Checking Whether the expire_logs_days Value in the Source Database Is Correct

During MySQL migration, you can set expire_logs_days to change the binlog retention period. Set expire_logs_day to a proper value to ensure that the binlog does not expire before data transfer resumes. This ensures that services can be recovered after interruption.

Failure Cause

The expire_logs_days parameter of the source database is set to 0.

Handling Suggestion

If the source database is an RDS for MySQL DB instance, set expire_logs_days to a proper value by following the instructions provided in Setting a Local Retention Period for RDS for MySQL Binlogs.
If the source database is an on-premises MySQL database, perform the following steps:
1. Log in to the server where the MySQL source database is located.
2. Run the following command to check the configured binlog retention period:
```
show variables like 'expire_logs_days';
```
  Or
```
show variables like 'binlog_expire_logs_seconds';
```
3. Manually modify the my.cnf configuration file and set the binlog retention period. The following uses three days as an example.
```
expire_logs_days=3
```
  Or
```
binlog_expire_logs_seconds=259200;
```
4. After the modification, restart the source database during a non-service period.