Amazon has just released their RDS Migration Tool, and Pythian has recently undertaken training to use for our clients. I wanted to share my initial thoughts on the tool, give some background on its internals, and provide a walk-through on the functionality it will be most commonly used for.

There are many factors to consider when evaluating cloud service providers, including cost, performance, and high availability and disaster recovery options. One of the most critical and overlooked elements of any cloud offering though, is the ease of migration. Often, weeks are spent evaluating all of the options only to discover after the choice is made that it will take hours of expensive downtime to complete the migration, and that there is no good rollback option in the case of failure.

In order to reduce the friction inherent in the move to a DBaaS offering, Amazon has developed an RDS Migration tool. This is an in-depth look at this new …

Interview mit Lukas und mir auf der DevOpsCon 2015 in Berlin, kurz nach dem Talk über Private Cloud mit OpenSource.

It had been in the making for long time. Google announced that Google Code would be closing, and since then the Continuent team has been hard at work to handle the transition. You can guess it: this operation would have been quicker if it had been done by a small company like we were one year ago, but being part of a large corporation introduces some constraints that have affected our schedule.

However, our wish has always been, and still is, to keep Tungsten Replicator as an open source product, with full functionalities and with the full benefits that the open source development model offers.

Today, Tungsten Replicator is available on GitHub as …

The fsfreeze command, is used to suspend and resume access to a file system. This allows consistent snapshots to be taken of the filesystem. fsfreeze supports Ext3/4, ReiserFS, JFS and XFS.

A filesystem can be frozen using following command:

# /sbin/fsfreeze -f /data

Now if you are writing to this filesystem, the process/command will be stuck. For example, following command will be stuck in D (UNINTERUPTEBLE_SLEEP) state:

# echo “testing” > /data/file

Only after the filesystem is unfreezed using the following command, can it continue:

# /sbin/fsfreeze -u /data

As per the fsfreeze main page, “fsfreeze is unnecessary for device-mapper devices. The device-mapper (and LVM) automatically freezes filesystem on the device when a snapshot creation is requested.”

fsfreeze is provided by the util-linux package in RHEL systems. Along with userspace support, fsfreeze also …

Foto: Ana Rey CC-BY-SA-2.0El “Concurso Universitario de Software Libre” (CUSL) es una iniciativa similar a la del Google Summer of Code, pero específicamente dirigida la comunidad universitaria y de estudiantes de bachillerato españoles y organizada por una grupo de Oficinas de software libre de universidades.

Como parte del esfuerzo para promover el crecimiento del ecosistema del software libre, así como introducir a talento joven en el desarrollo de aplicaciones y tecnologías libres, DBAHire.com acaba de convertirse en patrocinador plata de la competición, proporcionando recursos para los premios, gastos de …

Daniel was tracking down what appeared to be a networking problem….

• server reported 113 (No route to host)
• However, an strace did not reveal the networking stack ever returning that.
• On the other side, IP packets were actually received.
• When confronted with mysteries like this, I get suspicious – mainly of (fellow) programmers.
• I suggested a grep through the source code, which revealed  return -EHOSTUNREACH;
• Mystery solved, which allowed us to find what was actually going on.

Lessons:

1. Don’t just believe or presume the supposed origin of an error.
2. Programmers often take shortcuts that cause grief later. I fully appreciate how the above code came about, but I still think it was wrong. Mapping a “similar” situation onto an existing …

In the beginning was the MySQL command line and it was good. Verbose yes, error prone yes, and even tedious. But it was good. The UPDATE USER set SELECT_PRIV=’Y’, DROP_PRIV_’Y”, UPDATE_PRIV=’Y’,……,LAST_BLOODY_PRIV=’Y”; type errors have caught of us old timers. But it was still good.

Then came some GUI tools that were okay. Not great but they had their uses.

And then came MySQL Workbench. And it was very good.

Now there is MySQL Workbench 6.2 and it is excellent. It came out in Beta last week and has built on the proven success of its predecessors. All the usual stuff is there – Server Status, Users & Privileges, Startup/Shutdown, logs, Dashboard, Performance Reports and more. But there area whole bunch of subtle little tweaks that make it easier to use.

For instance, the VISUAL EXPLAIN allows toggling between the visual display and the tabular display. Plus you can now get query …

“There are four things that motivate open source development teams:
1. The challenge/puzzle of programming, 2. Need for the software, 3. Personal advancement, 4. Belief in open source” — Bruce Momjian.

On PostgreSQL and the challenges of motivating and managing open source teams, I have interviewed Bruce Momjian, Senior Database Architect at EnterpriseDB, and Co-founder of the PostgreSQL Global Development Group and Core Contributor.

RVZ

Q1. How did you manage to transform PostgreSQL from an abandoned academic project into a commercially viable, now enterprise relational database?

Bruce Momjian: Ever since I was a developer of database …

I wrote previously about Percona Live Santa Clara 2014, and I want to bring to your attention something Percona has done that is very nice to open source communities: have an open source appreciation day.

Its before the conference (so on Monday), and you get a choice between the CentOS Dojo (great lineup there including many from Red Hat, Monty from MariaDB, and PeterZ from Percona) or the OpenStack Today (another great lineup …

The wild and crazy guys over at S&T Geotronics, James Sanderson and Marc Tessier, have decided to go full tilt with a Kickstarter version of their DIY Open Enigma Project.  For those who missed the fanfare last year, they were featured on Instructables showing how to build an Arduino-based encryption machine that works exactly like a WWII era Enigma.  You know, the thing that Alan friggin' Turing and his team at …