MySQL Server's clone plugin is available from MySQL 8.0.17. If you want to use remote cloning operations for distributed recovery in a group, you must set up existing members and joining members beforehand to support this function. If you do not want to use this function in a group, do not set it up, in which case Group Replication only uses state transfer from the binary log.

To use cloning, at least one existing group member and the joining member must be set up beforehand to support remote cloning operations. As a minimum, you must install the clone plugin on the donor and joining member, grant the BACKUP_ADMIN permission to the replication user for distributed recovery, and set the group_replication_clone_threshold system variable to an appropriate level. To ensure the maximum availability of donors, it is advisable to set up all current and future group members to support remote cloning operations.

Be aware that a remote cloning operation removes user-created tablespaces and data from the joining member before transferring the data from the donor. If the operation is stopped while in progress, the joining member might be left with partial data or no data. This can be repaired by retrying the remote cloning operation, which Group Replication does automatically.