Multi-Node Testnet

This document shows how to start a testnet of smartBCH with multiple nodes.

We suggest to use ubuntu 20.04.

Among these nodes, just pick one to generate the genesis file. And all the other nodes do not generate the genesis file, instead, they use the generated genesis file as is.

1. On the nodes which do not generate the genesis file

Step 0: build smartbchd

Please follow this document to build smartbchd , the executable of smartBCH's full node client.

Step 1: generate the private keys to operate one validator

cd ~/smart_bch/smartbch
./smartbchd gen-test-keys -n 1 --show-address | tee gen-test-keys.txt
2915b09298d0362df490fe3969b10aece94cd3460fb1ba29184cba31516a9b5f 0xF0c6969C2a554ddae639ba1Aa1d2fA11382CAb2B

The above command generates one private key. And the corresponding EOA address is 0xF0c6969C2a554ddae639ba1Aa1d2fA11382CAb2B.

Step 2: generate genesis validator consensus key info

Now we generate the ed25519 private key for consensus engine:

./smartbchd generate-consensus-key-info |tee generate-consensus-key-info.txt
a07871d10858179c1bb3c1f0d7bab31103135b76f96b6bd1f06a5bc0d350f862

The output hex string is consensus pubkey which will be used in generate-genesis-validator command, and a file containing the consensus public and private key is generated under the current directory, named priv_validator_key.json.

Step 3: generate genesis validator info using pubkey generated above

./smartbchd generate-genesis-validator \
	--validator-address=0xF0c6969C2a554ddae639ba1Aa1d2fA11382CAb2B \
	--consensus-pubkey=a07871d10858179c1bb3c1f0d7bab31103135b76f96b6bd1f06a5bc0d350f862 \
	--voting-power=1 \
	--staking-coin=0 \
	--introduction="happyman"
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

The validator-address is the one we get at step 1, and the consensus-pubkey is the one we get at step 2.

The output hex string contains the information of a validator. Send the this hex string to the node who is genesis-generator.

Step 4: wait for the data directory's tarball and unpack it

The genesis-generator will send you a tarball named dot.smartbchd.tgz, which contains the initial content for the data directory.

cd ~
tar zxvf dot.smartbchd.tgz
rm -rf .smartbchd
./smartbchd init mynode --chain-id 0x2711
cp -rf dot.smartbchd/* .smartbchd/

Step 5: Copy private key file to data directory and start node

Copy priv_validator_key.json generated in Step 2, to get the data directory:

cp ./priv_validator_key.json ~/.smartbchd/config/

Now start the node:

ulimit -n 65536
./smartbchd start

For the smartbchd start command, you can use --mainnet-url option to specify a bitcoincashnode's RPC endpoint, and use --home option to specifiy another data directory other than ~/.smartbchd .

Step 6: activate validator

Before you activate your genesis validator, try to get testnet BCH in your validator address, it needs at least

1000000000000000000000 bch

You can ask the genesis-generator to send you some testnet BCH. And you can check your balance with below command (Replace your_validator_address with your genesis validator address):

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getBalance","params":["your_validator_address","latest"],"id":1}' -H "Content-Type: application/json" http://localhost:8545

After you have enough bch, you can run the following command:

./smartbchd staking \
--validator-key=07427a59913df1ae8af709f60f536ddba122b0afa8908291471ca58c603a7447 \
--staking-coin=2000000000000000000000000 \
--nonce=0 \
--chain-id=0x2711

Note: replace the content after --validator-key with your validator private key, and repace the content after --staking-coin with 1000000000000000000000 or even more you have.

⚠️Keep your private key safe, and execute this command on a secure, offline machine

Then broadcast the transaction (replace --your_tx_data with what hex string get above):

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["you_tx_data"],"id":1}' -H "Content-Type: application/json" http://localhost:8545

Now, you had send an editValidator transaction to staking contract. Check this transaction's receipt (replace your_tx_hash with what the hex string you get above):

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getTransactionReceipt","params":["your_tx_hash"],"id":1}' -H "Content-Type: application/json" http://localhost:8545

If the status is 0x1, congratulations, your genesis validator is activated now.

2. On the node which generates the genesis file

Step 0: Prepare

Just finish the steps 0-5 as running a single-node testnet.

