Postfix Rate Limiting: Prevent Abuse Without Blocking Real Users
Practical Postfix rate limiting: stop outbound spam and inbound floods using anvil, policyd, and sane limitsβwithout breaking legitimate mail.
Debian 13 Kdump crash capture: set it up and prove it works (case #17)
Set up kdump on Debian 13, reserve crashkernel memory, configure storage and networking, trigger safe test crashes, and verify dumps are captured.
ZFS Sequential Resilver: Why Rebuild Speed Isnβt Just βDisk MB/sβ
ZFS sequential resilver speed depends on vdev layout, recordsize, ashift, fragmentation, checksums, IOPS limits, and tunablesβnot just disk throughput.
Proxmox VM wonβt start after changing CPU type: recovery steps that work
Proxmox VM wonβt boot after changing CPU type? Diagnose QEMU/KVM failures fast, revert safely, fix flags, and prevent repeats with proven steps.
Reduced Motion Support: prefers-reduced-motion Done Properly
Ship reduced motion the right way: audit CSS/JS animations, avoid perf traps, test real settings, and prevent motion bugs from reaching production.
MySQL vs MariaDB: WooCommerce checkout lagβone setting fixes it, the other just masks it
Fix WooCommerce checkout lag by diagnosing InnoDB stalls: separate real DB tuning from placebo settings in MySQL vs MariaDB on production stacks.
BIOS Update Roulette: The Bravest Click in Computing
BIOS updates can fix security holes or brick servers. Learn safe rollout, fast diagnosis, and real commands to verify firmware, boot, and storage behavior.
Compaq and the Clone Revolution: Copying as a Business Model
How Compaq turned IBM PC cloning into an operational advantageβand what todayβs SREs can learn about compatibility, supply chains, and failure modes.
Can a GPU Last 5 Years in 2026? The Honest Answer
A practical, ops-minded guide to whether a 2026 GPU will last five years: failure modes, performance drift, thermal wear, and upgrade triggers.
Reverse DNS (PTR): Why Your Email Suffers and How to Fix rDNS Correctly
Reverse DNS (PTR) mismatches make mail look shady, break deliverability, and trigger spam filters. Learn how to check, fix, and verify rDNS safely.
Email: TLS cert renewal β keep SMTP/IMAP from breaking on renew day
A production-grade guide to renewing mail TLS certificates without breaking SMTP/IMAP: fast diagnosis, safe deploys, verification commands, and failure fixes.
Debian 13: Memory leaks in services β find them with the least disruption (case #43)
Find and confirm memory leaks on Debian 13 with minimal disruption: systemd, cgroups, smaps, eBPF, heap dumps, safe restarts, and crisp decisions.
ZFS encryption: Strong Security Without Killing Performance
Learn how to deploy ZFS native encryption with predictable performance: datasets, keys, tuning, diagnostics, and operational playbooks.
Custom checkboxes and radios with pure CSS: accessible patterns that donβt lie
Build custom checkboxes and radios using pure CSS without breaking accessibility: real patterns, failure modes, diagnostics, and production-grade checklists.
MySQL vs PostgreSQL on a 1GB RAM VPS: Whatβs Actually Usable (and the Settings That Make It)
Real settings and failure modes for running MySQL or PostgreSQL on a 1GB VPS: memory budgets, I/O limits, diagnosis steps, and sane defaults.
Docker volumes: Bind mounts vs named volumes β what survives migrations better
Learn which Docker storage option survives host migrations: bind mounts or named volumes. Includes failure modes, audits, backup steps, and diagnostics.
ZFS ACL Mapping for SMB: Avoiding Permission Nightmares
Learn how ZFS ACLs map to SMB, avoid broken inheritance and identity mismatches, and debug permissions fast with practical commands and fixes.
MariaDB vs PostgreSQL on an 8GB VPS: How to Scale Clients Safely
Practical scaling guidance for MariaDB vs PostgreSQL on an 8GB VPS: diagnose bottlenecks, set safe limits, tune memory, and grow clients without outages.
Thermal pads: the $10 fix that can change a whole GPU
A practical SRE-grade guide to GPU thermal pads: sizing, thickness, failure modes, and fast diagnosis using real commands and measurable outcomes.
Email βRecipient address rejectedβ: why valid users still bounce
A practical SRE guide to βRecipient address rejectedβ bounces: what they really mean, how to trace SMTP decisions, and how to fix them fast.
Big.LITTLE goes x86: how ARM ideas moved into PCs
A practical SRE-grade guide to x86 hybrid CPUs: what Intel P-cores/E-cores really change, how schedulers fail, and how to debug bottlenecks fast.
Slot 1 vs Socket 7: the connector war that decided your next PC
How Slot 1 and Socket 7 shaped CPU upgrades, stability, and costβand how to troubleshoot vintage boards like an SRE under pressure.
Fix Proxmox apt update Failures: DNS, Repos, and GPG Keys (Step-by-Step)
Diagnose and fix Proxmox apt update failures fast: DNS, proxy, repo setup, enterprise vs no-subscription, and GPG key errors with commands.
AMD Adrenalin: when software features matter more than silicon
AMDβs Adrenalin software can swing stability, latency, and power more than a GPU upgrade. Learn fast diagnosis, safe tuning, and failure modes.
WordPress βInvalid JSON responseβ: causes and fixes that actually work
Fix WordPress βInvalid JSON responseβ fast. Diagnose REST API failures from SSL, CORS, proxies, plugins, and caching with concrete commands and steps.
