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Welcome to my blog and homepage!

I’m Robin Christ, Freelance consultant specializing in network design & operations, cloud infrastructure, software development and acoustics.
I bring deep expertise in architecting modern networks using Cumulus Linux and Arista platforms, with specialized knowledge in EVPN-VXLAN fabrics and multicast in connection with AV-over-IP event networking.
My C++ development work centers on high-performance numerical computing.
In acoustics, I design loudspeaker components like Line Array waveformers, waveguides and horns using state-of-the-art multiphysics techniques.

From scalable networks over performance critical software to precision acoustic engineering: I deliver solutions that work."

Want to contact me about consulting work, feedback on a blog article or just wanna chat? Head over to Contact & PGP!

Fixing Mellanox DMI / SMBIOS Information

Introduction Cumulus Linux and the included Mellanox Hardware Management package (hw-mgmt) heavily rely on information from the BIOS DMI / SMBIOS to determine the system type / hardware configuration. If this information is wrong (or rather: incompatible), you can have all kinds of funny issues, like the fans constantly running at full speed because the ASIC temperature sensor is not initialized correctly, or the thermal control loop using wrong thresholds or PWM addresses… ...

How to mod Mellanox FRU EEPROMs under Cumulus Linux

Some OEM FRUs (fans or PSUs) for Mellanox switches may cause issues under Cumulus Linux due to OEM PNs in the EEPROMs. This guide explains how to modify the EEPROMs to resolve these issues.

Tips & Tricks for Cumulus Linux

A collection of tips and tricks for Cumulus Linux

Audio over IP Networks for Events - An Opinionated Guide, Part 2: Layer 3 Network Design Principles

The state of temporary Audio over IP Networks is poor, with large, brittle stretched VLANs and redundancy provided by Spanning Tree Protocol. This article provides an introduction to Layer 3, Routing Protocols and design principles for Layer 3 fabrics

Audio over IP Networks for Events - An Opinionated Guide, Part 1: Foundations and why L2 is considered harmful

The state of temporary Audio over IP Networks is poor, with large, brittle stretched VLANs and redundancy provided by Spanning Tree Protocol. This article covers the basic design goals for such networks and establishes why L2 should be considered harmful.

Unlocking "more" recirculation bandwidth on Arista 7050X switches

Arista 7050X series switches have some undocumented commands, which allow you to unlock “more” bandwidth for recirculation without disabling physical ports. Read about how and why.