Disaster is really inevitable. Even with all the redundant power investments, ThePlanet (formerly EV1 and RackShack), had to shut down their backup generators at their H1 data center on the instructions of the fire crew. This happened after a wire-short in fault transformer led to an explosion that knocked off one of their walls, ultimately bringing 9,000 servers down. Luckily no one was injured.

This just goes on to show that just because a data center has redundant power and backup generators, it does not mean that a disaster cannot happen. IIRC, ThePlanet's last disaster was blamed on backup generators not kicking off properly.

While there was no damage to servers, I wonder how many MyISAM repairs need to be triggered once the servers do come back online?

- …

In the hot US political campaign, something of interest for MySQL is happening. The Obama camp is looking for developers in the LAMP stack, asking for MySQL experience. They also ask specifically for deep knowledge of MySQL performance and query optimization. The interesting bits about this request is that it is
It would be interesting to know what the McCain camp is going to use to counter this move. But it is not going to be so difficult to guess ...
$ wget -O /dev/null -S http://www.johnmccain.com/
...
Content-Location: http://www.johnmccain.com/Home.htm
Last-Modified: Sun, 01 Jun 2008 13:39:58 GMT
Accept-Ranges: bytes
Server: Microsoft-IIS/6.0
X-Powered-By: ASP.NET
...
I can already foresee many geeks converting a political debate into a technological challenge.
As, for me, I …

Do you use mod_auth_mysql, the Apache module that allows authentication of users to happen through a MySQL database?

If so, the nice folk at Automattic (makers of fine blogging software like Wordpress) have released a patched version that works with phpass.

With this, you can now have single sign on (SSO), with authentication against a WordPress blog (or bbPress forum). Note that WordPress (in 2.5 and later), doesn’t use MD5 hashes to store passwords any longer; instead they are salted and hashed with the phpass library. The Automattic folk use this to provide SSO for Trac and Subversion.

Read …

I just uploaded the 1.0.0 release of my MySQL templates for Cacti. Now there’s an actual download under the Downloads tab. I solved a number of issues in this release. The changelog:

2008-06-01: version 1.0.0

        * Fixed when SHOW MASTER LOGS has no File_size column.
        * Fixed Cacti-version-specific problems with include files.
        * Fixed when binary log is not enabled.
        * Fixed some caching issues.
        * Fixed make-template.pl issues when downloaded from SVN.
        * Replication graph shows only slave_lag instead of Seconds_behind_master
        * Generate a version for Cacti 0.8.6i.
        * Support generating custom versions with make-template.pl.

Cacti, monitoring, …

Michael Arrington of TechCrunch asks Twitter a few questions. I have only included a sample list below but you should read his blog post for all the questions:

• Is it true that you only have a single master MySQL server running replication to two slaves, and the architecture doesn’t auto-switch to a hot backup when the master goes down?
• Do you really have a grand total of three physical database machines that are POWERING ALL OF TWITTER?
• Is it true that the only way you can keep Twitter alive is to have somebody sit there and watch it constantly, and then manually switch databases over and re-build when one of the slaves fail?
  

A 'yes' answer to any of these questions by Twitter would be disturbing to say the least. However, …

There are some tools we commonly use doing performance review and optimization and we often ask each other where that particular stuff is located on the web or what is exactly name of the command what does that.

Initially I thought creating internal Percona Wiki page, but thought there is no reason this information should not be public instead.

So now you can find our favorite MySQL Performance Review Tools on the site.

This is just list of tools which came from the top of my head and I'm sure it is far from complete. We will extend it and we would like to hear your suggestions on what else we should add to it.

In this list we focused on Open Source tools which are helpful for "in time" performance audit - for example you see no graphing software in this list or any commercial offerings. …

Do you have skip_name_resolve set in your /etc/my.cnf? If not, consider it. DNS works fine, until it doesn't. Don't let it catch you off guard.

Do you really need to restrict MySQL users based on hostnames? If you don't, you should probably disable this feature of MySQL's authentication system. You never know when your hosting provider's DNS (or your own for that matter) will go into the toilet. And when that happens, MySQL mysteriously stops letting users log in, and all kinds of chaos ensues. Worse, it can be kind of hard to know that this is the problem, and diagnosing adds to your downtime.

Here's another scenario: DNS doesn't really fail. It just gets a little bit slow. Subtle enough that you don't really notice it, but enough to cause connection problems every now and then.

I've seen both scenarios recently when working with clients. Oh, and did I mention that not enabling skip_name_resolve actually leaves you open …

I think this is going to be really neat: you walk around the streets of San Francisco, for example, with your Android powered phone, en route to your destination 20 blocks away.

You whip out your phone, go to Google Maps, pull up the StreetView (remember this?), which zeroes in on your location using a built-in GPS, and then changes as you move the phone around using the built-in compass.

You then virtually walk the city, looking around, without actually moving an inch (looking for the closest ATM, restaurant, etc, hint-hint?).

Without further ado, let's have a look at this video from Google's I/O Conference for a demonstration?

    This video …

Today, I knocked out a couple feature requests for MySQL Forge that Giuseppe had submitted. Namely, the ability to add an avatar image to a person's profile, and also restoring the "traditional" links in the wiki top-navigation for editing, moving, deleting, watching, etc the wiki page (if you are logged in, of course).

For the avatar images, I used a web service from the Gravatar website. It's super-easy to setup. Simply grab an account on Gravatar.com for the email address you use to login to the Forge, upload your avatar image, and voilá, your avatar will be displayed on your profile page …

For all you dolphins and elePHPants out there, please take a look at MySQL Magazine's community survey, graciously produced by Mark Schoonover and B. Keith Murphy. Why bother taking the survey? Well, that's simple. It gives us insight into what you think about MySQL, what languages and platforms you use most often, and what you think about current release schedules/policies and other things. In short, you're helping to make our community better!

Please spend five minutes to take this short survey. Thanks!