How to join Binance Smart Chain as Validator?

What is Binance Smart Chain?

Binance Smart Chain is an innovative solution to bring programmability and interoperability to Binance Chain. Binance Smart Chain relies on a system of 21 validators with Proof of Staked Authority (PoSA) consensus that can support short block time and lower fees. The most bonded validator candidates of staking will become validators and produce blocks. The double-sign detection and other slashing logic guarantee security, stability, and chain finality.

What is Validator?

Binance Smart Chain relies on a set of validators who are responsible for committing new blocks in the blockchain. These validators participate in the consensus protocol by signing blocks that contain cryptographic signatures signed by each validator's private key. The validator set is determined by a staking module built on Binance Chain for Binance Smart Chain, and propagated every day UTC 00:00 from BC to BSC via Cross-Chain communication.

Economics

Validator's rewards come from transaction fees and commission fees from delegators.

Let us also assume that the reward for a block is 100 BNB and that a certain validator has 20% of self-bonded BNB and sets its commission rate to 20%. These tokens do not go directly to the proposer. Instead, they are shared among validators and delegators. These 100 BNB will be distributed according to each participant's stake:

Commission: 80*20%= 16 BNB Validator gets: 100*20% + Commission = 36 BNB All delegators get: 100*80% - Commission = 64 BNB

If validators double sign, are frequently offline, their staked BNB ( not including BNB of users that delegated to them) can be slashed. The penalty depends on the severity of the violation.

You can learn to see the revenue history from BitQuery's chart or a table of BscScan

Slashing conditions

  • Double-Sign Slash: 10000BNB
    • Details: Anyone can submit a slashing request on BC with the evidence of Double Sign of BSC, which should contain the 2 block headers with the same height and parent block, sealed by the offending validator.
  • Offline Slash: 50BNB
    • Details: If a validator missed more than 50 blocks every 24h, the blocking reward for validator will not be relayed to BC for distribution but shared with other better validators. If it missed more than 150 blocks every 24h, then this will be propagated back to BC where another Slashing will happen
  • Rewards for submitting double-sign evidence: 1000BNB
  • Double-Sign Jail time: 2^63-1 seconds
  • Downtime Jail time: 2 days
  • Too Low self-delegation Jail time: 1 day

Hardware

We strongly recommend not using a laptop if you are running a full node

It's recommended to run BSC software in VPS Servers (both with firewall):

If you are running a node in Testnet, 4CPU/8GB of RAM is sufficient

Steps to Be a Validator Candidate

1. Configure your VPS network ports, ssl, firewall

Note

If you are running a node in Testnet, 2CPU/8GB of RAM is sufficient.

We recommend using popular cloud providers as their reliability and uptime are close to 100%. These servers would be a good starting point: * DigitalOcean: CPU optimized droplet 32GB/16CPU * Amazon EC2: C5 instance * Google Cloud Engine: n1-highcpu-16

2. Install BSC Fullnode

Option 1: Build from source code

Make sure that you have installed Go 1.13+ and have added GOPATH to PATH environment variable

git clone https://github.com/binance-chain/bsc
# Enter the folder bsc was cloned into
cd bsc
# Comile and install bsc
make geth

Option 2: Download the binaries

or you can download the pre-build binaries from release page or follow the instructions below:

# Linux
wget --no-check-certificate https://github.com/binance-chain/bsc/releases/download/v1.0.6/geth_linux
# MacOS
wget --no-check-certificate https://github.com/binance-chain/bsc/releases/download/v1.0.6/geth_mac

Download the config files

Download genesis.json and config.toml by:

## mainet
wget --no-check-certificate  $(curl -s https://api.github.com/repos/binance-chain/bsc/releases/latest |grep browser_ |grep mainnet |cut -d\" -f4)
unzip mainnet.zip

## testnet
wget --no-check-certificate  $(curl -s https://api.github.com/repos/binance-chain/bsc/releases/latest |grep browser_ |grep testnet |cut -d\" -f4)
unzip testnet.zip

3.Write genesis state locally

geth --datadir node init genesis.json

You could see the following output:

