Docker Vulnerability Scanning: What to Trust and What Is Noise
Learn what Docker scanner findings matter, whatβs mostly noise, and how to triage CVEs with SBOMs, VEX, and runtime reality using real commands.
MySQL vs PostgreSQL: βrandom timeoutsββnetwork, DNS, and pooling culprits
Chasing βrandomβ DB timeouts? Learn how MySQL and PostgreSQL differ under network, DNS, and pooling failures, with fast diagnostics and fixes.
Segfault in production: why one crash can end a quarter
A production segfault is never βjust a crash.β Learn how one memory fault cascades into outages, data loss, and missed quartersβand how to stop it fast.
AVX-512: why some love it and others fear it
AVX-512 can accelerate real workloadsβor tank latency, clocks, and scheduling. Learn what it does, how to detect it, and how to deploy safely.
MariaDB vs Percona Server: performance tweaksβwhatβs real and whatβs marketing
A production-minded look at MariaDB vs Percona Server performance claims, what actually moves latency and throughput, and how to diagnose bottlenecks fast.
ZFS HDD-only Pool Tuning: Getting Speed Without SSDs
Practical ZFS tuning for HDD-only pools: layouts, recordsize, sync, ARC, prefetch, and diagnostics to get speed without SSDs in production.
Email: Phishing from Your Domain β an Incident Response Playbook That Works
A production-grade playbook for phishing sent from your domain: diagnose fast, contain, fix SPF/DKIM/DMARC, recover deliverability, and prevent repeats.
DMARC fails: choose a policy without breaking legitimate mail
Fix DMARC failures without torching real email. Diagnose SPF/DKIM alignment, tune policy safely, and stop spoofing with staged enforcement.
‘Format C:’ and Other Commands That Ruined Weekends
A practical, ops-first guide to catastrophic commands, how they happen, and how to diagnose, prevent, and recover from them in production.
Debian 13: New interface name broke networking β stable naming fixes that survive reboots (case #67)
Debian 13 can rename NICs and strand servers offline. Diagnose fast, map MAC-to-name, and enforce stable interface naming that survives upgrades.
Debian 13 MTU/MSS Mismatch: Why Large Files Stall and How to Fix It Cleanly
Large downloads stalling on Debian 13 often means MTU or MSS mismatch. Learn fast diagnosis, packet-level proof, and clean fixes for real networks.
MySQL vs Elasticsearch for Ecommerce Search: Why SQL Collapses Under Filters
Why ecommerce filtering melts MySQL search: query plans, indexes, cardinality, and I/O. Practical diagnostics, fixes, and when Elasticsearch wins.
MySQL vs PostgreSQL Full-Text Search: When Built-In Is Enough and When Itβs a Trap
A practical SRE guide to MySQL and PostgreSQL full-text search: how it works, where it breaks, and how to diagnose performance and relevance fast.
Docker Multi-Stage Builds: Shrink Images Without Breaking Runtime
Learn how to use Docker multi-stage builds to cut image size safely, avoid runtime surprises, and diagnose failures with practical commands and checks.
Email headers: Read βReceivedβ properly β trace where delivery breaks
Learn to read email Received headers like an SRE: trace hops, spot relays, identify queue delays, and pinpoint where delivery breaks fast.
Email Blacklisted IP/Domain: How to Verify and Get Delisted the Right Way
Learn how to verify an email IP or domain blacklist, pinpoint why you were listed, fix the real cause, and request delisting without making it worse.
Docker Containers Filling Disk: tmp/log/cache Cleanup That Wonβt Burn You
Practical SRE guide to diagnose and stop Docker containers filling disk from /tmp, logs, and caches using safe cleanup, limits, and monitoring.
ZFS dRAID: Faster ResilverβOr Just Faster Complexity?
A production-minded look at ZFS dRAID: what it fixes, what it complicates, how to operate it, and how to diagnose resilver bottlenecks fast.
WordPress 429 Too Many Requests: bots, rate limits, Cloudflare β how to fix
Diagnose and fix WordPress 429 errors from bots, rate limits, WAF rules, and Cloudflare. Fast playbook, commands, and safe mitigation steps.
Migrate ESXi VM to Proxmox Without vCenter: OVF/OVA Export, Import, and Driver Fixes
Move an ESXi VM to Proxmox without vCenter: export OVF/OVA, convert disks, import to QEMU, fix drivers, networking, and boot safely.
Proxmox Linux VM Slow Disk: Controller + Cache Choices That Fix Stutter
Fix Proxmox Linux VM disk stutter by choosing the right virtio-scsi/virtio-blk controller, cache mode, iothreads, and verifying host storage.
Proxmox HA βcannot start resourceβ: finding the real blocker (quorum, storage, network)
Track down why Proxmox HA says βcannot start resourceβ by isolating the real blocker: quorum, storage locks, network splits, or stale manager state.
ZFS zfs hold: The Safety Pin That Blocks Accidental Deletion
Learn how ZFS holds protect snapshots from deletion, how they interact with send/receive and retention, and how to debug βcanβt destroyβ fast.
Chiplet GPUs: why the idea is logicalβand brutally hard
Chiplet GPUs promise better yields and scaling, but interconnect, memory coherence, scheduling, and tooling make them painfully hard in production.
Ubuntu 24.04: sudo is slow β DNS/hostname fixes that remove the delay (case #6)
Fix slow sudo on Ubuntu 24.04 by tracing DNS/hostname lookups, repairing /etc/hosts and NSS order, and validating resolvers fast.
Debian 13: fio benchmarks lie β how to test storage without fooling yourself
Stop trusting pretty fio numbers on Debian 13. Learn how caching, alignment, queue depth, and IO engines skew resultsβand how to benchmark safely.
