Skip to main content

Registering a Stake Address

Registering a new stake pool involves two steps - Registering a stake address and registering the the pool metadata. The stake address needs to be registered on the blockchain to be useful and it requires:

  • Creating a registration certificate.
  • Submitting the certificate to the blockchain with a transaction.

To build the transaction the following information will be collected first:

  • tx-in: UTXO of the address that pays for the transaction and deposit
  • tx-out: The transaction output as ADDRESS VALUE
  • invalid-hereafter: Time that transaction is valid until (in slots)
  • certificate-file: stake address registration certificate
  • fee: The fee amount in Lovelace

tx-in:​

Query the UTXO of the address that pays for the transaction and deposit:

cd $HOME/cardano-testnet/keys

cardano-cli query utxo \
    --address $(cat payment.addr) \
    --testnet-magic 1 > fullUtxo.out

The result should look like the following:

cat fullUtxo.out
>                            TxHash                                 TxIx      Amount
> ----------------------------------------------------------------------------------------
> b64ae44e1195b04663ab863b62337e626c65b0c9855a9fbb9ef4458f81a6f5ee     1      1000000000 lovelace

so in this case the required UTXO would be b64ae44e1195b04663ab863b62337e626c65b0c9855a9fbb9ef4458f81a6f5ee#1.

tx-out:​

This would be payment.addr and the amount that has to be paid. Since we don't know how much the transaction will cost we put it as 1 ADA for the moment - $(cat payment.addr)+1000000

invalid-hereafter:​

Find out the current slot:

currentSlot=$(cardano-cli query tip --testnet-magic 1 | jq -r '.slot')
echo Current Slot: $currentSlot

The invalid-hereafter value must be greater than the current tip. In this example, we use current slot + 1000 - $currentSlot+1000.

certificate:​

Create a stake address registration certificate:

cardano-cli stake-address registration-certificate \
    --stake-verification-key-file stake.vkey \
    --out-file stake.cert

witness-override:​

When calculating the fee for a transaction, the --witness-count option indicates the number of keys signing the transaction. You must sign a transaction submitting a stake address registration certificate to the blockchain using the secret key for the payment address spending the input, as well as the secret key for the stake address to register.

fee:​

Now, we build the transaction which will return the tx.raw transaction file and also the transaction fees:

cardano-cli transaction build \
    --tx-in b64ae44e1195b04663ab863b62337e626c65b0c9855a9fbb9ef4458f81a6f5ee#1 \
    --tx-out $(cat payment.addr)+1000000 \
    --change-address $(cat payment.addr) \
    --testnet-magic 1 \
    --certificate-file stake.cert \
    --invalid-hereafter $(( ${currentSlot} + 1000)) \
    --witness-override 2 \
    --out-file tx.raw

The output is the transaction fee in lovelace:

Estimated transaction fee: Lovelace 172013

Registering the stake address, not only pays transaction fees, but also includes a deposit (which you get back when deregister the key) as indicated in the protocol parameters.

The deposit amount can be found in protocol.json under stakeAddressDeposit:

cardano-cli query protocol-parameters \
    --testnet-magic 1  \
    --out-file protocol.json

stakeAddressDeposit=$(cat protocol.json | jq -r '.stakeAddressDeposit')
echo $stakeAddressDeposit

Build the transaction​

Next, the complete transaction output is calculated by subtracting the deposit and transaction fees from the amount we have in our payment address:

txOut=$((1000000000-${stakeAddressDeposit}-172013))
echo ${txOut}

Now we have all the information in place to build the final transaction file:

cardano-cli transaction build-raw \
    --tx-in b64ae44e1195b04663ab863b62337e626c65b0c9855a9fbb9ef4458f81a6f5ee#1 \
    --tx-out $(cat payment.addr)+${txOut} \
    --invalid-hereafter $((${currentSlot} + 1000)) \
    --fee 172013 \
    --certificate-file stake.cert \
    --out-file tx.raw

Sign and Submit the transaction​

Sign the transaction with both the payment and stake secret keys:

cardano-cli transaction sign \
    --tx-body-file tx.raw \
    --signing-key-file payment.skey \
    --signing-key-file stake.skey \
    --testnet-magic 1 \
    --out-file tx.signed

And submit it:

cardano-cli transaction submit \
    --tx-file tx.signed \
    --testnet-magic 1

In the next section we will register the pool metadata.

References​