Monday, December 8, 2025

Linux cp command reference sheet

 

Technical cheat sheets are one of those things you don’t truly appreciate until you’re knee-deep in a problem and need the right command right now. When you’re working with Linux—especially with command-line utilities like cp—even seasoned pros can blank on syntax or flags. A good reference sheet acts like a mental shortcut, giving you instant access to the commands you use often, the ones you occasionally need, and the obscure options you’ve inevitably forgotten. Instead of digging through man pages or searching the web, you have the essentials neatly distilled into something you can scan in seconds.

Beyond convenience, cheat sheets dramatically cut down the cognitive load of technical work. Linux commands tend to pack a lot of functionality into short syntax, and remembering every flag (-r, -v, --parents, --no-clobber, etc.) isn’t a realistic expectation—especially when you're switching between tasks all day. A good cheat sheet reduces that mental juggling. It lets you focus on solving the actual problem instead of second-guessing whether you’re about to overwrite the wrong directory or miss a crucial flag that changes behavior. That reduction in friction adds up to faster, more accurate work.

There’s also an incredible amount of invisible effort that goes into creating a solid technical reference sheet. Anyone who has made one knows it’s more than “just jotting down commands.” You have to test each use case, verify edge behaviors, compare different versions of the command across distributions, and decide what’s essential enough to include. It’s a balance between completeness and usability. Too little info, and it’s pointless. Too much, and it becomes another overwhelming document no one wants to use. Curating clean, reliable, concise technical guidance takes real time, technical depth, and often several iterations.

Finally, cheat sheets become valuable assets not just for the person who creates them, but for entire teams. They help standardize how tasks are performed, reduce onboarding time for new staff, and minimize errors caused by inconsistent knowledge. When dealing with something as powerful—and potentially destructive—as Linux file operations, having a tested and trusted reference isn’t just handy; it’s a safeguard. The payoff is huge: smoother workflows, better accuracy, and a more confident technical environment. In short, technical cheat sheets are small tools with big impact.

Just click on the image to get the full screen view

From Dan Nanni www.study-notes.org




Yup, we're on Facebook, 

Sunday, December 7, 2025

📌 Packet Bookmarks in Wireshark: The Shortcut You Didn’t Know You Needed

 


When you're staring at a firehose of packets in Wireshark, trying to find that one moment in a chaotic capture can feel like decoding ancient hieroglyphics. That’s where packet bookmarks—or more accurately, sending a deliberate “ping” or identifiable packet during a trace—comes in clutch. By injecting a unique packet into the capture at the right moment, you create a visual anchor that helps you quickly zero in on the part of the traffic you actually care about, instead of scrolling endlessly like you're searching for lost treasure.

This technique is especially handy during live troubleshooting. Let’s say you’re working with a remote user and need to isolate when they clicked something, recreated a bug, or triggered a specific network event. Instead of guessing, you have them run a quick ping or curl command right when the issue occurs. That injected packet shows up as a bright, unmistakable blip in the capture. Once you find it, you’re instantly transported to the exact section of packets you need to analyze—no more hunting through thousands of frames by timestamp alone.


It also helps when multiple engineers are involved. If you're collecting captures from different vantage points—client, server, firewall—you can have everyone trigger the same “bookmark” moment. Later, when comparing traces, those bookmarks become synchronization points. This makes aligning timelines between captures a breeze and eliminates those awkward moments where you're trying to figure out why the client’s clock is three minutes off from the server’s.

Ultimately, packet bookmarks are simple, fast, and surprisingly powerful. They don't require any special Wireshark features or advanced filters—just a strategically injected, recognizable packet. Next time you're taking a trace, throw in a deliberate ping or custom packet at key moments. Your future self, scrolling through a mountain of traffic at 2 AM, will thank you.

Enjoy




Better Wi-Fi for the Hospitality Industry from Ekahau


Saturday, December 6, 2025

from the web: CISA Reports PRC Hackers Using BRICKSTORM

 

CISA Reports PRC Hackers Using BRICKSTORM for Long-Term Access in U.S. Systems


The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Thursday released details of a backdoor named BRICKSTORM that has been put to use by state-sponsored threat actors from the People's Republic of China (PRC) to maintain long-term persistence on compromised systems.

click on the image for the full article


Friday, December 5, 2025

⚠️ “Copy, Paste, Pray” — The Totally Foolproof Way to Break Everything with AI-Generated Code


There’s nothing quite like the thrill of blindly copying and pasting code from an AI model and expecting it to work perfectly on the first try. It’s the modern equivalent of buying furniture from Ikea and assuming you won’t have any screws left over. Recently, I decided to let Google AI craft a simple PowerShell script to SSH into a server and run a couple of simple commands.

 In theory, an easy task. In practice? It went about as well as trying to start a campfire with wet spaghetti.

At first glance, the script looked like it whispers, “Trust me, I know what I'm doing.” So naturally, like any responsible tech professional, I copied it, pasted it, hit Enter, and waited for magic. What I got instead was a spectacular combination of syntax errors, modules that apparently only exist in another dimension, and authentication failures so dramatic that I’m pretty sure the server judged me personally. The script didn’t “execute” so much as it “flopped politely.”

