Group Replication System Variables Note You must restore the backup to the same version of MySQL which the backup was taken from, and then perform an in-place upgrade. For instructions, see Section 2.11, “Upgrading MySQL” . •create a new group with the upgraded members, see Chapter 18,  Group Replication . In this case you need to configure a new group name on each member (because the old group is still running and using the old name), bootstrap an initial upgraded member, and then add the remaining upgraded members. •set up an asynchronous replication channel between the old group and the new group, see Section 17.1.3.4, “Setting Up Replication Using GTIDs” . Configure the older primary to function as the asynchronous replication source server and the new group member as a GTID-based replica. •Restore the backup from the older member to the new instance using  mysqlbackup . •Deploy a new server instance, which must be running the same version of MySQL as the older member where the backup was taken. •Take a backup from a member of the older group using  mysqlbackup . See Section 18.5.6, “Using MySQL Enterprise Backup with Group Replication” . •Upgrade MySQL on the new instance, see Section 2.11, “Upgrading MySQL” . Once the ongoing data missing from the newer group is small enough to be quickly transferred, you must redirect write operations to the new group. Wait until all data from the old group is propagated to the new group and then drop the asynchronous replication connection. As part of a provisioning approach you can use MySQL Enterprise Backup to copy and restore the data from a group member to new members. However you cannot use this technique to directly restore a backup taken from a member running an older version of MySQL to a member running a newer version of MySQL. The solution is to restore the backup to a new server instance which is running the same version of MySQL as the member which the backup was taken from, and then upgrade the instance. This process consists of: 18.8.3.4 Group Replication Upgrade with  mysqlbackup 18.9 Group Replication System Variables Repeat this process to create a suitable number of new instances, for example to be able to handle a failover. Then join the instances to a group based on the Section 18.8.3.3, “Group Replication Online Upgrade Methods” .‘ This section lists the system variables that are specific to the Group Replication plugin. Every configuration option is prefixed with " group_replication ". Some system variables on a Group Replication group member, including some Group Replication- specific system variables and some general system variables, are group-wide configuration settings. These system variables must have the same value on all group members, cannot be changed while Group Replication is running, and require a full reboot of the group (a bootstrap by a server with group_replication_bootstrap_group=ON ) in order for the value change to take effect. If the group has a value set for one of the system variables, and a joining member has a different value set for that system variable, the joining member cannot join the group until the value is changed to match. If the group has a value set for one of the system variables, and the joining member does not support the system variable, it cannot join the group. These conditions apply to the following system variables: • group_replication_single_primary_mode 3793