PTR, HELO, and Matching the SMTP Hostname
Receivers reject mail when PTR, HELO, and the A record disagree. Align the hostname, reverse DNS, and Postfix myhostname before you send mail.
Email8 min read
NetBay journal
Guides for operators
Practical guides for Linux, containers, CI/CD, self-hosting, and running VPS infrastructure from Netbay Engineering.
499 articles · 24 topics
AllLinuxLinux AdministrationWindowsLinux SecurityLinux NetworkingContainersContainers & OrchestrationKubernetesCI/CDGitHubSelf-HostingBackups & DataDatabasesApp DeploymentDNS & TLSObservabilityEmailAI AgentsAI InfrastructureAPI & AutomationProxiesCloud ArchitectureHardware & PerformanceDevOps Practices
Build a Multi-Model Router Cheap Model First
Send easy prompts to a cheap model and escalate only when a classifier, token budget, or failed JSON parse says the expensive model is worth it.
AI Infrastructure8 min read
Deploying Next.js on Your Own VPS with PM2 and Nginx Reverse Proxy
Run next start under PM2 on a loopback port, keep it alive across reboots, and put Nginx in front with the proxy headers Next.js expects to see.
App Deployment7 min read
Reusable Workflows: Sharing CI Logic Across Repositories
Factor repeated pipeline logic into reusable GitHub Actions workflows with typed inputs and secrets, and share one tested CI definition across repositories.
GitHub8 min read
php.ini Knobs: Memory, Uploads, and Opcache
Tune the few php.ini knobs that matter in production: memory_limit, upload sizes, and opcache, so a 2 GB VPS serves PHP without swap or silent upload failures.
App Deployment8 min read
Writing Custom systemd Unit Files for Your Own Applications
Learn the [Unit], [Service], and [Install] sections, pick the right Type=, and ship a production-ready unit file for your own application on any modern distro.
Linux Administration6 min read
Code Review That Feeds the Pipeline: PR Checks Worth Gating On
Pick the pull-request checks that actually protect a branch, and wire them into CI so review stops shipping known-bad merges.
CI/CD6 min read
Exposing Self-Hosted Apps Safely with Caddy
Use Caddy for automatic TLS, http-to-https redirects, and controlled exposure of internal apps without opening more than the ports you intend.
Self-Hosting7 min read
Automating PostgreSQL Backups with pg_dump and Cron
A clean cron-driven pipeline for PostgreSQL: automated pg_dump archives, per-database isolation, retention pruning, and a simple integrity audit.
Backups & Data7 min read
Ollama on Ubuntu: Install, Pull, and systemd
Install Ollama on Ubuntu 24.04, pull a small 3B GGUF-backed model, and run it under systemd on an Intel Xeon Platinum CPU VPS without a GPU.
AI Infrastructure8 min read
Restricting API Access by IP and Network Rules
Layer IP allow-lists, firewall rules, and private networking to lock down your API to a narrow trust boundary that rejects unknown strangers.
API & Automation6 min read
Connect to a Windows VPS with RDP Without Exposure
Lock RDP to known IPs, require Network Level Auth, and tunnel when needed. A public 3389 listener is not a remote-admin plan for a Windows VPS.
Windows8 min read