Игорь Олемской — практические заметки по системному администрированию Linux CentOS

Today one of my scripts prompted the #2013 MySQL error while querying a huge innoDB table (31GB in ~154million rows). Some queries worked, some just failed. Looking at the logfiles, I saw the following message: InnoDB: Page checksum 1840120551 (32bit_calc: 1224736073), prior-to-4.0.14-form checksum 1811838366 InnoDB: stored checksum 3031359782, prior-to-4.0.14-form stored checksum 1811838366 InnoDB: Page lsn [...]

Today a customer asked for automated screenshots of his website. So first thing to do was asking Google how it could be accomplished on a Linux WebServer. Most of the results referred to installing an X-Server, using Firefox and stuff. This sounded a bit tricky and quite frankly... over the top. The solution I came [...]

Все время забываю какие должны быть права поэтому сделаю заметку:
Права на домашний каталог юзера:

Каталог .ssh

authorized_keys

Hello all,

We have provisioned a new server to host our dMirr service, which provides the ‘mirrorlist’ for Yum clients.  The new server is part of a High Availability cluster providing better reliability and monitoring to ensure these services have optimal uptime.  At 3:30PM Central Time we will be changing the DNS records to point dmirr.iuscommunity.org to this new server.  The migration should not impact users and should only take roughly 5 minutes to propagate.  If you do experience any issues please reply on list, or contact ius-coredev@lists.launchpad.net.

Thank you!

—
BJ Dierkes
Linux Systems Engineer IV / [RH]acker
Infrastructure Services [Development]
Rackspace Hosting

Just a quick note for everyone who’s using FFmpeg for creating screenshots from video files. Today I noticed that FFmpeg can be VERY slow on large/long movie files, but there’s a pretty neat trick to speed up the screenshot generation. I used to create my screenshots this way: ffmpeg -i /var/www/input.mov -y -f image2 -ss [...]

В ближайший понедельник 11 октября 2010 года стартуют игры первого тура Олимпиады для unix администраторов. Огранизатор Яндекс проводит первую Олимпиаду для системных администраторов —
специалистов в области Open Source и Unix. Участники олимпиады соревнуются в умении быстро и правильно отвечать на вопросы, с которыми ежедневно сталкиваются системные администраторы Яндекса.
Офф. сайт олимпиады.

Rackspace is currently hiring for the position of Linux Engineer II, as part of the Infrastructure Services RPM Development Team.  The position is based out of San Antonio, TX (tele-commuting is not available).

Primary Responsibilities:

• Development and Maintenance of RPM Packages for Rackspace proper, as well as contributing and maintaining packages for Open Source projects such as The IUS Community Project, and Fedora/EPEL.
• Act as a point of escalation for Redhat related system level issues.
• Interface with internal departments and provide assistance with automation of software installation processes.
• Development and maintenance of utilities that help to make the lives of front line Rackers easier (Python programming).

The Ideal Candidate:

• is passionate about Linux
• still believes in Open Source, and how they and Rackspace can contribute to and better the Open Source community
• more interested in automating their daily duties than they are in completing their daily duties
• is self.motivated, self.driven, and self.determined to not only be a great engineer, but to execute tasks flawlessly
• does not believe there is such a thing as “a margin for error”, but acknowledges it’s existence and takes the necessary precautions to eliminate it (QA/testing + paranoia, etc)
• is able to voice their thoughts, ideas and opinions… and back them up consistently
• not scared to be creative
• enjoys being a jack of all trades – coder, package maintainer, sysadmin, architect, engineer, qa tester, etc
• wants to be a part of a small team of engineers and developers that have a huge impact both internally, and externally

Those interested can apply for this position at:

https://rackspace.hua.hrsmart.com/ats/js_job_details.php?reqid=5028

Rackspace Hosting is the world’s leading specialist in hosting and cloud computing. The San Antonio-based company provides Fanatical Support® to its customers, across a portfolio of IT services, including Managed Hosting and Cloud Computing. Rackspace is also the founder of OpenStack™, an open source cloud platform with broad industry support, designed to offer cloud consumers greater choice. For more information, visit http://www.rackspace.com.

Additionally, for more information about careers at Rackspace, please visit http://www.rackertalent.com.

—
BJ Dierkes
Linux Systems Engineer IV / [RH]acker
Infrastructure Services [Development]
Rackspace Hosting

Some say, node.js helps you to make your applications scale. In fact, it’s really fast and flexible. Check out this realtime browsergame, build with node.js.

Learning how to scale isn't easy without any prior experience. Nowadays you have plenty of websites like highscalability.com to get some inspiration, but unfortunately there is no solution that fits all websites and needs. You still have to think on your own and find a concept that works for your requirements. So did I.

It has been a while since we’ve updated this blog so I figured I would spend some time giving a bit of a status update on the project.  At the moment we are continuing to maintain our existing package set with the latest versions of PHP 5.2/5.3 and MySQL 5.0/5.1, etc.  Our python26 packages are in the process of being moved over to EPEL (pending package reviews) and in general are in more or less maintenance mode regarding packaging.

Our primary focus right now is on the development of our build environment.  We’ve gotten to the point now where feature requests for new packages are coming in faster than we can keep up.  Ideally we want IUS to be a community driven project where anyone can contribute and maintain packages (just like Fedora/EPEL).  Currently this isn’t possible only due to the fact that our build environment is all internal infrastructure.   We have scaled back on package development so that we can focus on getting the build environment ready for production, and getting public infrastructure setup to support community packagers.  This is all very much ‘under construction’ but is something we are getting very close to achieving.

The build environment, which I’m not naming yet until we Open Source it, will be very straight forward and easy for package maintainers to wrap their heads around.  It will provide community packagers the ability to submit builds and their resulting packages to the IUS repos directly.  Some ask, “Why not just setup a Koji instance?”.  Well, there are a number of reasons that we have chosen not to use Koji and to continue development on our own system.  One reason is that Koji is very much geared for RPM packaging only, where as we [Rackspace] have other needs for a build environment to handle source builds as well as DEB packaging and the like.  There are also a number of ‘integration’ requirements we have internally that really require the flexibility to easily build in functionality when necessary where we feel Koji might be limiting.  All in all, we feel that Koji is a great product and would not wish to steer anyone away from using or contributing to that project.  That said, it works out better for our requirements to continue development on our own project.

So... if you’ve thought at all that packaging within IUS has been lacking or we aren’t quite on top of adding new stuff to the repos… it is only because we are focussing on building out the infrastructure to allow more people to contribute to the project, and allow the project to grow at a much faster and stable rate.

For anyone interested in contributing to the project please see Contributing to IUS.