The latest from the MySQL community

Oracle has announced that it now provides support for DRBD with MySQL – this means a single point of support for the entire MySQL/DRBD/Pacemaker/Corosync/Linux stack! As part of this, we’ve released a new white paper which steps you through everything you need to do to configure this High Availability stack. The white paper provides a step-by-step guide to installing, configuring, provisioning and testing the complete MySQL and DRBD stack, including:

• MySQL Database
• DRBD kernel module and userland utilities
• Pacemaker and Corosync cluster messaging and management processes
• Oracle Linux operating system

DRBD is an extremely popular way of adding a layer of High Availability to a MySQL deployment – especially when the 99.999% availability levels delivered by MySQL Cluster isn’t needed. …

Attached are the slides for my MySQL Connect talk Evaluating MySQL High-availability alternatives, which I will present today at 14:30 at the MySQL Connect conference.

A bit unusually I'm posting the material ahead of the talk. The point of the talk is about evaluating each alternative from your own perspective. With that in mind, if you're at the talk with your own laptop, feel free to browse the slides at your own pace from here.

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Read the original article at 10 ways I avoid trouble in database operations

1. Avoid destructive commands From time to time I’m working with new recruits and bringing them up to speed in operations. The first thing I emphasize is care with destructive commands. What do I mean here? Well there are all sorts of them. SQL commands such as DROP table & DROP database. But also TRUNCATE [...]

For more articles like these go to Sean Hull's Scalable Startups

Related posts:

1. 5 Ways to Avoid EC2 Outages
2. 7 Ways to Troubleshoot MySQL
…

Come meet Tungsten replication and clustering experts. Don't miss these 5 talks:

Managing Worldwide Data with MySQL and Continuent Tungsten by Robert Hodges Replicating from MySQL to Oracle Database and Back Again by Robert Hodges MySQL High Availability: Power and Usability by Giuseppe Maxia Lessons from Managing 500+ MySQL Instances in the Cloud by Ronald Bradford Improving Performance with

If you’re a user of MySQL Workbench then you may have noticed a pocket knife icon appear in the top right hand corner – click on that and a terminal opens which gives you access to the MySQL utilities. In this post I’m focussing on the replication utilities but you can also refer to the full MySQL Utilities documentation.

What I’ll step through is how to uses these utilities to:

• Set up replication from a single master to multiple slaves
• Automatically detect the failure of the master and promote one of the slaves to be the new master
• Introduce the old master back into the topology as a new slave and then promote it to be the master again

Tutorial Video

Before going through the steps in detail here’s a demonstration of the replication utilities in action…

To get full …

In the Matrix movie there is a scene where the heroes visit a spiritual councelor, and amongst the people in her waiting room they see a little boy, dressed like a buddhist monk, who can bend a spoon just by looking at it. When they ask him what he does to bend the spoon, the boy's answer is: "There is no spoon". And if you watch the movie to the end, you will see that he is right. (In that spirit, if this post is too long to read for you, just skip to the last paragraph for the answer.)

The title for this blog post is of course inspired by Baron's "Is automated failover the root of all evil?", which is a commentary on GitHub's detailed explanation of their recent Pacemaker-induced downtime. Baron makes a good question, but the …

High availability is about more than just making sure that applications can get to your data, even if there is a failure:

How about when you are upgrading your database schema What if you need to add memory to a database server or reconfigure/restart MySQL If your apps want to read data from a MySQL slave, how can you be sure they are not reading stale data without re-coding your apps What

Oracle is the most powerful database system in the world. However, Oracle's expensive and complex replication makes it difficult to build highly available applications or move data in real-time to data warehouses and popular databases like MySQL.

In this webinar you will learn how Continuent Tungsten solves problems with Oracle replication at a fraction of the cost of other solutions and

Suddenly your application starts throwing "error 157" and performance degrades or is non-existing. It is easy to panic then and try all sorts of actions to get past the problem. We have seen several users doing:

• rolling restart
• stop cluster / start cluster

because they also see this in the error logs:

120828 13:15:11 [Warning] NDB: Could not acquire global schema lock (4009)Cluster Failure

That is not a really a nice error message. To begin with, it is a WARNING when something is obviously wrong. IMHO, it should be CRITICAL. Secondly, the message ‘Cluster Failure’ is misleading.  The cluster may not really have failed, so there is no point trying to restart it before we know more.

So what does error 157 mean and what can we do about it?

By using perror we can get a hint what it means:

$ …

MySQL data rules the cloud, but recent experience shows us that there's no substitute for maintaining copies of data, across availability zones, when it comes to Amazon Web Services (AWS) data resilience.

In this video (recording of our 8/23/12 webcast), we survey technologies for maintaining real-time copies of your data and the pros & cons of each. We conclude with a live demonstration of a