As I debugged the digital Picasso it had produced, I realized the script wasn’t even using real-world PowerShell SSH practices. It had invented its own syntax, mashed together three different module styles, and confidently referenced a function I’m 99% sure was made up on the spot. It’s like the AI had the right vibe of a script, but none of the actual functionality. Meanwhile, Google AI sat there proudly like, “You’re welcome,” while I manually rewrote the whole thing like a disappointed parent fixing a child’s science fair project made out of duct tape and crayons.

So here’s the moral of the story: AI code suggestions are great for inspiration, terrible for production, and absolutely perfect if you enjoy chaos. Don’t blindly trust them. Verify, test, tweak, and for the love of uptime, don’t assume they actually know how PowerShell works. Otherwise, you too may find yourself arguing with a server because you copy-pasted code written by a very confident, very imaginative robot author who has clearly never SSH’d into anything in its life.






Thursday, December 4, 2025

Gone with the Tide

 

My family and I once spent two weeks in Spain, where we explored some of the charming small towns along the Costa del Sol.  One of the must-see destinations was the Museo Picasso in the Andalucian city of Malaga.  Although I confess that I still don’t “get” Picasso, there was an unmistakable aura of historical importance in each of the many gallery rooms.  Great art is like a great brand, I concluded; it is unique, unmistakable and stands the test of time. You don’t need an art degree to tell the difference between a Picasso and a Monet. 


The American Marketing Association defines a brand as a "name, term, design, symbol, or any other feature that identifies one seller's good or service as distinct from those of other sellers.”  The golden arches, the Nike swoosh, that mysterious circular green siren on Starbucks cups – each connects us instantly with the unique identity of its owner.  We have come a long way from the days when a brand was a burn-scar to help us separate our cattle. 


I am old enough to remember the days when the only requirement for launching a job search was an impressive resume.  I am told that people actually studied these documents, and even made hiring decisions based on things like experience and education.  Today, serious job seekers work with a career coach, who will exhort them to “Build your brand”.  This brand is more or less unrelated to the person described in the resume, which no one reads anyway.  The implication is this; there is a completely separate existence between the public you that is being marketed, and the real, private you. 


Bestselling author Tom Peters (In Search of Excellence),  once referred to “the brand called you”,  and may have started the personal branding trend that has since been enabled by the internet.  The goal is to use Facebook, LinkedIn, Google Plus, You Tube – everything the internet has to offer -  to set yourself  apart from the herd and thoroughly impress legions of people you don’t even know. 


Your brand, experts say, is supposed to provide some form of career insurance in these uncertain times.  When I was in high school, I spent several summers pumping gas.  I was also expected to check the oil, fill the tires with air, and wash the windows.  The polite term for this position was “service station attendant”; most referred to us as “gas pump jockeys”.  In today’s lingo, if such jobs still existed, we would be branded as “petroleum placement engineers.” 


A good personal brand is much more than just a grandiose  generalization of expertise and experience, however.  It is also critical to communicate the qualities and values that you want to be known for.  To succeed in this marketplace, you will want to be branded as creative, honest, helpful, leading-edge and driven.  The ability to walk on water (or turn it into wine) would also be a plus.


Your brand, in effect, is like a sibling that stalks you wherever you go.  It is a separate identity, an alter-ego, the Jekyll to your Hyde.  In many ways, it is remarkably similar to the person we would really like to be, that we sometimes imagine to be.  We build it by carefully accumulating the evidence that supports it, while judiciously deleting the life incidents which go against it. 


This brand is a positive, life-affirming thing, until it isn’t.  As many have discovered in these challenging economic times, a personal brand, one that has taken a lifetime to create and nurture, can be washed away in a moment.  A missed promotion, a job transfer, a layoff – the environment into which our brands have evolved and prospered is mercurial and unpredictable.  Many of us have spent a lifetime building our personal brand, only to see the rules suddenly, inexplicably, and irreversibly changed. 


Jim Denevan, unlike Pablo Picasso, will never be found in a museum.  Jim brands himself as an artist who minimizes his impact on the earth.  He accomplishes this by forming his artistic creations in the sand at low tide.  Time passes, the tide comes in, and Jim’s work is automatically recycled.  While others might stress out about the quick demise of their accomplishments, he has learned to go with the tide, so to speak. 


“(Jim’s work)…was fragile and temporary.  That thing he does with sand…transient media, but they leave a memory.  They change you,” commented Frish Brandt, director of a San Francisco gallery. The artist himself had this to say.  “It’s all about the practice and not the results in a way.  There’s really no pressure at all to have a finished result, but I think it’s not so much it’s impermanent, as that there’s as much space as I can possibly use for exploring or looking around, or finding solutions, or composing… It’s much like say if someone’s walking in the wilderness and there are no roads, they can choose to go anywhere and they’re in a constant state of freedom and movement.”


Sixteen years have passed since I walked that beach in Kaanapali at sunset, and my footprints are long gone.  I remember putting them there like it was yesterday.


Author Profile - Paul W. Smith - leader, educator, technologist, writer - has a lifelong interest in the countless ways that technology changes the course of our journey through life.  In addition to being a regular contributor to NetworkDataPedia, he maintains the website Technology for the Journey and occasionally writes for Blogcritics.  Paul has over 50 years of experience in research and advanced development for companies ranging from small startups to industry leaders.  His other passion is teaching - he is a former Adjunct Professor of Mechanical Engineering at the Colorado School of Mines. Paul holds a doctorate in Applied Mechanics from the California Institute of Technology, as well as Bachelor’s and Master’s Degrees in Mechanical Engineering from the University of California, Santa Barbara.


 


 

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