Docker volumes: Permission denied β UID/GID strategies that stop the pain
Stop Docker volume permission denied errors with practical UID/GID strategies, fast diagnosis, and production-ready fixes for bind mounts and named volumes.
Why 640Γ480 Felt Eternal: Standards That Wonβt Let Go
VGAβs 640Γ480 still haunts modern systems because of compatibility, EDID quirks, BIOS defaults, KVMs, and tooling. Hereβs how to debug it fast.
Port 25 Blocked: How to Send Email Anyway (Without Sketchy Hacks)
Port 25 blocked? Learn clean, reliable ways to send email using authenticated SMTP relays, 587/465, APIs, and good ops hygieneβplus diagnosis steps.
ZFS for Backups: Snapshots + Send/Receive Without Tears
A practical guide to ZFS snapshots and send/receive for reliable backups: commands, failure modes, diagnosis playbooks, and hard-won ops lessons.
MySQL vs PostgreSQL Connection Pooling: Who Needs It Earlier on a VPS
On a VPS, connection pooling can be the difference between smooth throughput and a fork bomb of sessions. Learn when MySQL or Postgres needs it first.
ZFS Replacing Disks: The Safe Workflow That Avoids Pool Drama
A production-grade ZFS disk replacement workflow: verify hardware, replace safely, monitor resilvering, and avoid the mistakes that wreck pools.
ZFS Slop Space: Why Pools Feel Full Before 100%
ZFS pools feel βfullβ early due to slop space, metadata, fragmentation, and copy-on-write. Learn fast diagnosis, commands, mistakes, and ops playbooks.
RDP Between Offices Without Open Ports: The Safe βRDP Only via VPNβ Setup
Build a secure RDP between offices using VPN only: no exposed 3389, tight routing, MFA, logs, and fast troubleshooting when users say itβs βdown.β
MikroTik IPsec IKEv2 Between Offices: How to Make It Stable (and Why It Flaps)
Stop MikroTik IKEv2 site-to-site VPN flapping. Diagnose NAT, MTU, DPD, lifetimes, routing, and crypto settings with concrete commands and fixes.
AI on the CPU: What NPUs Are and Why They Exist
A production-minded guide to NPUs: what they do, why CPUs struggle with AI, how NPUs differ from GPUs, and how to diagnose real bottlenecks fast.
ZFS quota vs reservation: The Space Control Pair You Must Understand
Learn how ZFS quotas and reservations really work, how they interact with snapshots, and how to diagnose space issues fast with practical commands.
Hyper-Threading demystified: magic threads or scheduler trickery?
Hyper-Threading explained for operators: what it really shares, when it helps or hurts, and how to diagnose CPU bottlenecks with real commands.
MariaDB vs Redis: caching patterns that speed up websites without data loss
Pick the right cache between MariaDB and Redis, avoid stale or lost data, and apply proven patterns, runbooks, and real commands to ship safely.
Undervolting GPUs: the quiet performance cheat nobody tells you
A practical SRE-grade guide to undervolting GPUs safely: higher sustained clocks, lower heat and noise, fewer throttles, and predictable stability.
WordPress Core Web Vitals: real fixes for LCP/INP/CLS
Practical WordPress fixes for Core Web Vitals: diagnose LCP, INP, and CLS with real commands, production tactics, and failure-mode thinking.
Ceph performance on Proxmox is slow: 10 checks that actually find the bottleneck
A practical Proxmox+Ceph performance triage guide: network, replication, OSD tuning, disk class, and 10 checks with commands and decisions.
MySQL vs MariaDB upgrades: how to update without nuking production
A practical, production-tested guide to upgrading MySQL or MariaDB safely: compatibility traps, rehearsals, rollback plans, and real commands to verify.
Docker Multi-Network Containers: Stop Accidental Exposure to the Wrong Network
Learn how Docker multi-network containers get exposed by accident, how to audit network paths, and how to enforce safe defaults in production.
ZFS Send Stream Compatibility: Moving Data Between Different ZFS Versions
Learn how ZFS send streams behave across versions, how to probe feature flags, pick safe stream formats, and recover when replication breaks.
ZFS Resilver vs Scrub: Stop Mixing Them Up
Scrubs verify data; resilvers rebuild redundancy. Learn what each does, how to diagnose slow runs, and the commands that prevent bad ZFS days.
Resizable BAR / SAM: the small toggle that can boost big
Resizable BAR (SAM) can unlock GPU performance or trigger weirdness. Learn what it changes, how to verify it, and how to debug fast.
Docker Compose βversion is obsoleteβ: modernize your compose file safely
Stop the βversion is obsoleteβ warning in Docker Compose without breaking prod. Learn safe migrations, diagnostics, and pitfalls with real commands.
Email deliverability: Messages land in spam β the real fixes (SPF/DKIM/DMARC done right)
Stop legitimate email from landing in spam. Diagnose SPF/DKIM/DMARC, alignment, IP and domain reputation, and fix failures with real commands.
Proxmox βqemu-img: Could not createβ: permissions, paths, and filesystem fixes that actually work
Fix Proxmox βqemu-img: Could not createβ by verifying storage paths, permissions, filesystem health, and mounts. Practical commands, outputs, decisions.
Ubuntu 24.04: IPv6 firewall forgotten β close the real hole (not just IPv4) (case #72)
Ubuntu 24.04 often filters IPv4 but leaves IPv6 exposed. Audit nftables/UFW, close v6 listeners, and verify with real dual-stack tests.
