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MySQL error code

MySQL error 4094

MySQL server error 4094 is ER_OPERATION_NOT_ALLOWED_WHILE_PRIMARY_CHANGE_IS_RUNNING, reported with SQLSTATE HY000.

All queries have been blocked while function 'group_replication_set_as_primary()' is executing. Please refer timeout parameter of function 'group_replication_set_as_primary()'.
Error4094
NameER_OPERATION_NOT_ALLOWED_WHILE_PRIMARY_CHANGE_IS_RUNNING
SQLSTATEHY000
GroupServer errors

Source: MySQL 8.4 Error Reference