TiDB Incremental Backup and Restore Guide
Incremental data of a TiDB cluster is differentiated data between the starting snapshot and the end snapshot of time period, and the DDLs generated during this period. Compared with full (snapshot) backup data, incremental data is smaller and therefore it is a supplementary to snapshot backup, which reduces the volume of backup data. To perform incremental backup, ensure that MVCC data generated within the specified period is not garbage collected by the TiDB GC mechanism. For example, to perform incremental backup hourly, you must set tidb_gc_life_time
to a value greater than 1 hour.
Back up incremental data
To back up incremental data, run the br backup
command with the last backup timestamp --lastbackupts
specified. In this way, br command-line tool automatically backs up incremental data generated between lastbackupts
and the current time. To get --lastbackupts
, run the validate
command. The following is an example:
LAST_BACKUP_TS=`tiup br validate decode --field="end-version" --storage "s3://backup-101/snapshot-202209081330?access-key=${access-key}&secret-access-key=${secret-access-key}"| tail -n1`
The following command backs up the incremental data between (LAST_BACKUP_TS, current PD timestamp]
and the DDLs generated during this time period:
tiup br backup full --pd "${PD_IP}:2379" \
--storage "s3://backup-101/snapshot-202209081330/incr?access-key=${access-key}&secret-access-key=${secret-access-key}" \
--lastbackupts ${LAST_BACKUP_TS} \
--ratelimit 128
--lastbackupts
: The last backup timestamp.--ratelimit
: The maximum speed per TiKV performing backup tasks (in MiB/s).storage
: The storage path of backup data. You need to save the incremental backup data under a different path from the previous snapshot backup. In the preceding example, incremental backup data is saved in theincr
directory under the full backup data. For details, see URI Formats of External Storage Services.
Restore incremental data
When restoring incremental data, make sure that all the data backed up before LAST_BACKUP_TS
has been restored to the target cluster. Also, because incremental restore updates data, you need to ensure that there are no other writes during the restore. Otherwise, conflicts might occur.
The following command restores the full backup data stored in the backup-101/snapshot-202209081330
directory:
tiup br restore full --pd "${PD_IP}:2379" \
--storage "s3://backup-101/snapshot-202209081330?access-key=${access-key}&secret-access-key=${secret-access-key}"
The following command restores the incremental backup data stored in the backup-101/snapshot-202209081330/incr
directory:
tiup br restore full --pd "${PD_IP}:2379" \
--storage "s3://backup-101/snapshot-202209081330/incr?access-key=${access-key}&secret-access-key=${secret-access-key}"