Updated MCTP send code

While the existing documentation is good, there are a couple things that have changed since it was originally written, and I had to make a couple minor adjustments to get it to work. Here’s the code to send a message. The receive part should work as originally published; what is important is the set of headers. I built and ran this on an AARCH64 platform running Fedora 38.

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Unifying Audio with Pipewire

ALSA. Jack. PulseAudio. MIDI. Musescore. Jamulus.

My musical interactions with Linux are not the most complex in the world, but they ain’t trivial. The complexity of the Linux audio landscape has been a stumbling block so far. Pipewire has just gotten me past that.

The title of this article implies that you need to do something other than install Pipewire. So far, this is not true. On my system, at least, it Just works.

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Adding an IP address to a Bridge

OpenShift requires a load balancer for providing access to the hosted applications. Although I can run a three node cluster, I need a fourth location to provide a load balancer that can then provide access to the cluster.

For my home lab set up, this means I want to run one on my bastion host….but it is already running HTTP and (FreeIPA) Red Hat IdM. I don’t want to break that. So, I want to add a second IP address to the bastion host, and have all of the existing services make use of the existing IP address. Only the new HA Proxy instance will use the new IP address.

This would be trivial for a simple Ethernet port, but I am using a Bridge, which makes it a touch trickier, but not terribly so.

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DHCP Lease Design

The key piece of persisted data in an DHCP server is the lease. A lease is a the mapping between a MAC address and an IP address, limited in time. A Lease typically has a start time and an end time, but can be renewed. Because I am still living in an IPV4 world, I have to deal with arbitrarily small pools of IP addresses. Thus, the design needs to strike the balance between static and dynamic: a machine should generally get back the same IP address each time. However, if addresses get tight, address reuse should be aggressive.

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Extract Function Refactoring using inline functions.

The Extract Function refactoring is the starting point for much of my code clean up. Once a “Main” function gets sufficiently complicated, I pull pieces of it out into their own functions, often with an eye to making them methods of the involved classes.

While working with some rust code, I encountered an opportunity to execute this refactoring on some logging code. Here’s how I executed it.

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