Validator Node

This document outlines the steps to deploy your own validator node.

Hardware Requirement

- Memory: 64 GB
- CPU: 8 cores
- Disk: 1 TB NVME SSD
- Bandwidth: 100 MBps for Download / Upload

Server Timezone Configuration

Make sure your server timezone configuration is UTC. Check your current timezone by running timedatectl

Note: Having a different timezone configuration may cause a LastResultHash mismatch error and take down your node!

Install 0gchaind via CLI

git clone -b v0.2.3 https://github.com/0glabs/0g-chain.git
./0g-chain/networks/testnet/install.sh
source ~/.profile

Set Chain ID

0gchaind config chain-id zgtendermint_16600-2

Initialize Node

We need to initialize the node to create all the necessary validator and node configuration files:

0gchaind init <your_validator_name> --chain-id zgtendermint_16600-2

Note: the validator name can only contain ASCII characters.

By default, the init command creates config and data folder under ~/.0gchain(i.e $HOME). In the config directory, the most important files for configuration are app.toml and config.toml.

Note: you could specify --home to overwrite the default work directory.

Genesis & Seeds

Copy the Genesis File

Check the genesis.json file and copy it over to the config directory $HOME/.0gchain/config/genesis.json. This is a genesis file with the chain-id and genesis accounts balances.

sudo apt install -y unzip wget
rm ~/.0gchain/config/genesis.json
wget -P ~/.0gchain/config https://github.com/0glabs/0g-chain/releases/download/v0.2.3/genesis.json

Then verify the correctness of the genesis configuration file:

0gchaind validate-genesis

Add Seed Nodes

Your node needs to know how to find peers. You’ll need to add healthy seed nodes to $HOME/.0gchain/config/config.toml.

The format of the config.toml file is as follows:

#######################################################
###           P2P Configuration Options             ###
#######################################################
[p2p]

# ...

# Comma separated list of seed nodes to connect to
seeds = "<node-id>@<ip>:<p2p port>"

We provide four seed nodes below.

81987895a11f6689ada254c6b57932ab7ed909b6@54.241.167.190:26656,010fb4de28667725a4fef26cdc7f9452cc34b16d@54.176.175.48:26656,e9b4bc203197b62cc7e6a80a64742e752f4210d5@54.193.250.204:26656,68b9145889e7576b652ca68d985826abd46ad660@18.166.164.232:26656

Add Persistent Peers

You can set the persistent_peers field in $HOME/.0gchain/config/config.toml to specify peers that your node will maintain persistent connections with.

Start Testnet

Start the node and sync up to the latest block height. Note that the first time you start the sync up, it may take longer time to run.

0gchaind start

Garbage Collection Optimization

To maximize sync speed for validators and other network providers that are running pruning nodes, the following settings are recommended:

• Start 0gchaind process with environment variable and value GOGC=900; this instructs the golang garbage collector to wait until the heap has grown to 9x it's initial allocated size before running garbage collection

• Start 0gchaind process with environment variable GOMEMLIMIT set to 66% of the total memory available to the 0gchaind process (e.g. GOMEMLIMIT=40GB for a node with 64 GB of memory) to ensure garbage collection runs whenever 66% of the total memory is used

Make sure you've synced your node to the latest block height before running the following steps.

Create Validator

You could either create a new account or import from an existing key. To create a new account:

0gchaind keys add <key_name> --eth

Here if you want to get the public address which starts with 0x, you could first run the following command to get your key’s private key.

0gchaind keys unsafe-export-eth-key <key_name>

Then import the returned private key to a wallet (Metamask for example) to get the public address.

As a next step, you must acquire some testnet tokens either by wallet transfer or requesting on the faucet before submitting your validator account address.

0gchaind tx staking create-validator \
  --amount=<staking_amount>ua0gi \
  --pubkey=$(0gchaind tendermint show-validator) \
  --moniker="<your_validator_name>" \
  --chain-id=zgtendermint_16600-2 \
  --commission-rate="0.10" \
  --commission-max-rate="0.20" \
  --commission-max-change-rate="0.01" \
  --min-self-delegation="1" \
  --from=<key_name> \
  --gas=auto \
  --gas-adjustment=1.4

Check that it is in the validator set:

0gchaind q staking validators -o json --limit=1000 | jq '.validators[] | select(.status=="BOND_STATUS_BONDED")' | jq -r '.tokens + " - " + .description.moniker' | sort -gr | nl

Only top 125 staked validators will be selected as active validators.

By any chance your validator is put in jail, use this command to unjail it

0gchaind tx slashing unjail --from <key_name> --gas=500000 --gas-prices=99999neuron -y

Upgrade Your Node

These instructions are for full nodes that have ran on previous versions of and would like to upgrade to the latest testnet version.

Reset Data

Note: if the version you are upgrading to is not breaking from the previous one, you should not reset the data. If this is the case you can skip to Restart step.

First, remove the outdated files and reset the data.

rm $HOME/.0gchain/config/addrbook.json $HOME/.0gchain/config/genesis.json
0gchaind tendermint unsafe-reset-all --home $HOME/.0gchain

Your node is now in a pristine state while keeping the original priv_validator.json and config.toml. If you had any sentry nodes or full nodes setup before, your node will still try to connect to them, but may fail if they haven’t also been upgraded.

Restart

0gchaind start

Migrate Your Node

Important files

If you are migrating your node to a different server, first you need to recover your wallet account on your new server。 If you have stored your wallet mnemonic, you can restore your account by executing

0gchaind keys add <your_account_name> --eth --recover

and paste your mnemonic to recover the account.

However, if by any chance you did not store your mnemonic, you need to make sure to store and move the following files to the new server at the same place under your $HOME.

• $HOME/xx.address

• $HOME/xx.info

• $HOME/keyhash

Another important file to store is $HOME/config/priv_validator_key.json. This file is generated at the init step and is the key file for your onchian signing.

Step

Follow the same setup process above to start syncing your node to the latest block height

Important: Delete $HOME/config/addrbook.json if you are using the same machine

Important: Make sure the genesis.json is updated

Important: Make sure the seeds are updated

Warning: Do not migrate the files before you finish syncing the blocks. This is to avoid double signing.

Warning: Do not stop your old server before you finish syncing the blocks. This is to avoid getting jailed for long downtime.

Once you finished syncing the blocks.

1. Stop your new server.

2. Copy and past the files mentioned in Important files to the $HOME on your new server.

3. Stop your old server.

4. Restart your new server.