Steven Kohrs blog | Open Source Experts

Decoding Cisco Discovery Protocol (CDP) packets

Submitted by Steven Kohrs on Thu, 11/03/2011 - 08:24.

This how-to enables you to filter network traffic for a single
packet of Cisco Discovery Protocol (CDP). The CDP packet
contains information about the switch port you are connected to,
and Wireshark and Ethereal will decode this information for you.

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NVIDIA driver automation

Submitted by Steven Kohrs on Fri, 05/13/2011 - 07:46.

My current project calls for 300+ RHEL 5 Workstations with NVIDIA Quadro GPUs. Unfortunately, the open source nouveau driver doesn't support the specific graphics card. The client did not want to manually recompile a third-party driver every time the kernel was updated. My solution was to wrap the native NVIDIA installer in a RPM with post and triggerin scripts.

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AutoYaST Post-Install Script Order

Submitted by Steven Kohrs on Wed, 05/26/2010 - 16:45.

A big part of customizing a SUSE Linux server install is to use post-install scripts, for example, to disable IPV6, correct Postfix null client settings, install third-party RPMS, and automatically register the device within a ZLM system. After a frustrating trial and error session, I learned that these scripts are ran in alphabetical order and not in the order that the scripts are defined in the AutoYaST XML file.

To enforce my will upon the install process, I now name the scripts with a numeric prefix, i.e. 001_disable_ipv6.sh, 002_fix_postfix.sh, etc.

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CUPS: Advanced Network Printing

Submitted by Steven Kohrs on Tue, 03/09/2010 - 10:44.

I've spent the past week developing an automated printer discovery and configuration solution that took me deep into the world of CUPS. This involved extensive use of the CUPS CLI, Perl, and raw socket programming.

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ZLM Lessons Learned: Part I

Submitted by Steven Kohrs on Mon, 02/15/2010 - 11:49.

I recently had the opportunity to deploy another Novell ZENWorks Linux Management (ZLM) system that manages 7000 (yes, seven thousand) Linux servers and workstations. Here are some lessons that I learned:

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