Category Archives: Sysadmin

New OOM killer implementation in Linux 2.6.36

Posted on October 21, 2010 by Kamil Kisiel

As reported on Kernel Newbies, there is almost a complete rewrite of the Out Of Memory (OOM) killer algorithm in the recently-release 2.6.36 kernel. The LWN article “Another OOM killer rewrite” has a detailed explanation of the changes. The addition … Continue reading →

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Quickly check SSL certificate expiry from the command line

Posted on November 23, 2009 by Kamil Kisiel

A quick little snippet to check when an SSL certificate on a remote server is expiring: openssl s_client -connect mail.example.com:25 | openssl x509 -noout -enddate Works for any kind of SSL service, not just SMTP.

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OpenVPN + OpenLDAP

Posted on October 11, 2009 by Kamil Kisiel

Jordan’s posted a comprehensive setup guide for OpenVPN with OpenLDAP on his blog. Looks like OpenVPN is a great way to set up a simple client VPN solution, and the cost is certainly a lot lower than solutions from Cisco. … Continue reading →

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OpenSSH 10th Anniversary

Posted on October 1, 2009 by Kamil Kisiel

Today marks the 10th Anniversary of the OpenSSH project, a 100% free implementation of the SSH protocol. SSH is something we all take for granted now and it’s hard to imagine life without it. It certainly forms one of the … Continue reading →

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Bcfg2 1.0 pre3 now available

Posted on May 22, 2009 by Kamil Kisiel

Version 1.0pre3 was released today with a rather massive overhaul of the codebase. Most notably, over 10,000 lines of code were removed as the dependency on the tlslite library was dropped in favor of using the native Python SSL bindings. … Continue reading →

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Offline backups are important

Posted on May 15, 2009 by Kamil Kisiel

Just came across this article on the BBC about a popular flight simulation site that was hacked. Apparently their only means of backup was to copy the data between their two servers. Unfortunately for them, the “hackers” got in to … Continue reading →

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Bcfg2 RPMs available from openSUSE build service

Posted on May 1, 2009 by Kamil Kisiel

I’ve started building Bcfg2 RPMs using openSUSE’s build service. They’re available for most popular RPM based distros from http://download.opensuse.org/repositories/home:/kisielk/ Currently I only have builds from the 1.0.0pre2 tarball available but I’m considering also uploading some SVN snapshots in the future. … Continue reading →

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Bcfg2 0.9.6 Released!

Posted on November 17, 2008 by Kamil Kisiel

Get it while it’s hot: http://trac.mcs.anl.gov/projects/bcfg2/wiki/Download I also have an upcoming series of blog posts about managing systems with Bcfg2 in the works. Looks for it soon.

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Bcfg2 0.9.6pre3 released

Posted on October 19, 2008 by Kamil Kisiel

The 3rd prerelease of Bcfg2 0.9.6 is now available. For those not in the know, Bcfg2 is a system that: helps system administrators produce a consistent, reproducible, and verifiable description of their environment, and offers visualization and reporting tools to … Continue reading →

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Bcfg2 Now in the Gentoo Tree

Posted on July 6, 2008 by Kamil Kisiel

Bcfg2 has finally hit the official Gentoo tree. For those who don’t know, it’s a configuration management system akin to Puppet or CFEngine. However, I think Bcfg2 has many advantages over these, the biggest of which being an active development … Continue reading →

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