Flash: the tech that was everywhereβuntil it vanished
Flash ran the web, then vanished under security fires, mobile bans, and open standards. Learn what broke, how to diagnose, and what to do now.
How AI Will Rewrite the Graphics Pipeline: The Frame Thatβs Half-Generated
A practical, ops-first guide to hybrid rendering: where AI generates part of each frame, and how to debug latency, VRAM, artifacts, and failures fast.
Proxmox Disks Not Detected: HBA, BIOS, and Cabling Quick Checklist
A production-grade checklist to fix Proxmox disks not detected: BIOS/HBA modes, cabling, PCIe, drivers, multipath, and ZFS-friendly sanity checks.
MySQL vs PostgreSQL on a 4GB RAM VPS: What to Set First for Websites
A practical, ops-first guide to tuning MySQL or PostgreSQL on a 4GB VPS for websites: memory, I/O, connections, caching, and fast triage.
MySQL vs ClickHouse: Stop Analytics from Killing OLTP (The Clean Split Plan)
A pragmatic blueprint to separate MySQL OLTP from ClickHouse analytics, prevent query storms, and ship reliable metrics without melting production.
SLI/CrossFire: Why Multi-GPU Was a Dreamβand Why It Died
SLI and CrossFire promised easy multi-GPU speedups, but real systems exposed latency, frame pacing, APIs, and power limits that killed the dream.
Docker Desktop Networking Weirdness: LAN Access, Ports, and DNS Fixes That Actually Work
A production-minded guide to Docker Desktop networking: why LAN access breaks, how ports map, and proven DNS fixes with fast triage commands.
Ubuntu 24.04: βFailed to get D-Bus connectionβ β fix broken sessions and services (case #48)
Fix Ubuntu 24.04 βFailed to get D-Bus connectionβ by tracing systemd, logind, XDG_RUNTIME_DIR, and bus sockets with fast commands.
RAID is not backup: the sentence people learn too late
RAID keeps disks running, not your data safe. Learn real failure modes, fast diagnosis, and a practical backup plan with commands you can run today.
ZFS Scrub Slow: How to Tell Normal Slowness From a Real Problem
Learn when a ZFS scrub is just slow versus broken. Diagnose bottlenecks fast with real commands, outputs, and fixes for common scrub failures.
Debian 13: Service wonβt start after config change β fix it by reading the right log lines (case #1)
When a Debian 13 service wonβt start after a config change, use systemd and journald to find the failing line fast and fix it safely.
Proxmox βcluster not ready – no quorum?β: restore quorum without making it worse
A practical SRE guide to diagnosing Proxmox βcluster not ready - no quorum?β and restoring quorum safely without risking split-brain or data loss.
Postfix βhost not foundβ: DNS issues that silently kill email
Track down Postfix βhost not foundβ delivery failures fast: DNS traps, resolver timeouts, caching lies, IPv6 gotchas, and a practical command-driven playbook.
Ubuntu 24.04: Reboot requiredβ¦ but you canβt reboot β smart ways to plan maintenance
Practical ways to handle βreboot requiredβ on Ubuntu 24.04 when uptime matters: fast diagnosis, safe deferral, live patching, and maintenance planning.
PostgreSQL vs SQLite: scaling pathβhow to move from file DB without downtime
A pragmatic zero-downtime path from SQLite to PostgreSQL: dual writes, change capture, cutover checks, and failure modes youβll actually hit.
DDR4 to DDR5: What Actually Makes Your System Faster (and What Doesnβt)
DDR5 can speed up memory-bound workloads, but timing, channels, BIOS settings, and NUMA often decide the winner. Measure first, upgrade second.
WordPress Duplicate Content Fix: Canonical, Trailing Slash, and WWW Without Cannibalization
Stop WordPress duplicate URLs from splitting rankings: lock canonical, trailing slash, and www rules with redirects, headers, and clean sitemaps.
ZFS ARC per TB: RAM Sizing Without Myths and Forum Religion
Stop sizing ZFS RAM by terabytes. Learn ARC behavior, workload-first sizing, fast diagnostics, and commands to decide when memory helps or hurts.
Ubuntu 24.04: Reverse path filtering β the hidden setting that breaks multi-homing (case #54)
Ubuntu 24.04 can drop perfectly valid multi-homed traffic due to reverse path filtering. Diagnose rp_filter fast and fix routing safely.
ZFS Readonly: The Anti-Ransomware Trick You Can Deploy Today
Turn ZFS readonly into a practical anti-ransomware control: immutable datasets, snapshots, and guardrails with real commands, failures, and ops playbooks.
Docker Pull Is Painfully Slow: DNS, MTU, and Proxy Fixes That Actually Work
Diagnose slow docker pull fast: DNS stalls, MTU blackholes, proxies, IPv6, registry throttles, and fixes with commands, outputs, and decisions.
Docker networks: Bridge vs host vs macvlan β pick the one that wonβt bite later
A practical guide to choosing Docker bridge, host, or macvlan networking, with failure modes, diagnostics, commands, and production-safe defaults.
Debian 13: DNS split-horizon gone wrong β fix internal names without breaking the internet (case #33)
Diagnose and fix split-horizon DNS failures on Debian 13: internal zones, systemd-resolved, caching, and safe fallbacks without breaking public DNS.
Proxmox βPermission Deniedβ in Datacenter: Roles and ACLs Done Right
Fix Proxmox Datacenter permission denied errors by understanding roles, ACL paths, privilege mapping, and audit methods with safe, repeatable checks.