peers.txt | tr -d '\n')
echo $PERSISTENT_PEERS
sed -i.bak -e "s/^persistent_peers *=.*/persistent_peers = \"$PERSISTENT_PEERS\"/" $HOME/.celestia-app/config/config.toml

Note: You can find more peers here.

Configure pruning​

For lower disk space usage we recommend setting up pruning using the configurations below. You can change this to your own pruning configurations if you want:

PRUNING="custom"
PRUNING_KEEP_RECENT="100"
PRUNING_INTERVAL="10"

sed -i -e "s/^pruning *=.*/pruning = \"$PRUNING\"/" $HOME/.celestia-app/config/app.toml
sed -i -e "s/^pruning-keep-recent *=.*/pruning-keep-recent = \
\"$PRUNING_KEEP_RECENT\"/" $HOME/.celestia-app/config/app.toml
sed -i -e "s/^pruning-interval *=.*/pruning-interval = \
\"$PRUNING_INTERVAL\"/" $HOME/.celestia-app/config/app.toml

Reset network​

This will delete all data folders so we can start fresh:

celestia-appd tendermint unsafe-reset-all --home $HOME/.celestia-app

Syncing​

By default, a consensus node will sync using block sync; that is request, validate and execute every block up to the head of the blockchain. This is the most secure mechanism yet the slowest (taking up to days depending on the height of the blockchain).

There are two alternatives for quicker syncing.

State sync​

State sync uses light client verification to verify state snapshots from peers and then apply them. State sync relies on weak subjectivity; a trusted header (specifically the hash and height) must be provided. This can be found by querying a trusted RPC endpoint (/block). RPC endpoints are also required for retrieving light blocks. These can be found in the docs here under the respective networks or from the chain-registry.

In $HOME/.celestia-app/config/config.toml, set

rpc_servers = ""
trust_height = 0
trust_hash = ""

to their respective fields. At least two different rpc endpoints should be provided. The more, the greater the chance of detecting any fraudulent behavior.

Once setup, you should be ready to start the node as normal. In the logs, you should see: Discovering snapshots. This may take a few minutes before snapshots are found depending on the network topology.

Quick sync​

Quick sync effectively downloads the entire data directory from a third-party provider meaning the node has all the application and blockchain state as the node it was copied from.

Run the following command to quick-sync from a snapshot for mocha:

cd $HOME
rm -rf ~/.celestia-app/data
mkdir -p ~/.celestia-app/data
SNAP_NAME=$(curl -s https://snaps.qubelabs.io/celestia/ | \
    egrep -o ">mocha.*tar" | tr -d ">")
wget -O - https://snaps.qubelabs.io/celestia/${SNAP_NAME} | tar xf - \
    -C ~/.celestia-app/data/

Start the celestia-app​

In order to start your consensus full node, run the following:

celestia-appd start

Follow the tutorial on setting up Celestia-App as a background process with SystemD here.

Optional: configure for RPC endpoint​

You can configure your Consensus Full Node to be a public RPC endpoint and listen to any connections from Data Availability Nodes in order to serve requests for the Data Availability API here.

Run the following commands:

EXTERNAL_ADDRESS=$(wget -qO- eth0.me)
sed -i.bak -e "s/^external-address = \"\"/external-address = \"$EXTERNAL_ADDRESS:26656\"/" $HOME/.celestia-app/config/config.toml
sed -i 's#"tcp://127.0.0.1:26657"#"tcp://127.0.0.1:26657"#g' ~/.celestia-app/config/config.toml

Restart celestia-appd in the previous step to load those configs.

Transaction indexer configuration options​

This section will show you how to set your config.toml file in celestia-app to chose which transactions to index. In some cases, a node operator will be able to decide which transactions to index based on configuration set in the application.

The options are:

  1. null
  2. kv (default) - the simplest possible indexer backed by key-value storage (defaults to levelDB; see DBBackend)
    1. when kv is chosen tx.height and tx.hash will always be indexed
  3. psql - the indexer services backed by PostgreSQL
    1. when kv or psql is chosen, tx.height and tx.hash will always be indexed