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MySQL error code

MySQL error 4070

MySQL server error 4070 is ER_CHANGE_REP_SOURCE_GR_CHANNEL_WITH_GTID_MODE_NOT_ON, reported with SQLSTATE HY000.

When configuring a group replication channel you must do it when GTID_MODE = ON.
Error4070
NameER_CHANGE_REP_SOURCE_GR_CHANNEL_WITH_GTID_MODE_NOT_ON
SQLSTATEHY000
GroupServer errors

Source: MySQL 8.4 Error Reference