- If you already upgraded: You can continue using your existing Bitcoin data directory normally. No blockchain re-download or movement of funds is required.
- If you are switching from Bitcoin Core or older Bitcoin Knots: That software may have followed the SHA256d chain. On startup, this release usually notices those extra blocks, walks back to the fork, and then downloads the BLAKE2b chain. That walk-back is only for SHA256d blocks at or after the fork. If a BLAKE2b block itself breaks the data or size rules, run
-reindexto rebuild the database from blocks you already have. Download Knots 29.4.2 from bitcoinknots.org. Other options are on the mainnet solo mining guide. Source is github.com/bitcoinknots/bitcoin. - A pruned node deletes old blocks to save disk space. If you waited so long that the walk-back blocks are already gone, or the node followed invalid blocks after a late upgrade, rebuild the node and download the chain again. This release may ask at startup whether that resync is required. If you are already pruned past 21 September 2026 when you upgrade to Knots 29.4.2, the node may need to resync from scratch; it will ask at startup if that is necessary.
- You do not need to move your bitcoin. Coins created before the fork remain spendable.
- Long coinbase maturity is active on mainnet in Knots 29.4.2. Coinbases created at height 973440 or later need 6480 confirmations (~45 days) before they can be spent in a block. Confirm with
getdeploymentinfo. Details are on the solo mining guide. - After the BIP-110 softfork, Bitcoin Core and older Bitcoin Knots still require the legacy SHA256d algorithm and follow a different blockchain.
See how it works for what happened, and the FAQ if you are pruned or unsure which software you are running. Miners using their own templates should read DATUM and Knots.