At times you need to install multiple MySQL instances on same machine. This article is a brief step-by-step tutorial on the subject task which is divided into the following main…

The post Install 2 MySQL Server instances replication on Windows first appeared on Change Is Inevitable.

“Show Slave Status” command has a last column “Seconds_Behind_Master”, which gives us idea about how much time slave is lagging behind master. It is an important to be considered parameter…

The post Replication slave lag monitoring using heartbeat and windows batch scripts first appeared on Change Is Inevitable.

It's been almost two months since I have posted anything on the Scale-Out Blog, as our entire team has been heads-down working on Tungsten. We now have a number of accomplishments that are worth writing articles about. Item one on that list is community builds for Tungsten clusters.

Tungsten community builds offer a bone-simple process to check out and build Tungsten clustering software. The result is a fully integrated package that includes replication, management, monitoring, and SQL routing. The community builds work for MySQL 5.0 and 5.1 and also allow you to set up basic replication from MySQL to Oracle.

Community builds do not include much logic for autonomic management, including automated failover and sophisticated rules that keep databases up and running rain or shine. Those and other features like floating IP address support are part of the …

We got good responses to the “identify this query profile” question. Indeed it indicates an SQL injection attack. Obviously a code problem, but you must also think about “what can we do right now to stop this”. See the responses and my last note on it below the original post.

Got a new one for you!

You find a system with broken replication, could be a slave or one in a dual master setup. the IO thread is still running. but the SQL thread is not and the last error is (yes the error string is exactly this, very long – sorry I did not paste this string into the original post – updated later):

“Could not parse relay log event entry. The possible reasons are: the master’s binary log is corrupted (you can check this by running ‘mysqlbinlog’ on the binary log), the slave’s relay log is corrupted (you …

First time I heard about Galera on Percona Performance Conference 2009, Seppo Jaakola was presenting "Galera: Multi-Master Synchronous MySQL Replication Clusters". It was impressed as I personally always wanted it for InnoDB, but we had it in plans at the bottom of the list, as this is very hard to implement properly.
The idea by itself is not new, I remember synchronous replication was announced for SolidDB on MySQL UC 2007, but later the product was killed by IBM.

So long time after PPC 2009 there was available version mysql-galera-0.6, which had serious flow, to setup a new node you had to take down whole cluster. And all this time Codership ( company that develops Galera) was working on 0.7 release that introduces node propagation keeping cluster online. You can play with 0.7pre release by yourself …

  I was debugging some repl delay monitoring metrics and I noticed that the test I was doing (sysbench --test=oltp prepare) to generate replication data was far outstripping the slave.  The SQL thread was caught up to the IO thread, but the IO thread was way behind the master.       Replicating from:           a2.db.bcp.re1.yahoo.com     Master:                     a2_db_bcp_re1.000166/138395515     Slave I/O:          Yes     a2_db_bcp_re1.000165/802640907  ???     Slave Relay:        Yes     a2_db_bcp_re1.000165/802030586  596K   198 secs  

  In this case, the I/O thread was getting further and further behind as sysbench did bulk inserts into my master.  My theory …

This Thursday (October 22nd, 13:00 UTC), Walter Heck (of Open Query) will present Dual Master Setups With MMM. MMM (Multi-Master Replication Manager for MySQL) is a set of flexible scripts to perform monitoring/failover and management of MySQL master-master replication configurations (with only one node writable at any time). Session slides (PDF).

The toolset also has the ability to read balance standard master/slave configurations with any number of slaves, so you can use it to move virtual IP addresses around a group of servers depending on whether they are behind in replication. For more
information, see mysql-mmm.org.

For MySQL University sessions you point your browser …

This Thursday (October 22nd, 13:00 UTC), Walter Heck will present Dual Master Setups With MMM. MMM (Multi-Master Replication Manager for MySQL) is a set of flexible scripts to perform monitoring/failover and management of MySQL master-master replication configurations (with only one node writable at any time). The toolset also has the ability to read balance standard master/slave configurations with any number of slaves, so you can use it to move virtual IP addresses around a group of servers depending on whether they are behind in replication. For more information, see http://mysql-mmm.org/.

For MySQL University sessions, point your browser …

This Thursday (October 22nd, 13:00 UTC), Walter Heck will present Dual Master Setups With MMM. MMM (Multi-Master Replication Manager for MySQL) is a set of flexible scripts to perform monitoring/failover and management of MySQL master-master replication configurations (with only one node writable at any time). The toolset also has the ability to read balance standard master/slave configurations with any number of slaves, so you can use it to move virtual IP addresses around a group of servers depending on whether they are behind in replication. For more information, see http://mysql-mmm.org/.

For MySQL University sessions, point your browser …

This Thursday (October 22nd, 13:00 UTC), Walter Heck will present Dual Master Setups With MMM. MMM (Multi-Master Replication Manager for MySQL) is a set of flexible scripts to perform monitoring/failover and management of MySQL master-master replication configurations (with only one node writable at any time). The toolset also has the ability to read balance standard master/slave configurations with any number of slaves, so you can use it to move virtual IP addresses around a group of servers depending on whether they are behind in replication. For more information, see http://mysql-mmm.org/.

For MySQL University sessions, point your browser …