Howto

In 2014 I wrote about the state of Linux network configuration, lamenting the proliferation of netlink libraries and how most projects hadn’t progressed past shell scripting and iproute2. I concluded that “there is a need for a good netlink library for one of the popular scripting languages.”

A decade later, that library exists. More importantly, the ecosystem has matured enough that every major language has a credible netlink option - and production systems are using them.

To compare them, I’ll use the same example throughout: create a bridge, a network namespace, and a veth pair connecting them.

Thanks to rapido, it’s become much simpler to test Linux device drivers for real PCIe devices in VMs.

The advantages of this approach are:

• the host is protected from memory corruption errors caused by buggy kernel drivers
• the PCI peripheral can be physically installed in a multi-use machine, reducing hardware & lab requirements
• debugging info is easily available
• the development cycle is short and simple - rapid even :)

New hardware for BufferUpr has arrived! I’m working on adding Wifi capability into the product and with new hardware comes new challenges. Challenge: Find a simple way to list all the network interfaces in the system, including the PCIe slot and MAC address for each. Solution: find /sys/devices/pci0…

Fedora 23 (the current release at the time of writing) ships an outdated version of SciPy that doesn’t include the spectrogram function. Installing the latest Scipy was kind-of a pain, so I thought I’d record some instructions for future-me and share it with you. These instructions install dependenc…

It was the year of 2015 and people were still developing new applications in PHP… but for those who could no longer accept the idea of installing a system-wide LAMP stack, there was a new-old fassionable thing: Containers! This is a quick howto for creating a throw-away container for messing around …

Sometimes there is good reason to talk to yourself. You might be doing a sound check, for example. Likewise, it can be useful to route IP packets between two interfaces on the same machine using an external path. One reason to do this is to test other network devices like routers or switches. For ma…

This concerns the proliferation of netlink libraries and a lack of direction and documentation. Background: I’ve configured a router with netem (see Bandwidth Throttling with NetEM Network Emulation and the tc-netem man page) to test Tieline devices under various delay and loss network conditions. I…

After finally completing task 01 of the Eudyptula Challenge, I’d like to share a few things I’ve learned, without divulging any crucial details about the task or solution. tl;dr Pay attention. Patience… Maybe it’s just the timezone, but the turn-around time for a response to a submission meant that …