Linux / Unix Command Examples

Here are links to some useful Linux tips:

https://www.cyberciti.biz/faq/linux-unix-appleosx-bsd-cat-command-examples/

https://peteris.rocks/blog/htop/

https://www.cyberciti.biz/faq/searching-multiple-words-string-using-grep/

https://www.cyberciti.biz/faq/using-sed-to-delete-empty-lines/

https://www.cyberciti.biz/faq/linux-hide-processes-from-other-users/

https://www.cyberciti.biz/faq/bash-check-if-process-is-running-or-notonlinuxunix/

https://www.cyberciti.biz/faq/unix-linux-bsd-appleosx-bash-assign-variable-command-output/

http://unixmillenniumbug.com/

https://bash.cyberciti.biz/file-management/linux-shell-script-to-reduce-pdf-file-size/

https://www.cyberciti.biz/faq/bash-file-command-not-found-how-to-install-file/

https://www.cyberciti.biz/faq/set-up-a-basic-iptables-firewall-on-amazon-linux-ami/

https://www.cyberciti.biz/faq/fedora-redhat-centos-5-6-disable-firewall/

https://bash.cyberciti.biz/virtualization/shell-script-to-setup-an-lxd-linux-containers-vm-lab-for-testing-purpose/

https://hackertarget.com/ossec-introduction-and-installation-guide/

Awesome. VIM “for people who don’t want to use it , but have to…”. Or see my page https://www.cyberciti.biz/faq/linux-unix-vim-save-and-quit-command/

sudo is the right choice for granting admin rights on the CentOS Linux 8 server. Learn how to create a new user and grant her admin rights https://www.cyberciti.biz/faq/add-create-a-sudo-user-on-centos-linux-8/

663 Comments

  1. Tomi Engdahl says:

    https://hackaday.com/2025/03/20/linux-fu-a-warp-speed-prompt/

    Reply
  2. Tomi Engdahl says:

    https://hackaday.com/2025/04/14/linux-fu-stopping-a-runaway/

    Reply
  3. Tomi Engdahl says:

    https://www.howtogeek.com/how-linux-exit-codes-help-you-write-robust-scripts/

    Reply
  4. Tomi Engdahl says:

    https://hackaday.com/2025/05/30/what-does-linux-need-a-dial/
    https://gitlab.com/sephalon/rotary_dial_kmod

    Reply
  5. Tomi Engdahl says:

    https://hackaday.com/2025/06/11/network-infrastructure-and-demon-slaying-virtualization-expands-what-a-desktop-can-do/

    Reply
  6. Tomi Engdahl says:

    Opensource Terminal bandwidth utilization tool for Linux, macOS, Android, and Windows users and IT Professionals.

    Source code repo https://github.com/imsnif/bandwhich

    Reply
  7. Tomi Engdahl says:

    ArchiveBox is a self-hosted app that lets you preserve content from websites in a variety of formats. Without active preservation effort, everything on the internet eventually disappears or degrades. You can build your own personal archive box

    Source https://github.com/ArchiveBox/ArchiveBox

    Linkwarden is another good one

    For personal purpose, self-hosted solutions are better choices than on cloud.

    Use flask, Django, and SQL, or psql

    wget, but better?
    i think it does indexing as well. more than just wget.

    Reply
  8. Tomi Engdahl says:

    https://www.facebook.com/share/1Arb58DZCd/

    Paperless-ngx is a communitysupported opensource document management system that transforms your physical documents into a searchable online archive so you can keep, well, less paper. It is a free and opensource app

    Source https://github.com/paperless-ngx/paperless-ngx?tab=readme-ov-file

    Comments:

    I use it and really love it. It’s changed how I organize documents.

    For physical documents, I bought a ScanSnap scanner and have it configured so that when I scan a document, it’s saved to a folder on my home server (via SMB), which paperless-ngx picks up and stores, then paperless-ai generates a title and tags for it using AI. All automated just by inserting a document and clicking one button on the scanner.

    For documents where I need to keep the physical copy (like tax documents, which I need to retain for 7 years), I use stickers with QR codes and an ASN (Archive Serial Number) to automatically associate the digital copy with the physical one.