INFO [05-19|14:53:17.468] Allocated cache and file handles         database=/Users/huangsuyu/Downloads/bsc/node/geth/chaindata cache=16.00MiB handles=16
INFO [05-19|14:53:17.498] Writing custom genesis block
INFO [05-19|14:53:17.501] Persisted trie from memory database      nodes=21 size=56.84KiB time=357.915µs gcnodes=0 gcsize=0.00B gctime=0s livenodes=1 livesize=-574.00B
INFO [05-19|14:53:17.502] Successfully wrote genesis state         database=chaindata hash=7d79cc…fb0d1e
INFO [05-19|14:53:17.503] Allocated cache and file handles         database=/Users/huangsuyu/Downloads/bsc/node/geth/lightchaindata cache=16.00MiB handles=16
INFO [05-19|14:53:17.524] Writing custom genesis block
INFO [05-19|14:53:17.525] Persisted trie from memory database      nodes=21 size=56.84KiB time=638.396µs gcnodes=0 gcsize=0.00B gctime=0s livenodes=1 livesize=-574.00B
INFO [05-19|14:53:17.528] Successfully wrote genesis state         database=lightchaindata hash=7d79cc…fb0d1e

4. Start a validator node

  • Sync Mode

    • Archive Sync

Archive mode means that all states of values in smart contracts as well as all balances of an account are stored.

You need to create an account that represents a key pair first. Use the following command to create a new account and set a password for that account: 

geth account new --datadir ./node

This command will return the public address and the path to your private key. BACKUP of keyfile is necessory!

If you already have an account, use the seed phrase to recover it:

geth account import --datadir ./node

Warning

Please do not expose your RPC endpoints to public network.

## generate the consensus key and input the password
geth account new --datadir ./node
echo {your-password} > password.txt
geth --config ./config.toml --datadir ./node -unlock {your-validator-address} --password password.txt  --mine --gcmode archive --allow-insecure-unlock  --pprofaddr 0.0.0.0 --metrics --pprof

Note

Because the default value of TrieTimeout in config.toml is large, it means geth will not persist state into database until reach this time threshold, if the node has been force shutdown, it will start syncing from last state which may take long time. The recommended setting for valiidators is TrieTimeout = 100000000000

Wait for node to sync

Your node should now be catching up with the network by replaying all the transactions from genesis and recreating the blockchain state locally. This will take a long time, so make sure you've set it up on a stable connection so you can leave while it syncs.

View the status of the network with https://bscscan.com/.

Congratulations! You've now successfully joined a network as a full node operator.

If you are connecting to an existing network for which you have a data backup (from a provider you trust), you can optionally load the backup into your node storage rather than syncing from scratch. Learn more here

5. Declare Candidacy

You can use bnbcli ortbnbcli binaryto declare your candidacy by self-stake some of BNB

Staking On Binance Chain

Use bnbcli to create an account or recover an account, make sure the account get more than 100 BNB. You can get BNB from https://testnet.binance.org/faucet-smart, but the BNB is on Binance Smart Chain, you can follow the guide to transfer BNB from BSC to BC.

Before sending create-validator transaction, make sure your bsc validator have already catched up. Command for create validator:

Example on mainnet

bnbcli staking bsc-create-validator \
-side-cons-addr {validator address} \
--side-fee-addr {wallet address on BSC} \
--address-delegator {wallet address on BC} \
--side-chain-id bsc \
--amount 10000000000:BNB \
--commission-rate {10000000 represent 10%} \
--commission-max-rate {20000000 represent 20%} \
--commission-max-change-rate {500000000 represent 5%} \
--moniker {validator name} \
--details {validator detailed description} \
--identity {keybase identity} \
--website {website for validator} \
--from {key name} \
--chain-id Binance-Chain-Tigris \
--node https://dataseed5.defibit.io:443
Example on testnet

tbnbcli staking bsc-create-validator \
--side-cons-addr {validator address} \
--side-fee-addr {wallet address on BSC} \
--address-delegator {wallet address on BC} \
--side-chain-id chapel \
--amount 10000000000:BNB \
--commission-rate {10000000 represent 10%} \
--commission-max-rate {20000000 represent 20%} \
--commission-max-change-rate {10000000 represent 1%} \
--moniker {validator name} \
--details {validator detailed description} \
--identity {keybase identity} \
--website {website for validator} \
--from {key name} \
--chain-id Binance-Chain-Ganges \
--node=http://data-seed-pre-1-s3.binance.org:80

Especially now that the side-cons-addr is the address you unlock when start the bsc node.

Read the detailed manual here

Go to explorer to verify your transactions.

5.Monitor node status

To get started quickly, run GethExporter in a Docker container.

docker run -it -d -p 9090:9090 \
  -e "GETH=http://mygethserverhere.com:8545" \
  hunterlong/gethexporter

Reference: https://grafana.com/grafana/dashboards/6976