Retiring a Stake Pool

To retire a pool we need to:

  • Create a deregistration certificate and

  • Submit the certificate to the blockchain with a transaction

The deregistration certificate contains the epoch in which we want to retire the pool. This epoch must be after the current epoch and not later than eMax epochs in the future, where eMax is a protocol parameter.

So we first need to figure out the current epoch. The number of slots per epoch is recorded in the genesis file, and we can get it with

cat mainnet-shelley-genesis.json | grep epoch
> "epochLength": 21600,

So one epoch lasts for 21600 slots. We get the current slot by querying the tip:

export CARDANO_NODE_SOCKET_PATH=relay-db/node-socket
cardano-cli shelley query tip --mainnet

> Tip (SlotNo {unSlotNo = 856232}) ...

This gives us

expr 856232 / 21600
> 39

So we are currently in epoch 39.

We can look up eMax by querying the current protocol parameters:

cardano-cli shelley query protocol-parameters \
--mainnet \
--out-file protocol.json

cat protocol.json | grep eMax
> "eMax": 100,

This means the earliest epoch for retirement is 40 (one in the future), and the latest is 139 (current epoch plus eMax).

So for example, we can decide to retire in epoch 41.

Create deregistration certificate

WARNING This involves the cold keys. Take the necessary precautions to not to expose your cold keys to the internet.

Create the deregistration certificate and save it as pool.deregistration:

cardano-cli shelley stake-pool deregistration-certificate \
--cold-verification-key-file cold.vkey \
--epoch 41 \
--out-file pool.deregistration

Draft the transaction

cardano-cli shelley transaction build-raw \
--tx-in <UTXO>#<TxIx> \
--tx-out $(cat payment.addr)+0 \
--ttl 0 \
--fee 0 \
--out-file tx.draft \
--certificate-file pool.deregistration

Calculate the fees:

cardano-cli shelley transaction calculate-min-fee \
--tx-body-file tx.draft \
--tx-in-count 1 \
--tx-out-count 1 \
--witness-count 1 \
--byron-witness-count 0 \
--mainnet \
--protocol-params-file protocol.json

For example:

> 171309

We query our address for a suitable UTxO to use as input:

cardano-cli shelley query utxo \
--address $(cat payment.addr) \
--mainnet



       TxHash             TxIx        Lovelace
------------------------------------------------
9db6cf...                    0      999999267766

We calculate our change:

expr 999999267766 - 171309
> 999999096457

Build, sign and submit the transaction:

Build the raw transaction:

cardano-cli shelley transaction build-raw \
--tx-in 9db6cf...#0 \
--tx-out $(cat payment.addr)+999999096457 \
--ttl 860000 \
--fee 171309 \
--out-file tx.raw \
--certificate-file pool.deregistration

Sign it with both the payment signing key and the cold signing key (the first signature is necessary because we are spending funds from paymant.addr, the second because the certificate needs to be signed by the pool owner):

cardano-cli shelley transaction sign \
--tx-body-file tx.raw \
--signing-key-file payment.skey \
--signing-key-file cold.skey \
--mainnet \
--out-file tx.signed

And submit to the blockchain:

cardano-cli shelley transaction submit \
--tx-file tx.signed \
--mainnet

The pool will retire at the end of epoch 40.

If we change our mind, we can create and submit a new registration certificate before epoch 41, which will then overrule the deregistration certificate.