    For digital documents, I can forward them to paperless-ngx via email, or just drag and drop them into the UI (or upload them via the Android app)

    The latest version of paperless-ai added Rag (Retrieval-Augmented Generation) chat, which lets you ask questions in plain English (like “when did I install solar panels, and which company installed them?”) and it’ll find the answer from your documents. Works with local AI too.

    Been using paperless-ngx for a few years now. It might not be glamorous but it’s a solid product and works well.

    Reply
  9. Tomi Engdahl says:

    I hope they stay open source. I’ve come across a couple of good ones from 20 years ago and their transition was disappointing. Yep Knowledgetree and Alfreso

    Reply
  10. Tomi Engdahl says:

    https://www.facebook.com/share/15BDSCtkp8/

    Copyparty is a portable file server with accelerated resumable uploads, dedup, WebDAV, FTP, TFTP, zeroconf, media indexer, thumbnails++ all in one file, no deps

    Download source code https://github.com/9001/copyparty?tab=readme-ov-file

    Reply
  11. Tomi Engdahl says:

    Hurl is a CLI and opensource tool for developers and IT professionals that uses a simple text format to run and chain HTTP requests. It’s used to fetch data and test HTTP sessions by capturing values and evaluating queries on responses. Hurl works with HTML, XML, JSON, and APIs like REST, SOAP, and GraphQL.

    Download repo https://github.com/Orange-OpenSource/hurl

    Reply
  12. Tomi Engdahl says:

    dstp is a free and opensource tool that run common networking tests against your site such as ping, dns, TLS certificate validation and check for HTTP status codes for your website. It is a small tool that is useful for both developers and IT professionals. Try it out.

    Source code repo https://github.com/ycd/dstp

    Reply
  13. Tomi Engdahl says:

    Or you could use sslscan which is already in many repos. Not knocking this software, but I prefer to use software that has already been vetted by my distro or upstream (Debian)

    jpaine@Technetium:~$ sslscan http://www.example.com
    Version: 2.0.7
    OpenSSL 3.0.2 15 Mar 2022

    Connected to 23.206.229.143

    Testing SSL server http://www.example.com on port 443 using SNI name http://www.example.com

    SSL/TLS Protocols:
    SSLv2 disabled
    SSLv3 disabled
    TLSv1.0 disabled
    TLSv1.1 disabled
    TLSv1.2 enabled
    TLSv1.3 enabled

    TLS Fallback SCSV:
    Server supports TLS Fallback SCSV

    TLS renegotiation:
    Session renegotiation not supported

    TLS Compression:
    OpenSSL version does not support compression
    Rebuild with zlib1g-dev package for zlib support

    Heartbleed:
    TLSv1.3 not vulnerable to heartbleed
    TLSv1.2 not vulnerable to heartbleed

    Supported Server Cipher(s):
    Preferred TLSv1.3 256 bits TLS_AES_256_GCM_SHA384 Curve 25519 DHE 253
    Accepted TLSv1.3 256 bits TLS_CHACHA20_POLY1305_SHA256 Curve 25519 DHE 253
    Accepted TLSv1.3 128 bits TLS_AES_128_GCM_SHA256 Curve 25519 DHE 253
    Preferred TLSv1.2 256 bits ECDHE-ECDSA-AES256-GCM-SHA384 Curve P-256 DHE 256
    Accepted TLSv1.2 128 bits ECDHE-ECDSA-AES128-GCM-SHA256 Curve P-256 DHE 256
    Accepted TLSv1.2 256 bits ECDHE-ECDSA-CHACHA20-POLY1305 Curve P-256 DHE 256

    Server Key Exchange Group(s):
    TLSv1.3 128 bits secp256r1 (NIST P-256)
    TLSv1.3 128 bits x25519
    TLSv1.2 128 bits secp256r1 (NIST P-256)

    SSL Certificate:
    Signature Algorithm: ecdsa-with-SHA384
    ECC Curve Name: prime256v1
    ECC Key Strength: 128

    Subject: *.example.com
    Altnames: DNS:*.example.com, DNS:example.com
    Issuer: DigiCert Global G3 TLS ECC SHA384 2020 CA1

    Not valid before: Jan 15 00:00:00 2025 GMT
    Not valid after: Jan 15 23:59:59 2026 GMT

    Reply

Leave a Comment

Your email address will not be published. Required fields are marked *

*

*