Database operational contract

MySQL 8.4 group_replication_exit_state_action default OFFLINE_MODE

Failure handling/health checks observe a different node state after network partition.

MySQL 8.4Relational databaseDatabase operational contractmysql84

Agent Quick Fix

Repair against the current MySQL 8.4 contract, then keep the change narrow and source-backed.

Product: MySQL 8.4
Current-contract area: Group replication exit state default changes to OFFLINE_MODE
Likely root cause: Failure handling/health checks observe a different node state after network partition.
Repair direction: Verifier checks durability, restart, and operational safety rather than a one-shot query. Check operational state and security, not a compatibility switch that weakens the server.

Symptom

Failure handling/health checks observe a different node state after network partition.

Why This Happens

The local schema/query is valid, but upgrade path, restart behavior, replication syntax, or background operations changed in the server release.

Common Wrong Fixes

Changing local code without checking the current external contract.
Retrying the same install, build, or API call with no version/source change.
Applying a broad unsafe bypass when a narrow compatibility fix is available.

Codex Search Keywords

These are the search terms observed in a neutral Codex validation run for this failure shape.

MySQL 8.4 group_replication_exit_state_action default OFFLINE_MODE
site:dev.mysql.com group_replication_exit_state_action OFFLINE_MODE default MySQL 8.4
group_replication_exit_state_action OFFLINE_MODE default
https://dev.mysql.com/doc/refman/8.4/en/group-replication-system-variables.html
'group_replication_exit_state_action' in https://dev.mysql.com/doc/refman/8.4/en/group-replication-system-variables.html
https://dev.mysql.com/doc/refman/8.0/en/group-replication-system-variables.html
'Default Value `READ_ONLY`' in https://dev.mysql.com/doc/refman/8.0/en/group-replication-system-variables.html