( Replication Implementation

Info Catalog ( Replication Intro ( Replication ( Replication Implementation Details
 6.2 Replication Implementation Overview
 MySQL replication is based on the master server keeping track of all
 changes to your databases (updates, deletes, and so on) in the binary
 logs. Therefore, to use replication, you must enable binary logging on
 the master server.   Binary log.
 Each slave server receives from the master the saved updates that the
 master has recorded in its binary log, so that the slave can execute the
 same updates on its copy of the data.
 It is *very important* to realize that the binary log is simply a
 record starting from the fixed point in time at which you enable binary
 logging. Any slaves that you set up will need copies of the databases on
 your master as they existed at the moment you enabled binary logging on
 the master. If you start your slaves with databases that are not the
 same as what was on the master *when the binary log was started*, your
 slaves may fail.
 One way to copy the master's data to the slave is to use the `LOAD DATA
 FROM MASTER' statement.  Be aware that `LOAD DATA FROM MASTER' is
 available only as of MySQL 4.0.0 and currently works only if all the
 tables on the master are `MyISAM' type. Also, this statement acquires a
 global read lock, so no updates on the master are possible while the
 tables are being transferred to the slave. When we implement lock-free
 hot table backup (in MySQL 5.0), this global read lock will no longer
 be necessary.
 Due to these limitations, we recommend that at this point  you use
 `LOAD DATA FROM MASTER' only if the dataset on the master is relatively
 small, or if a prolonged read lock on the master is acceptable. While
 the actual speed of `LOAD DATA FROM MASTER' may vary from system to
 system, a good rule of thumb for how long it will take is 1 second per
 1MB of data.  That is only a rough estimate, but you should get close
 to it if both master and slave are equivalent to 700MHz Pentium
 performance and are connected through a 100MBit/s network.
 After the slave has been set up with a copy of the master's data, it
 will simply connect to the master and wait for updates to process. If
 the master goes away or the slave loses connectivity with your master,
 it will keep trying to connect periodically until it is able to
 reconnect and resume listening for updates. The retry interval is
 controlled by the `--master-connect-retry' option. The default is 60
 Each slave keeps track of where it left off. The master server has no
 knowledge of how many slaves there are or which ones are up to date at
 any given time.
Info Catalog ( Replication Intro ( Replication ( Replication Implementation Details
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