Hyperledger Besu v1.4 implements a new data structure for private state storage that is not backwards compatible. A migration will be performed when starting v1.4 for the first time to reprocess existing private transactions created using v1.3.5 or later and re-create the private state data in the v1.4 format.
Important
All nodes with existing private transactions from 1.3.5 or later will be migrated to the new private state storage when upgrading to v1.4. It is not possible to upgrade to v1.4 without migrating.
A critical issue for privacy users with private transactions created using Hyperledger Besu v1.3.4 or earlier has been identified. If you have a network with private transaction created using v1.3.4 or earlier, please read the following and take the appropriate steps:
https://wiki.hyperledger.org/display/BESU/Critical+Issue+for+Privacy+Users
Important
As a precaution (that is, resyncing should not be required), ensure your Hyperledger Besu database is backed-up or other Besu nodes in your network are available to resync from if the migration does not complete as expected.
We recommend that all nodes in a network do not upgrade and migrate at once.
To migrate, add the --privacy-enable-database-migration flag to your Besu command line options. The migration starts
automatically when this flag is specified. If you have existing private transactions and do not specify this flag,
v1.4 will not start.
After the migration starts, logs display the progress. When the migration is complete, Besu continues starting up as usual.
Do not stop the migration running once it has started. If the migration is stopped, you will need to restore your Besu database from backup and restart the migration process.
If you have a long running network with a large volume of private transactions and/or would like to discuss the migration process with us before upgrading, contact us at [email protected]