Articles


Poetry in Production

I regularly use poetry in order to isolate development environments as I'm putting applications together. I've been happy with it, and there are a number of methods that I've developed for using poetry in various environments. For production, there are a number of different mechanisms used by people in the …

Renovating git tags

I've been very happy using Renovate (the free version) for use on my personal projects. I've previously discussed running it on one of my k8s clusters. Today, I was trying to deal with a very specific problem: I needed to track a dependency via git tags, instead of tracking the …

Sonoma Arq warning

After upgrading to Sonoma, I started occasionally (and then repeatedly) noticing warning messages and errors related to cloud files in my laptop and desktop machines in the area that is for iCloud. The specific files aren't important, although they seem to be related to applications (mostly on the phone) that …

Booting Dell servers over SMB

The first time I did this I didn't document it very well, causing the next time to be more time consuming, so her'es the rundown. It's not a secret that we use some older Dell hardware as servers in our datacenter. We've been pretty happy with it since switching away …

Exploring distroless images

Distroless images are all the rage in the container space these days due to the reduced attack surface. This is great and also results in much thinner images. But, when an image isn't behaving it can cause some additional trouble as you try to figure out what may be missing …

Flask and vault

When using dynamic database credentials with Flask, we need to make sure that the flask instance picks up the right credentials, renews them when necessary, and uses the right roles. My flask code is pretty embedded with the database changes here, so pardon the dust, but I think it's relatively …

Vault local testing setup

When I was confirming the configurations for my vault management of database credentials, I used a local postgresql and vault server. This may also be useful for development (especially testing code that may exercise the vault and database interactions). This can make it relatively easy to watch all of the …

Postgres roles and privileges

This is part of a multi-part series on using postgres databases, vault, and a variety of other tools to effect short-lived database credentials for real use. As postgres uses user and role interchangably, so will I, although I'll generally try to use user to refer to a role with login …

Django and vault

When using dynamic database credentials with Django, we need to make sure that the django instance picks up the right credentials, renews them when necessary, and uses the right roles. This post includes the background and the necessary code. Migration and creation Migration and creation provide special problems because of …

Kubernetes Load Balancer Reset

This morning I had the need to change the IP address configuration for the load balancer in our k8s cluster. The basics of changing the main pool in metallb were straightforward enough, but when I applied my changes, I didn't get what I needed. So, what happened? Originally, I wasn't …

Recovering longhorn backups

Another chapter in my learning kubernetes the hard way, this time Longhorn. Probably ill-advisedly, I'm using ephemeral volumes for my storage volumes in Longhorn and have a habit of leaving the nodes in the cluster as they're being rebuilt. Generally, this isn't a problem. This weekend, I was a bit …

Vaulting Database Credentials

Over the past year, I've been experimenting with Hashicorp Vault, using the open-source/community version for some internal experiments, including some with high availability. In a separate article, I'll go over a test configuration of Vault, but all of the notes here are agnostic to the use of HCP (Hashicorp's …

Kubernetes etcd near disaster

This post is mostly a warning to me for the future, but hopefully it'll prevent somebody else from going through the same problem. I've been running a small Kubernetes cluster for a couple of years now, mostly as an experiment and to keep my skills tuned for new tooling. Part …

Elastic index correction

Recently, I noticed a problem with my Index Lifecycle Management (ILM) not appropriately rotating indexes. The error was not super clear, but I did notice that the existing index had just reached 90 days without closing and that was the first move in the ILM. It was clear that the …

Poetry in GitLab

This weekend, I had occasion to build a new python-based utility and leaned in to my existing poetry tooling in order to do so. While starting the new project, I wanted to take advantage of some gitlab automation I'd previously used on other projects, so I figured I'd document it …

Monitor fleet aging

Background Generally speaking, I refresh most of my systems pretty regularly, spurred on by security concerns, general hygeine, a desire to make sure the automation doesn't age out, and certificate expiration. Although I don't need to refersh systems due to certificate expiration, it has historically been the easiest indicator of …

Subtasks and Redirection

Background As part of an ongoing effort to keep Cartographica up to date with recent changes in libraries that we compile from source, notably GDAL and Proj, I'm in the midst of a refresh of those subtrees in the frameworks that I build from them. Over the past few years …

fp-concat Accuracy

My previous post about proj floating point investigation discussed an issue that I'd tracked down to the OS level. However, it's clear that this relates to an underlying change to code compiled by Xcode (and/or the LLVM toolchain that it is built upon). Based on a post about Xcode …

xcodes for xcode switching

As part of digging through my various problems with Xcode 14.3 (Feedback FB12154691, FB12154887, and some test case issues involving floating point math), I needed to install Xcode 14.2 to move my buildfarm backwards. Although this didn't enitrely fix the problem, it was an essential element of the …

Proj Floating Point Error Investigation

TL;DR MacOS 13.3 or 13.3.1 incorporated a change that is affecting calculations in proj for applications running on those versions of the OS. The change appears to be relatviely subtle, only affecting a single test in a single projection and only on x86_64, not arm, but …