Group Replication System Variables member proceeds to the action specified by the  group_replication_exit_state_action  system variable. Up to MySQL 8.0.20, the default setting is 0, meaning that the member does not try to rejoin automatically. From MySQL 8.0.21, the default setting is 3, meaning that the member automatically makes 3 attempts to rejoin the group, with 5 minutes between each. You can specify a maximum of 2016 tries. During and between auto-rejoin attempts, a member remains in super read only mode and does not accept writes, but reads can still be made on the member, with an increasing likelihood of stale reads over time. If you cannot tolerate the possibility of stale reads for any period of time, set group_replication_autorejoin_tries  to 0. For more information on the auto-rejoin feature, and considerations when choosing a value for this option, see Section 18.7.6.3, “Auto-Rejoin” . group_replication_bootstrap_group  configures this server to bootstrap the group. This system variable must  only  be set on one server, and  only  when starting the group for the first time or restarting the entire group. After the group has been bootstrapped, set this option to  OFF . It should be set to  OFF both dynamically and in the configuration files. Starting two servers or restarting one server with this option set while the group is running may lead to an artificial split brain situation, where two independent groups with the same name are bootstrapped. 3799 Command-Line Format --group-replication-clone-threshold=# Introduced 8.0.17 System Variable group_replication_clone_threshold Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Integer Default Value 9223372036854775807 Minimum Value 1 Maximum Value 9223372036854775807 Command-Line Format --group-replication-bootstrap- group[={OFF|ON}] System Variable group_replication_bootstrap_group Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Boolean Default Value OFF • group_replication_clone_threshold • group_replication_bootstrap_group