mysql binlog file size stop growing I made a master(A)-slave(B)-slave(C) mode MySQL instances for backup. But today when I see whether the mode works fine, I find A and B are OK. That is B can get binlog from A, but B does not write updates to its binlog. So C cannot sync with B. 

After some investigation, I see that B's new binlog file is 120 bytes and there are not any errors in MySQL's log. The sql_log_bin is ON. So I don't know what can be the reason that causes the problem. What I can supply as an addition is that the new binlog's create time is when I made a mysqldump on B. So I guess there may be some relationship between the mysqldump event and the binlog write event? Hopefully someone can help me out, thanks a lot.



B's master status:

mysql&gt; show master status;
+-----------------+----------+--------------+------------------+-------------------+
| File            | Position | Binlog_Do_DB | Binlog_Ignore_DB | Executed_Gtid_Set |
+-----------------+----------+--------------+------------------+-------------------+
| mysqlbin.000016 |      120 |              |                  |                   |
+-----------------+----------+--------------+------------------+-------------------+


B's binlog file size status:

ll /data/mysql/
-rw-rw----. 1 mysql mysql        166 7月   7 02:00 mysqlbin.000015
-rw-rw----. 1 mysql mysql        120 7月   7 02:00 mysqlbin.000016
-rw-rw----. 1 mysql mysql        288 7月   7 02:00 mysqlbin.index


B's mysqldump SQL:

mysqldump --master-data=2 --all-databases --flush-logs --user=xxx  --socket=/tmp/mysqld.sock -A &gt; /tmp/backup.sql
You have chain replication as

Master--> SLAVE A--> SLAVE B (Slave A is Slave of Master and Slave B is slave of Slave A)

As you told On Slave Server(A) binary log is enabled.


  You additionally need to enable log_slave_updates because a slave
  does not log to its own binary log any updates that are received from
  a master server. This option tells the slave to log the updates
  performed by its SQL thread to its own binary log.


So you need to enable log_slave_updates on Slave A.

Please have a look at Improving Replication Performance.