How-To

A practical reference for pgBackRest backup, restore, and cleanup commands for PostgreSQL. Covers manual cleanup, incremental backups, retention policies, and stanza management.

A practical walkthrough of reading node_cpu_seconds_total from the Prometheus Node exporter, calculating per-second rates, and deriving overall CPU utilization percentages across multiple machines.

A practical guide to the docker exec command, covering background execution, environment variables, interactive sessions, and working directory control. Includes real-world examples to help you get the most out of running commands inside containers.

A guide to inspecting SSL/TLS handshakes in Java applications when built-in debugging is unavailable. Includes a lightweight TLS client tool for testing certificate and handshake issues.

A minimal Java class and JAAS configuration for testing Kerberos authentication in isolation, useful when application-level debugging is too noisy to isolate the problem.

A walkthrough of using udevadm to diagnose and inspect udev rule application on a /dev/null device node. Covers the test command syntax and interprets the output for troubleshooting permission issues.