In an Active Active Master Master setup there is a special procedure to do when recovering a down server.

Assumptions:

• 
  
• Your application can handle 1 of the servers being down.
  
• You?re a good DBA so you take hot backups at least once a night.
  
• You never PURGE MASTER LOGS to a point where a backup can't recover.
  
• I'm assuming that you already know how to set up a master master config. If not comment and I will post how to, and things to watch out for.
  

Recover from backup, lets assume your using ibbackup


%> ibbackup --apply-log --use-memory 2000 my.cnf.restore


my.cnf.restore contains the innodb definitions and the location of the backup files.

Once restored INNODB will actually print out the last slave position it was …

Log Buffer #11, a compendium of news from the database blogosphere has been published on Mark Rittman?s Oracle Weblog. Read the Log Buffer homepage to learn about Log Buffer and see how to get involved.

Klaus-Heiner Lehne, a German conservative MEP on the payroll of a leading patent litigation firm, is not amused at recent developments in the European Parliament, and in particular he is frustrated to see that other MEPs call for a more balanced approach to patent policy. Lehne much prefers commissioner McCreevy’s push for the EPLA, the Excessive Patent Litigation Agreement (the official long form starts with “European”, but “Excessive” would be more accurate).

The day before yesterday, Lehne vented his anger by issuing …

Stefan Hinz and the fabulous documentation team have created a documentation page that I believe will vastly simplify the lives of many a database administrator. What could this possibly be? Why, a table of all the server configuration options, of course!

That's right, check out the tables for both the 5.0 and 5.1 releases. You'll notice that both server and status variables are listed in the lengthy table. Each variable is hyperlinked to the area where you can find a description of what each of the variables does or affects. Alongside each variable are five columns indicating whether the variable is available via a command line option, the option file, is a server variable (i.e. will appear in a SHOW VARIABLES output), is a status variable (i.e. …

I tend to use MySQL from the interactive command line shell quite a bit (SSH to your db server and type the command mysql to start). I noticed today that there is a pretty extensive built in help system in this command.

You can access it by typing help COMMAND, so for instance if you type help ALTER TABLE you get a quick reference for constructing an ALTER TABLE statement.

If you can't remember what command you want to use, then typing help contents is your friend. It will output:

For more information, type 'help item', where item is
one of the following categories:
Administration
Column Types
Data Definition
Data Manipulation
Functions
Geographic features
Transactions

So if your looking for that command that outputs all the columns in a table, but don't know what it's called, you might now try help administration …

I'm now back from EuroOSCON 2006 which was the reason I was not posting for a while. Pretty interesting event, even though it looks like it is getting less geeky compared to OSCON in US I visited two years ago - a lot of presentations now shifted to philosophical, political and business issues. I however do not know might be this is just Europe thing.

I gave a talk on High Performance FullText Search for Database Content which is now available for download from MySQL Performance Presentations page

We have plans to turn this presentation into article to publish here with some extra information and source code for all tests …

Yesterday three groups in the European Parliament (PES, Greens/EFA, GUE/NGL) announced their motion for a resolution on patent policy. I published their press release earlier today on this Web site.

In parallel, the Independence/Democracy group in the European Parliament (commonly abbreviated as ID or IND/DEM) filed this motion for a resolution on patent policy. The motion was put forward by Tom Wise, an MEP from the UK Independence Party who spoke out in strong terms against the software patent directive.

The ID motion is materially consistent with the motion of PES, …

Nearly 100 days after the close of its JBoss acquisition, Red Hat is delivering the goods. Michael Tiemann said at OSCON that JBoss' business model was fine, but Red Hat would teach them how to really make bank with open source (my words, not his). It looks like the Red Hat model has found room for middleware siblings, as well.

As Peter Galli notes in his eWeek article:

The new Red Hat Application Stack subscription includes RHEL (Red Hat Enterprise Linux), JBoss AS (Application Server) and JBoss Hibernate, as well as support for the MySQL and PostgreSQL open-source databases.

New offerings also include JBoss subscriptions, such as JBoss AS, JBoss Hibernate and the various JEMS (JBoss Enterprise …

Three groups in the European Parliament (i.e., international-level parties) yesterday authorized me to distribute the press release below to my media contacts:

European patent controversy heating up again

PES, Greens/EFA and GUE/NGL groups in European Parliament file motion for resolution — Proposal calls for “balance between the interests of patent holders and the broader public interest in innovation and competitive markets” — Commissioner McCreevy’s preference, the EPLA, is seen as weakening EU democracy, increasing litigation costs and “exposing SMEs to greater risks” ? McCreevy to speak in parliament next week, vote to take place in mid-October