Upgrade a single instance to 4.3

This section describes how to upgrade a single Neo4j instance.

Prerequisites

Ensure that you have completed all tasks on the Upgrade checklist.

Prepare for the upgrade

  1. Install the Neo4j version that you want to upgrade to. For more information on how to install the distribution that you are using, see Operations Manual → Installation.

  2. Replace the neo4j.conf file with the one that you have prepared in section Prepare a new neo4j.conf file to be used by the new installation.

  3. Set dbms.allow_upgrade=true to allow automatic store upgrade.

  4. Set dbms.mode=SINGLE. This enables the automatic upgrade of the system database schema, as the setting dbms.allow_single_automatic_upgrade is true by default when dbms.mode=SINGLE.

  5. Copy all the files used for encryption, such as private key, public certificate, and the contents of the trusted and revoked directories (located in <neo4j-home>/certificates/).

  6. Restore each of your databases and transactions in the new installation, including the system database, by either using neo4j-admin restore (online) or neo4j-admin load (offline), depending on your backup approach. If you are running a Debian/RPM distribution, you can skip this step.

    If your old installation has modified configurations starting with dbms.directories.* or the setting dbms.default_database, verify that the new neo4j.conf file is configured properly to find these directories.

  7. If you are using custom plugins, make sure they are updated and compatible with the new version, and place them in the /plugins directory.

Upgrade your instance

  1. Start the instance by running the following command from <neo4j-home>:

    bin/neo4j start

    The upgrade takes place during startup.

  2. Monitor the neo4j.log file for information on how many steps the upgrade involves and how far it has progressed.

Post-upgrade tasks

  1. When the upgrade finishes, open the neo4j.conf file and set dbms.allow_upgrade=false. If, for some reason, you have forgotten to enable the automatic upgrade of the system database schema, use the following commands to manually upgrade it:

    • CALL dbms.upgradeStatus() to determine whether an upgrade is necessary or not.

    • CALL dbms.upgrade() on the system database to perform the upgrade of the system schema. For more details, see Operations Manual 4.3 → Procedures.

  2. Restart the instance by running the following command from <neo4j-home>:

    bin/neo4j restart

  3. It is good practice to make a full backup immediately after the upgrade.

  4. Check the default settings on all metrics. Any specific metrics that you want to be enabled must be specified in the metrics.filter. For more information, see Operations Manual → Enable metrics logging.