This document introduces the precheck feature provided by DM. This feature is used to detect possible errors in the upstream MySQL instance configuration when the data replication task is started.
check-task allows you to precheck whether the upstream MySQL instance configuration satisfies the DM requirements.
Upstream and downstream database users must have the corresponding read and write privileges. DM checks the following privileges and configuration automatically while the data replication task is started:
MySQL binlog configuration
binlog_format=ROW(DM only supports replication of the binlog in the ROW format)
binlog_row_image=FULL(DM only supports
The privileges of the upstream MySQL instance users
MySQL users in DM configuration need to have the following privileges at least:
The compatibility of the upstream MySQL table schema
TiDB differs from MySQL in compatibility in the following aspects:
The consistency of the sharded tables in the multiple upstream MySQL instances
The schema consistency of all sharded tables
The conflict of the auto increment primary keys in the sharded tables
The check fails in the following two conditions:
The check succeeds in other conditions except the two above.