How to Change the Hostname in Ubuntu Linux
You can change an Ubuntu hostname with a single command. There are two things to watch for: /etc/hosts still points to the…
The Complete pglogical Troubleshooting Guide: Architecture, Methodology, and Fixes
When pglogical stops replicating, the symptoms are often deceptively vague: rows stop appearing on the subscriber, disk space on the provider rapidly…
How to Disable cloud-init on Linux: 4 Safe Methods
Four ways to turn it off, one way to turn it down, and the trap that locks people out. You…
cloud-init Troubleshooting: 5 Silent Problems Hiding in Your Cloud VMs
Part 5 of “cloud-init Under the Hood”: ghost logs, lost seconds, and a password hiding in plain sight. You probably…
Inside /var/lib/cloud: How cloud-init Remembers What It Already Did
Part 4 of “cloud-init Under the Hood”: the cache, the markers, and the files that make reboots safe. You probably…
cloud-init and NetworkManager: Who Really Configures Your VM’s Network?
Part 3 of “cloud-init Under the Hood”: the handoff that gives your instance its IP address. You probably think cloud-init…
How cloud-init Works: The 4 Boot Stages Behind Every Cloud VM
Part 2 of a series on what cloud-init really does when your VM wakes up. You probably think cloud-init reads…
Does cloud-init Run on Every Boot? Yes, and Mostly No.
Why your bootstrap script doesn’t run twice, and the small set of things that do. You probably think cloud-init is…
How cloud-init Works on Linux: A Guide to First Boot Initialization
You created a new Linux instance. It is up. So, everything should be ready, right? Not always. I learned this…
Linux Logs Were Simple. Then systemd Changed Everything.
Why your new Ubuntu or RHEL instance doesn’t have the log files your tutorials talked about, and how to find…