One year after Sun acquired MySQL we see the positive results of this acquisition. Things are going very well in terms of collaboration, the teams are getting closer together and share the experience and the knowledge. If you want to know how the teamwork is seen from the Sun Cluster engineers, Thorsten Frueauf and myself, you should read this.

It was interesting for us to see that this interview was well observed by MySQL customers and community members. Although the interviews were not technical, they lead to technical questions. You can get more information here.

So if you are keen to see what the MySQL community wants to know about Sun Cluster, read the blog entry about MySQL and Sun Cluster.

Detlef …

A while ago we published an interview with Detlef Ulherr and Thorsten Früauf about Solaris Cluster / OpenHA Cluster on the MySQL Developer Zone.

We received a number of followup questions from our readers, requesting more technical background information. For example, Mark Callaghan was wondering about the following:

• How is failure detection done?
• How is promotion of a slave to the master done after failure detection?
• How are other slaves failed to the new master?

I asked Detlef to elaborate some more on the technical details of this solution. Here's his very exhaustive reply, thank you very much, Detlef!

I would also like to point out that he'll be …

Last week I helped a customer setup a JBoss application against MySQL Cluster. It turns out it is not immediately obvious how you should setup our JDBC connector to do loadbalancing and failover. For instance, setting the connector up for an Master-Slave setup (with MySQL Enterprise) is well documented, but not doing the same with MySQL Cluster.

It's not really properly documented in the manual part, but I found in the changelogs, and confirmed on IRC that to do load-balancing across the SQL nodes in MySQL Cluster, you would use a different JDBC connection string with the "loadbalance" keyword added...

jdbc:mysql:loadbalance://host-1,host-2,...host-n/database

That does indeed …

Last week I helped a customer setup a JBoss application against MySQL Cluster. It turns out it is not immediately obvious how you should setup our JDBC connector to do loadbalancing and failover. For instance, setting the connector up for an Master-Slave setup (with MySQL Enterprise) is well documented, but not doing the same with MySQL Cluster.

It's not really properly documented in the manual part, but I found in the changelogs, and confirmed on IRC that to do load-balancing across the SQL nodes in MySQL Cluster, you would use a different JDBC connection string with the "loadbalance" keyword added...

jdbc:mysql:loadbalance://host-1,host-2,...host-n/database

That does indeed …

Last week I helped a customer setup a JBoss application against MySQL Cluster. It turns out it is not immediately obvious how you should setup our JDBC connector to do loadbalancing and failover. For instance, setting the connector up for an Master-Slave setup (with MySQL Enterprise) is well documented, but not doing the same with MySQL Cluster.

It's not really properly documented in the manual part, but I found in the changelogs, and confirmed on IRC that to do load-balancing across the SQL nodes in MySQL Cluster, you would use a different JDBC connection string with the "loadbalance" keyword added...

jdbc:mysql:loadbalance://host-1,host-2,...host-n/database

That does indeed …

In a lot of environments.

Peter gives a nice overview why you don't always need to invest in big fat redundant hardware.

We've tackled the topic last year already ..

Now I often get weird looks when I dare to mention that Raid is obsolete ..people fail to hear the "in a lot of environments"

Obviously the catch is in the second part, you won't be doing this for your small shop around the corner with just one machine. You'll only be doing this in an environment where you can work with a redundant array of inexpensive disks. Not with a server that has to sit in a remote and isolated location.

Next to that there are situations where you will be using raid, but not for redundancy, but for disk throughput.

For those unfamiliar with SQL Server clustering let me give you a quick blurb.  Microsoft markets SQL Server as having active-active clustering.  When most people hear active/active or clustering in the database they generally immediately think of features like Oracle Rac.  SQL Servers implementation of Active-Acitve clustering ( as of 2005 anyways ) is really a HA setup with one instance active on the A side, and a seperate unrelated instance active on the B Side.  These servers hove different ports, install directories,  and share nothing at the DB level.  A san is used with its disk presented to each node in the cluster.  Microsoft Clustering Services (MCS) is used to manage the IP take over,  handle resource transitions, etc.   The setup is really active-passive, passive-active.  This ends up confusing and even mis-leading people who are both technical and in management positions.

Why …

One year ago, we announced that we would open source the entire Solaris Cluster product suite. Today, we are delivering on that promise six months ahead of schedule by releasing over two million lines of source code for the Solaris Cluster framework!

Read the official press release and listen to a podcast with Meenakshi Kaul-Basu, Director of Availability Products at Sun.

This third, and final, source code release follows the initial open sourcing of the Solaris Cluster agents in June, 2007 and Solaris Cluster Geographic Edition in December, 2007. As with the previous releases, the …

As of today, the third, final and largest code release for Open High Availability Cluster has been made available.  This now means that all of the Open HA Cluster code is available as free software.   This will allow developers and admins to access and build complete HA solutions built on source code from the OpenSolaris project.

Right before the launch I grabbed some time with Meenakshi Kaul-Basu, the engineering director at Sun responsible for Availability products, and whose group the Open HA Cluster falls under.  Take a listen to Meenakshi's explanation of the event and her insight:

My interview with Meenakshi (9:29)  …

Brian Aker has found general agreement with his post: "The Death of Read Replication".

Arjen Lentz says "I think Brian is right...", and Frank Mash confirmed: "what Brian says about replication, caching and memcached is very true".

Just like Video killed the Radio Star it looks like maybe Memcached killed the Replication Hierarchy!

But of course, Brian and others are talking about replication for scaling reads.

In my session on PBXT next week at the conference I will be talking about how we plan …