Question on setting up MySQL replication

Portal Home > Knowledgebase > Articles Database > Question on setting up MySQL replication

Posted by chasebug, 11-07-2010, 11:09 PM
If the main or slave have a high load, will there be inconsistency in the data? What happens if the main or slave server goes down from an outage? If there are inconsistent data, how do you make them consistent?
Posted by drspliff, 11-07-2010, 11:20 PM
How long of an outage the slave can sustain while still being able to recover depends on how long binlogs are kept on the master. e.g. if you keep 4 hours of binlogs on the master and the slave goes down for 6 hours then you'll have to do a full re-sync and ship all the data over again. If either the master or the slave slow down too much (e.g. too much I/O, or not enough bandwidth to ship the bin-logs fast enough) then this creates replication lag where the slaves binlog position is behind the master, over time this can end up with the same problem I mentioned above - where the slave is so far behind the master that the master no longer has the binlogs for that period...
Posted by david510, 11-08-2010, 08:33 AM
You can use the DRBD + High Availability for realizing a failover system. The mysql data directory and conf file path should be clustered.