polar-node // runbooks

Origin

Fri, 19 Jun 2026 13:49:04 +0200

From a Reel-to-Reel tape machine to Linux Infrastructure: A journey of curiosity, learning, and sharing

My journey into technology started with a question.

Not a question about programming, networking, or computers. It started with an old reel-to-reel tape machine and a thought I could not ignore:

How does this actually work? I was fascinated by the idea that something could appear simple on the outside while hiding a complex world underneath. I wanted to understand what was happening inside, how the pieces connected, and why things worked the way they did.

HA Apache Guacamole — Nginx + MariaDB Galera Cluster (IaC)

Fri, 19 Jun 2026 00:00:00 +0000

Status: in progress.

A resilient remote-access gateway built so that no single component — web tier, application tier, or database — is a single point of failure:

Multiple Guacamole nodes behind an Nginx load balancer, so a node failure doesn’t take down access
MariaDB Galera cluster as the authentication/connection database backend — synchronous multi-master replication, no single DB instance to lose
Session recording for connection auditing and compliance
Infrastructure as Code — the whole stack defined and reproducible, not hand-built

The interesting part of this project isn’t installing Guacamole — that’s well documented. It’s getting the Galera cluster quorum right (odd node count, proper arbitrator handling) and making sure failover at every layer — Nginx, Guacamole, and the database — actually works under a node failure, not just in theory.

Zabbix HA Cluster — Proxies + Database Cluster (IaC)

Fri, 19 Jun 2026 00:00:00 +0000

Status: in progress.

A fully redundant Zabbix monitoring stack, deployed entirely through code rather than manual configuration:

Multi-node Zabbix server cluster — native Zabbix HA nodes for server-level failover
Distributed Zabbix proxies — spread across network segments or regions for resilient, scalable data collection
Clustered database backend — the catalog/history database itself deployed as a cluster, not a single point of failure
Infrastructure as Code — the entire stack reproducible from a single set of Terraform/Ansible definitions

The goal is portability: the same IaC definitions should stand up the cluster identically whether the target is on-premise Proxmox VE, or a public cloud — AWS, Azure, or GCP. Same architecture, same automation, different provider underneath.

About

Mon, 15 Jun 2026 00:00:00 +0000

Linux Systems Administrator based in Almería, Spain.

I work with Proxmox, VMware, Zabbix, Ansible, Bacula, and AWS. This is where I document real infrastructure problems and how I solved them.

Automating Proxmox VM Template Creation with Cloud-Init

Mon, 15 Jun 2026 00:00:00 +0000

The problem

There’s something innate in some people — the drive to fix whatever is annoying. Annoying to some, but apparently default behavior for others.

Since I started my journey with Proxmox, I was amazed by its capabilities, and every release improved on that foundation. But there was trouble in this newfound paradise: one of the most repetitive tasks was creating a VM almost identical to the previous one. Same base OS, same baseline packages, same manual clicking through the same wizard.