Process Rollback
1. Function Description
A process rollback is a rollback at the process level. Service must be stopped for process rollback at a specified storage process. First, stop both the primary and standby processes of the Tcapsvr storage process where the storage process is rolled back, then fetch the cold backup files and Ulog files of the process, construct data locally in Tcapsvr, and finally replace the constructed data files and start the Tcapsvr storage process.
2. Application Scenarios
Process rollback needs to stop the service, which interrupts TcaplusDB read and write operations. It is generally applicable to full-service rollback. At present, the online usage rate of TcaplusDB is not high, because the service should be stopped.
3. Instructions
Prepare the rollback time.
Find the application entry of the process rollback on the TcaplusDB Console.
After the application, go to the rollback transaction page according to the pop-up guide, and click the transaction execution after confirmation.
The first step in the transaction is to stop the storage processes that need to be rolled back and download the cold backup files and Ulog files of the storage processes to the storage machine to construct the data. After the data construction is complete, replace the constructed data file to the data directory, and then start the storage process where the tables are located.
4. Notations
Limitations on use:
If the table included in the process to be rolled back has been changed or deleted between the backup time point and the rollback time point, the process cannot be rolled back.
If the table included in the process to be rolled back has been expanded and shrunk between the backup time point and the rollback time point, the process cannot be rolled back.