This is a personal blog focused on computer software and hardware. Most
projects are implementing software and hardware for a homelab. What is a
homelab? I would say a homelab could be a single computer or dozens of
computers connected in a network. You can also integrate with computers
in the Cloud.
The primary goal of the Network UPS Tools (NUT) project is to provide support for Power Devices, such as Uninterruptible Power Supplies, Power Distribution Units, Automatic Transfer Switches, Power Supply Units and Solar Controllers. Some of those sound exciting but at this time I only have Uninterruptible Power Supplies.
My environment has 5 UPS devices connected to various servers and networking equipment. They also are not the same model or vendor. Fortunately NUT supports most consumer UPS devices that have a usb port. The goal is to use NUT to create some logic to safely shut down devices when electricity fails for an extended period. UPS devices work well with zero configuration to protect equipment from brief interruptions in power (brownouts). When the power goes out for more than a few minutes, NUT can be used to safely power down systems even if they are not all connected to the UPS via usb. NUT has a server => client configuration using a network port. This allows servers that are not connected to the UPS to respond to power outages.
Terraform is a tool for orchestrating infrastructure as code with human-readable configuration files. It can be used to create objects in the cloud and in the homelab. Similar to ansible, terraform abstracts various other APIs used to provision virtual machines, containers, or an entire public cloud ecosystem.
terraform
Terraform has an active community that contributes “providers” that interface with various resources and services. For example I will be switching my entire lab to using terraform. There are existing providers for the platforms that I use: Amazon Web Services, Docker, Kubernetes, github, proxmox, and likely more that I have yet to find.
update 2024: the official cadvisor image now supports arm which means it will work on Pis
cadvisor_logocadvisor exporter is used by Prometheus to monitor container metrics. If you are not familiar with prometheus, check out a previous post. The cadvisor program will collect metrics and make them available on a http server. Prometheus needs to be configured to collect metrics from the cadvisor exporter and then grafana can be used to visualize those metrics.
Note: I drafted this in January 2022 but I did not realize that this distro seems to be no longer maintained after SUSE acquired Rancher in 2021. I am going to upload this post because I enjoyed how flexible this distro was for running k3s.
k3OS is a Linux distribution designed to remove as much OS maintenance as possible in a Kubernetes cluster. It is specifically designed to only have what is needed to run k3s. Nodes only need to join a cluster and then all aspects of the OS can be managed from Kubernetes. Both k3OS and k3s upgrades are handled by the k3OS operator.
Blackbox exporter is used by Prometheus to monitor HTTP(S), TCP, DNS, and ICMP endpoints. If you are not familiar with prometheus, check out a previous post. The blackbox program will collect metrics and make them available on a http server. Prometheus needs to be configured to collect metrics from the blackbox exporter and then grafana can be used to visualize those metrics.
Configure blackbox
Blackbox is configured with a .yml file. The file below should be mounted inside the container. This example will monitor a HTTPS site, fail if there is no SSL/TLS encryption, using a HTTP GET request, using ipv4 protocol, allowing status codes 200 and 204, using the blackbox http prober, and will timeout after 15 seconds. This file will be in the same directory as the main prometheus config if you follow from the previous post.
