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Linux

By Greg Nowak, 22 May, 2026

OpenSSH 10 Crypto Changes: Why Old SFTP Integrations Need a Cleanup Plan

OpenSSH 10 removes DSA and warns on non-post-quantum key exchange. Here is how to scope SFTP cleanup without weakening every SSH connection.

Tags

  • OpenSSH
  • SFTP
  • SSH
  • Linux
  • Automation
By Greg Nowak, 10 February, 2022

Delete Files and Folders Older Than X days

find /[FOLDER_NAME]/* -mtime +[OLDER_THAN_DAYS] -exec rm -rf {} \;

Example deletes all files and folders in tmp folder that are older than 180 days: find /tmp/* -mtime +180 -exec rm -rf {} \;

Tags

  • bash
  • Script
  • Linux
By Greg Nowak, 23 September, 2021

Ubuntu Logs Journalctl and Dmesg

You can see a lot of good information for debugging and fixing errors on your Ubuntu server with journalctl and dmesg

journalctl --since "1 days ago"

journalctl --since "10 hours ago"

journalctl --since "12 hours ago" -p 3 -x --utc --no-pager

dmesg | less

dmesg -H --time-format iso| less

Resources:

https://unix.stackexchange.com/questions/50098/linux-network-troublesho…

Tags

  • Linux
  • logistics
  • Script
By Greg Nowak, 23 September, 2021

WordPress Cron: When It’s Time to Replace WP-Cron with Server Cron

Learn when traffic-triggered WP-Cron stops being good enough, how to switch to server cron safely, and how to verify scheduled WordPress work.

Tags

  • wordpress
  • WP-CLI
  • Linux
  • Operations
By Greg Nowak, 22 September, 2021

Bash Find and Delete Files Older Than X Days

find [FOLDER_NAME]/* -prune -mtime +14 -exec rm {} \;

Tags

  • Script
  • Linux
By Greg Nowak, 24 August, 2021

How to Flush the DNS Cache on Ubuntu Linux

Flush Ubuntu’s DNS cache safely, identify the resolver actually in use, and verify website, email, or API cutovers without guessing.

Tags

  • Ubuntu
  • Linux
  • DNS
  • Operations
By Greg Nowak, 11 August, 2021

Remove whoopsie-upload

sudo systemctl stop apport
sudo systemctl stop whoopsie 
sudo systemctl disable apport
sudo systemctl disable whoopsie
sudo aptitude purge apport whoopsie

Source: https://askubuntu.com/questions/1245078/woopsie-upload-all-process-cons…

Tags

  • Linux
By Greg Nowak, 11 August, 2021

SystemD Notes Tips and Tricks

A nice little guide: https://tecadmin.net/run-shell-script-as-systemd-service/

Tags

  • Linux
  • Script
By Greg Nowak, 10 August, 2021

Skype For Linux Fix High CPU Consumption

Possible fix:

Delete the cache: ~/.config/skypeforlinux/Cache/

Skype start command: nice -n 19 rm -r ~/.config/skypeforlinux/Cache/* ; nice -n 19 /usr/bin/skypeforlinux %U skypeforlinux --disable-accelerated-video-decode=true

Skype start command vanilla: /usr/bin/skypeforlinux %U

Tags

  • Linux
By Greg Nowak, 8 August, 2021

Linux Browser Tweaks

In firefox I have enabled a couple of tweaks described here for hardware acceleration: https://askubuntu.com/questions/1216192/why-is-kubuntu-using-much-more-…

 

Maybe more info here: https://itectec.com/ubuntu/ubuntu-why-is-kubuntu-using-much-more-cpu-th…

Tags

  • Linux

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Illustrated infographic summarizing: One Timeout, Two Orders: Make AI Actions Safe to Retry
One Timeout, Two Orders: Make AI Actions Safe to Retry
2026-07-25

A timed-out AI action may already have succeeded. Stable keys, durable ledgers, queues and stored results prevent a routine retry from duplicating real work.

Illustrated infographic summarizing: Your AI Visibility Dashboard Needs a Methodology, Not More Charts
Your AI Visibility Dashboard Needs a Methodology, Not More Charts
2026-07-24

A practical framework for measuring AI-search visibility with fixed prompts, repeated tests, separate metrics, retained evidence, and honest reporting.

Illustrated infographic summarizing: AI Admin APIs Are Here—But Your Directory Is Still the Source of Truth
AI Admin APIs Are Here—But Your Directory Is Still the Source of Truth
2026-07-23

New AI admin APIs can automate access and spend controls, but reliable governance still starts with authoritative directory data and clear ownership.

Illustrated infographic summarizing: OpenAI Presence Arrived—But Is Your Workflow Ready for an Agent?
OpenAI Presence Arrived—But Is Your Workflow Ready for an Agent?
2026-07-22

Before an AI agent can take on real work, its workflow needs clear scope, permissions, handoffs, evaluation cases, and production monitoring.

Illustrated infographic summarizing: Chatbot Transcripts Quietly Became a Retention and Redaction Problem
Chatbot Transcripts Quietly Became a Retention and Redaction Problem
2026-07-21

Chatbot transcripts spread across providers, logs and support tools. Here is how to map each copy, redact sensitive data and test deletion properly.

Illustrated infographic summarizing: Cloudflare Service Keys Stop in September: Find Every Caller
Cloudflare Service Keys Stop in September: Find Every Caller
2026-07-20

Cloudflare Service Keys stop working on September 30, 2026. Here is how to find every caller, move to scoped API tokens and avoid a late outage.

Illustrated infographic summarizing: Your AI Workflow Needs an Acceptance Test Before It Meets Customers
Your AI Workflow Needs an Acceptance Test Before It Meets Customers
2026-07-19

A practical way to test AI workflows using realistic scenarios, tool checks, human rubrics, regression suites, and clear release gates.

Three cover candidates for The Goats Were Load-Bearing fanned on a dark background: an ember-lit door, three slow knocks, and a founders' ledger
The Goats Were Load-Bearing: a fantasy where the bill always comes due
2026-07-19

A teaser for the upcoming darkly comic fantasy novel The Goats Were Load-Bearing — a village, a door that must stay poor, and the worst possible time to sell the herd. Readers pick the cover.

Vegan Power game: the yellow player catches falling fruit while a chicken and a cow look on
Vegan Power: The Little Game About Eating Fruit, Not Friends
2026-07-19

Vegan Power is a free browser game where you catch fruit, dodge the animals, protect seven hearts, and chase a better high score.

KotobaMon title screen: the Japanese logo コトバモン over a low-poly 3D island with monsters, cherry-blossom trees and a trainer.
KotobaMon: Shipping a 3D Browser Game With No Build Step and Self-Hosted Voice
2026-07-19

A look at fantasy.grn.dk, a browser-based 3D game that teaches Japanese with no build step, procedural art and self-hosted AI voice, and what its constraints show about shipping interactive products fast and cheap.

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