MySQL vs TiDB: MySQL Compatibility vs Operational ComplexityβWhat Youβre Signing Up For
A production-minded comparison of MySQL and TiDB: compatibility gaps, failure modes, and the operational work you inherit when you choose distributed SQL.
ZFS iSCSI: ZVOL Setup That Doesnβt Stutter Under Load
Build a ZFS-backed iSCSI ZVOL that stays smooth under load: recordsize, volblocksize, SLOG, sync, multipath, queue depth, and fast diagnosis.
Laptop GPUs: why one name can hide five performance levels
Laptop GPUs often share one model name across wildly different power limits, cooling, and memoryβcreating 2β5Γ performance swings. Learn how to verify.
Ubuntu 24.04 βConnection reset by peerβ: Prove whether itβs client, proxy, or server (case #14)
A production-grade playbook to prove where βConnection reset by peerβ originates on Ubuntu 24.04: client, proxy/LB, or serverβfast, repeatable.
Email: Authenticated relay vs direct send β pick the approach that doesnβt get you blocked
Direct send or authenticated relay? Learn the tradeoffs, failure modes, and commands to debug deliverability without getting blocked or flagged as spam.
Debian 13: Thermal throttling ruins throughput β prove it and fix cooling/power limits
Learn to prove thermal throttling on Debian 13, map it to storage throughput drops, and fix cooling, firmware, and power limits safely.
Debian 13 IRQ storms and weird latency: check irqbalance and fix interrupts
Track down Debian 13 latency spikes from IRQ storms: measure per-CPU interrupts, tune irqbalance, pin queues, and validate NIC and NVMe behavior.
Ubuntu 24.04: Secure Boot Blocks Drivers β Fix It Without Nuking Your Setup
Diagnose and fix Ubuntu 24.04 Secure Boot driver blocks: MOK enrollment, DKMS signing, NVIDIA/VBox/ZFS modules, and recovery without reinstalling.
MySQL vs Percona Server: replication stabilityβwhy ops teams switch
A production-minded deep dive into why ops teams switch from MySQL to Percona Server for steadier replication, safer failovers, and fewer surprises.
ZFS snapdir=visible: Auditing Snapshots Without Making Users Rage
How to use ZFS snapdir=visible for audits safely: commands, pitfalls, performance checks, and operational patterns that keep users calm.
Proxmox backups to PBS fail: common chunk/space errors and what to do
Fix Proxmox Backup Server failures fast: decode chunk and space errors, verify datastores, tune pruning, and prevent ZFS/EXT4 surprises in production.
Docker on Windows/WSL2 is slow: fixes that actually help
Diagnose and fix Docker-on-Windows WSL2 slowness with real commands: filesystem, mounts, CPU/memory, networking, and build caching that works.
ZFS Prefetch: The Hidden Setting Behind Cache Thrash
A practical deep dive into ZFS prefetch: how it works, when it thrashes ARC, how to diagnose fast, and how to tune safely in production.
Ubuntu 24.04: sudo is slow β DNS/hostname fixes that remove the delay (case #66)
Fix slow sudo delays on Ubuntu 24.04 by diagnosing DNS, hostname, NSS, and resolver timeouts. Fast checks, commands, and reliable fixes.
ZFS RAIDZ1: The Risk Calculation Most People Never Do
RAIDZ1 looks safe until you run the real math: rebuild time, URE risk, resilver load, and modern disk sizes. Practical commands and playbooks included.
Email: Multiple MX records β how priority really works (and common mistakes)
Learn how multiple MX records really behave, why βpriorityβ isnβt failover, and how to diagnose delivery issues with practical commands and fixes.
Tabs and Accordions Without Libraries: details/summary + Progressive Enhancement
Build tabs and accordions using native details/summary and progressive enhancement: accessible, resilient, debuggable, and fast without JS-heavy UI kits.
Email Catchβall Mailbox: Why It Ruins Deliverability (and Safer Alternatives)
Catchβall mailboxes quietly wreck deliverability by amplifying spam, harming reputation, and masking bounces. Hereβs how to diagnose, fix, and replace them.
ZFS zpool iostat -v: Finding the One Disk Thatβs Ruining Latency
Learn to use zpool iostat -v to pinpoint the single slow disk, interpret latency signals, and make fixes that actually reduce ZFS tail latency.
Modern CSS Holy Grail Layout: Header, Footer, Sidebar Without Hacks
Build the classic Holy Grail page layout with modern CSS Grid and Flexbox: sticky footer, fixed or fluid sidebar, no clearfix hacks, no drama.
BlackBerry and the Long Goodbye: How Keyboards Lost to Touchscreens
A practical, ops-minded postmortem of BlackBerryβs fall: why physical keyboards lost, how touch won, and what product teams should monitor first.
Ubuntu 24.04: NVMe Disappears Under Load β the Power/ASPM Settings That Often Fix It
When NVMe vanishes under load on Ubuntu 24.04, itβs often PCIe power management. Diagnose fast, then fix ASPM/APST safely and verify.
MySQL vs MariaDB: the βdefaultβ choice that secretly slows your VPS
On small VPSes, the wrong MySQL/MariaDB default can waste IOPS and RAM. Learn fast diagnosis steps, commands, and safe fixes that stick.
Proxmox βpmxcfs is not mountedβ: why /etc/pve is empty and how to recover
Fix Proxmox βpmxcfs is not mountedβ when /etc/pve is empty. Diagnose corosync, quorum, mounts, and recover configs safely on single or cluster nodes.
Docker OOM in Containers: The Memory Limits That Prevent Silent Crashes
Learn how Docker memory limits, cgroups, and the OOM killer interact, and how to diagnose, prevent, and survive container OOMs in production.