Docker βvolume is in useβ: remove or replace without data loss
Fix Docker βvolume is in useβ safely. Find what holds the volume, stop the right containers, migrate data, replace volumes, and avoid downtime.
Rspamd first-time setup: the minimal config that actually works
A production-minded Rspamd first-time setup: minimal config, sane defaults, working MTA integration, fast diagnosis, and common failure fixes.
ZFS vdev imbalance: Why One Slow VDEV Drags the Whole Pool
Learn how ZFS pool performance is limited by the slowest vdev, how imbalance happens, and a practical playbook to diagnose and fix it fast.
MariaDB vs PostgreSQL on a VPS: Tuning for Speed per Dollar
A practical SRE-grade comparison of MariaDB vs PostgreSQL on VPS: tuning, diagnostics, and failure modes to get the most speed per dollar.
MySQL vs Redis: Write-through vs Cache-asideβWhat Breaks Less in Real Apps
A practical SRE guide to MySQL+Redis caching: write-through vs cache-aside, failure modes, diagnostics, commands, and what breaks less in production.
How to Read GPU Reviews: 1080p vs 1440p vs 4K Traps
Stop buying the wrong GPU. Learn how 1080p, 1440p, and 4K benchmarks mislead, spot bottlenecks fast, and validate performance with real checks.
WordPress 504 Gateway Timeout: Is It the Database or PHP? How to Prove Which One
A production-grade method to prove whether WordPress 504s come from MySQL/MariaDB or PHP-FPM: logs, metrics, commands, and fast triage steps.
WordPress Database Bloated: wp_options Autoload Cleanup Without Breaking Things
A production-safe guide to shrink WordPress wp_options autoload bloat: diagnose, measure impact, clean safely, and prevent regressions.
Ubuntu 24.04 servers: Snap vs apt β where Snap quietly causes pain (and what to do)
On Ubuntu 24.04 servers, Snap can add latency, storage bloat, and surprise updates. Learn failure modes, fast diagnosis, and safer apt-first practices.
ZFS Mirrors: The Layout That Makes Random IO Feel Like NVMe
A practical SRE guide to ZFS mirrors: why they accelerate random reads, how to size vdevs, tune latency, diagnose bottlenecks, and avoid pitfalls.
Email: Brute force on IMAP/SMTP β lock it down without locking yourself out
Stop IMAP/SMTP brute force without breaking mail: detect attacks fast, harden auth, rate-limit, tune fail2ban, and keep admins safe.
DNS REFUSED Responses: ACLs and Policies That Block You (and How to Correct Them)
Learn why DNS servers return REFUSED, how ACLs and policies trigger it, and how to diagnose and fix resolvers and authoritative servers safely.
Proxmox systemd βDependency failedβ: Find the Service That Breaks Boot
A practical SRE playbook to trace Proxmox boot βDependency failedβ errors to the real unit, fix ordering, storage, network, and initramfs issues safely.
Debian 13: nf_conntrack table full β why connections fail and how to tune safely
When Debian 13 hits βnf_conntrack table fullβ, new connections stall or drop. Diagnose quickly, tune safely, and avoid timeouts and mystery outages.
ZFS βNo Space Leftβ Lies: Fixing Space Without Random Deletes
Diagnose why ZFS reports βno space leftβ when df looks fine: snapshots, reservations, slop space, metadata, fragmentation, and safe fixes.
Proxmox NFS timeouts: mount options that improve stability
Fix Proxmox NFS timeouts with proven mount options, kernel and network checks, and a fast diagnosis playbook built for real outages.
ECC RAM: When It Mattersβand When Itβs a Flex
ECC RAM prevents silent memory corruption that can wreck data and uptime. Learn when itβs mandatory, when itβs optional, and how to prove it.
Galaxy Note 7: the smartphone that turned airports into comedy
How the Galaxy Note 7 battery failure cascaded from design to recallβplus pragmatic ops-style lessons, diagnostics, and checklists for real teams.
Proxmox vs ESXi for ZFS: choosing the right disk controller path (HBA passthrough vs virtual disks)
For ZFS on Proxmox or ESXi, controller choice decides reliability and speed. Learn when to passthrough an HBA vs use virtual disks, with tests.
MySQL vs Percona Server: performance under spikesβwhat changes in practice
How MySQL and Percona Server behave during traffic spikes: what actually changes in flushing, replication, instrumentation, and how to diagnose fast.
Before NVIDIA: what βgraphicsβ meant when 3D was a luxury
A practical history of pre-GPU graphics: why 2D, VGA, blitters, and CPUs shaped softwareβand how to diagnose old-school bottlenecks fast.
Docker Rate Limiting and WAF in Front of Containers Without Blocking Real Users
How to add rate limiting and a WAF in front of Docker containers without blocking real users: tuning, logs, real tasks, pitfalls, and fast diagnosis.
Printers Across Offices: Fix βI Can See It But It Wonβt Printβ Over VPN
Diagnose and fix printers that appear reachable over VPN but wonβt print. Fast triage, commands, failure modes, and stable designs for offices.
ZFS Special VDEV: The Feature That Makes Metadata Fly (and Can Kill the Pool)
Learn how ZFS special vdevs accelerate metadata and small I/O, why they can become a single point of failure, and how to operate them safely.
ZFS vs mdadm: Where mdraid Wins and Where It Loses
A production-focused comparison of ZFS and mdadm: performance, failure modes, observability, and the exact commands to diagnose and recover safely.