Binary logs on the master are used to transfer updates to the slave, so removing them all will break replication. Removing them at the filesystem is not ideal as you will break the internal indexing that mysql keeps, so it knows which logs it has.
the best way to clear logs down is;
- check how many log files are on the system;
mysql> show binary logs; +---------------+------------+ | Log_name | File_size | +---------------+------------+ | binlog.000001 | 1073745110 | | binlog.000002 | 1073809202 | | binlog.000003 | 1074622047 | | binlog.000004 | 1074131675 | | binlog.000005 | 1073890119 | | binlog.000006 | 1074065745 | | binlog.000007 | 1073742082 | | binlog.000008 | 1073742411 | | binlog.000009 | 190740717 | +---------------+------------+
- check the expire_logs_days variable. this variable sets the retention period of the logs in days and removes them automatically once they are older than this value. a value of 0 means ‘no expiry’.
mysql> show variables like '%expire%'; +------------------+-------+ | Variable_name | Value | +------------------+-------+ | expire_logs_days | 0 | +------------------+-------+
set the value by running the following command (2 days ;
mysql> set global expire_logs_days=2; mysql> show variables like '%expire%'; +------------------+-------+ | Variable_name | Value | +------------------+-------+ | expire_logs_days | 2 | +------------------+-------+
- to remove extra logs immediately, execute the following from within mysql after ensuring the slaves are up to date and are not lagging behind;
mysql> purge binary logs before '2012-10-27 00:00:00';
- when the log drive has completely filled, the above won’t work so then manually edit the binlog.index and remove any files you don’t want from the list and then delete them physically from the drive, bearing in mind that any replication we have going will need to read the files from the point it broke, so don’t remove them all. remove them to a point that mysql starts working again and let replication catch up. once it has, then you can purge them as much as required.