Step 1: add genesis validator info to genesis.json using hex strings sent by other nodes

Using ./smartbchd add-genesis-validator multiple times, one time with one hex string sent by one node. Finally you'll include all the validators' information in the genesis.json file.

Then, make a copy of the ~/.smartbchd directory, excluding the node_key.json file.

cp -r ~/.smartbchd ~/dot.smartbchd
rm ~/dot.smartbchd/config/node_key.json

Step 2: start the node

Run the step 6 and 7 as running a single-node testnet.

Step 4: collect seeds information

Collect the p2p seeds information and modify the ~/dot.smartbchd/config/config.toml file.

Step 5: send information to all the other nodes

Make a tarball:

cd ~
tar czvf dot.smartbchd.tgz dot.smartbchd

Then send this dot.smartbchd.tgz file to all the other nodes.

3. Join in as a validator after genesis

You can also join in an already-running smartBCH chain as a new validator.

Step 0: create new validator

Follow the step 0,1,2 described in the above section 1, to get the validator account key and the consensus key. Then, you can use these key information to build command below:

./smartbchd staking \
--validator-key=fceb6fbf700ae1faaf482fbaf7c3dfd2c8635956ed23a3eb1178e5d71ac34dbc \
--staking-coin=1000000000000000000000000 \
--consensus-pubkey=d4849694a7105200464dfc1160c95ed26664b556c3e468b03312ed9ebd937eb4 \
--type=create \
--nonce=0 \
--chain-id=0x2711

This command will output a hex string to be used in the next step.

Step 1: send transaction to register as a validator

Make sure you have enough BCH in you validator account.

Then broadcast the transaction (replace your_tx_data with what hex string get above):

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["you_tx_data"],"id":1}' -H "Content-Type: application/json" http://localhost:8545

OK, now you had send a createValidator transaction to the staking contract. Check this transaction's receipt (replace your_tx_hash with what the hex string you get in above command):

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getTransactionReceipt","params":["your_tx_hash"],"id":1}' -H "Content-Type: application/json" http://localhost:8545

If the status is 0x1, congratulations, your validator is created now, but it has no voting power now.

Step 2: voting in the BCH mainnet

Someone must vote for your validator to make it active in a future epoch. If you are using a fake BCH node, the voting for new validator can be started using the following command:

./bchnode/scripts pubkey.sh "you_consenesus_pubkey"-"you_voting_power"-add

Like this: ./pubkey.sh d4849694a7105200464dfc1160c95ed26664b556c3e468b03312ed9ebd937eb4-1-add

If you are using a real BCH node, please use getblocktemplate to specify the coinbase transaction for voting.

You can also starting voting before registering the validator, which can make sure then it is registered, it gets voting power as soon as possible.

4. Adjust minGasPrice

You can adjust minmum gas price that tx must pay for its gas in smartBCH chain, but only an active validator and its rewardTo address has permission to do this.

Step 0: generate minGasPrice adjust signed rawTx

Follow the step 0,1,2 described in the above section 1, to get the validator account key and the consensus key. Then, you can use these key information to build increase minGasPrice command below:

./smartbchd staking \
--validator-key=fceb6fbf700ae1faaf482fbaf7c3dfd2c8635956ed23a3eb1178e5d71ac34dbc \
--type=increase \
--nonce=0 \
--chain-id=0x2711

or decrease minGasPrice command below:

./smartbchd staking \
--validator-key=fceb6fbf700ae1faaf482fbaf7c3dfd2c8635956ed23a3eb1178e5d71ac34dbc \
--type=decrease \
--nonce=0 \
--chain-id=0x2711

These two command will output a hex string to be used in the next step.

Step 1: send transaction to adjust minGasPrice

Make sure you have enough BCH in you sender account.

Then broadcast the transaction (replace your_tx_data with what hex string get above):

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_sendRawTransaction","params":["you_tx_data"],"id":1}' -H "Content-Type: application/json" http://localhost:8545

OK, now you had send a increaseMinGasPrice transaction to the staking contract. Check this transaction's receipt (replace your_tx_hash with what the hex string you get in above command):

curl -X POST --data '{"jsonrpc":"2.0","method":"eth_getTransactionReceipt","params":["your_tx_hash"],"id":1}' -H "Content-Type: application/json" http://localhost:8545

If the status is 0x1, congratulations, your update success.