The client cannot connect because it does not understand a mandatory Performance Schema tracker announced by the MySQL 8.0.27+ server.
MySQL Error 2071: CR_MANDATORY_TRACKER_NOT_FOUND means the client does not recognise a mandatory Performance Schema tracker enabled on the server. Upgrade your client to MySQL 8.0.27 or newer, or disable the unknown tracker on the server to restore connectivity.
Client does not recognise tracker type %d marked as mandatory by server. CR_MANDATORY_TRACKER_NOT_FOUND was added in 8.0.27.
MySQL error 2071 appears during the initial handshake when a client binary receives a tracker type it does not understand. The server marks that tracker as mandatory, so the connection is aborted to guarantee protocol consistency.
The condition was introduced in MySQL 8.0.27, which shipped new Performance Schema connection-attribute trackers.
Clients compiled against earlier connector libraries cannot parse the new tracker code and immediately fail with this error.
An outdated client or connector that predates MySQL 8.0.27 is the primary trigger.
Older libmysqlclient, mysqlsh, JDBC, or Python connectors lack enum values for the new mandatory trackers.
The error can also surface when the server has been patched to enable custom mandatory trackers through performance_schema but the client side libraries were never updated in CI pipelines or containers.
Upgrade every client component to a version that understands tracker codes 3 and above—MySQL 8.0.27 or newer.
Rebuild applications against the updated connector to ensure symbol compatibility.
If you cannot upgrade clients immediately, disable the offending tracker on the server by turning off the relevant performance_schema_consumer variables or starting mysqld with ‑-performance-schema=off.
Docker containers pinned to mysql:8.0.25 break when they connect to a managed MySQL 8.0.34 server. Re-base the image to mysql:8.0 or install the community client 8.0.34 packages.
Legacy Java apps using Connector/J 8.0.23 fail in staging after RDS upgrades.
Bump the Maven dependency to 8.3.0 and redeploy.
Maintain client-server version parity across environments. Automate upgrades using package repositories or container tags that track the same minor version as production.
Monitor error logs for handshake failures and add health checks that alert when error 2071 appears, giving operations teams time to roll out patched clients.
Error 2054 – Authentication plugin unknown – surfaces for similar version mismatches.
Upgrading both sides usually resolves it.
Error CR_SERVER_HANDSHAKE_ERR indicates generic handshake failures. Enable protocol tracing to pinpoint whether tracker or auth plugins are at fault.
.
No, replication uses the server's internal protocol, but monitoring agents using old clients may fail and stop reporting.
Query performance_schema.setup_consumers to see which trackers are ON or MANDATORY.
Disabling restores connectivity but removes visibility for that metric. Use only as a stop-gap and re-enable after upgrading clients.
Galaxy bundles the latest MySQL client libraries in its desktop app and flags version skews, ensuring your queries run against compatible servers.
.avif)
.avif){kind=logo}
