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45 posts39 participants8 posts today
"I use Total Commander on Windows all the time. It is much better than Explorer at so many things, such as:
- Actually letting you navigate the directory structure." 
news.ycombinator.comI use Total Commander on Windows all the time. It is much better than Explorer a... | Hacker News
An author is biased.
But here's what a real network engineering manager thinks of "Networking for System Administrators." Sorry for the noise, but it was recorded in an actual data center. #n4sa2e #kickstarter #sysadmin
Top 50 Linux Commands – Quick Guide for Security & SysAdmin Pros 
Linux is the backbone of cybersecurity 
, servers 
, and DevOps 
. Mastering commands makes you faster, sharper, and more effective in troubleshooting 
, monitoring 
, and defending systems 
.
From navigation & file ops 
(ls, cd, pwd, cp, mv) to permissions & ownership 
(chmod, chown, umask), Linux gives you total control. For process & system monitoring 
(ps, top, htop, kill, uptime), you can quickly spot what’s happening inside your machine.
Networking 
is at the heart of cybersecurity: commands like ifconfig/ip a 
, ping 
, traceroute 
, netstat/ss 
, and curl/wget help you diagnose and analyze connections. For security researchers 
, tools like tcpdump 
, nmap 
, and wireshark 
provide deep packet insights.
You’ll also need package & service management 
(apt-get, yum, systemctl, journalctl), archiving & compression 
(tar, gzip, zip/unzip), and text processing 
(grep, awk, sed, sort). Combine them with scripting 
(bash, cron, alias) to automate and scale your work.
Disclaimer:
For educational purposes only. Use these commands responsibly in labs or on systems you manage. 
#Linux #CyberSecurity #InfoSec #SysAdmin #BlueTeam #RedTeam #CommandLine #LinuxCommands #SecurityAwareness
Ayer estuve toda la tarde preparando y grabando un solo ejercicio práctico de configuración de firewall dual con nftables... acá algunas actualizaciones recién salidas del horno 
La semana que viene empiezo a editar y ultimar los detalles!! 
NAT (Network Address Translation) maps private IP addresses inside a network to a public IP address so multiple devices can share a single external identity while communicating over the internet
Here is a visual diagram explaining how NAT works 
#network #sysadmin
Find a high-res pdf book with all my #networking related infographics from https://study-notes.org/networking-ebook.html
All certs give the same encryption — the real differences are in identity checks, automation, support, and compliance.
DV with Let’s Encrypt is perfect for most. OV/EV only matter if policy, contracts, or enterprise governance demand it.
Hostvix · Free vs. Paid SSL - What You Need to Know - HostvixIf you’re skimming: all public-trusted SSL/TLS certificates give you the same encryption. What differs is identity vetting, support/tooling, and sometimes a warranty from the certificate authority (CA). Browsers no longer show the old EV “green bar” or company name in the address bar; users just see a lock/tune icon and the domain. Below I’ll walk...
Acabo de grabar la resolución de una práctica de firewall dual con DMZ usando #nftables en GNU/Linux... casi una hora de video configurando reglas y jugando con los equipos!
¿Quieren aprender nftables? ¿Quieren migrar desde iptables? Espero que este curso sea una buena aproximación!
Ya falta poquito para lanzarlo!
Luego publico un short con las novedades!
How to exclude files from a backup with Plakar: with the 1.0.3 release, the tool now supports gitignore file syntax to exclude files from a backup #SysAdmin https://www.plakar.io/docs/main/guides/excluding-files-from-a-backup/
Plakar - Effortless backupExcluding files from a backup
Gonna have to do a bunch of Debian manual installs for #openzfsmastery, so I'm installing on a flash drive that I can move between test hosts. Yes, I have the live CD, but I want a user account with SSH keys and static IP and all that.
Filesystems. Ugh. #sysadmin
Buenas Practicas para Prevenir Ataques Brute-Force Login SSH en Linux #developer #gnu_linux #networking #sysadmin #cli #debian #fail2ban #linux #python #red_hat #ssh #tips_how_to
https://h4ckseed.wordpress.com/2025/09/17/buenas-practicas-para-prevenir-ataques-brute-force-login-ssh-en-linux/
h4ckseed · Buenas Practicas para Prevenir Ataques Brute-Force Login SSH en LinuxLos servidores que ejecutan SSH suelen ser un blanco fácil para ataques de fuerza bruta. Los ciberatacantes, ciberdelincuentes, entre otros, constantemente desarrollan herramientas innovadoras, ade…
On #OpenZFS:
$ zpool get feature@longname
NAME PROPERTY VALUE SOURCE
usb-pool feature@longname enabled local
$ touch $(python -c 'print("a"*256)')
touch: cannot touch 'aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa': File name too long
Nueva Entrada en #h4ckseed : Buenas Practicas para Prevenir Ataques Brute-Force Login SSH en Linux
Los servidores que ejecutan #SSH suelen ser un blanco fácil para ataques de fuerza bruta. Los ciberatacantes, ciberdelincuentes, entre otros, constantemente desarrollan herramientas innovadoras, ademas de bots para automatizar ataques de fuerza bruta (incluyendo IA, hoy por hoy), lo que aumenta aún más el riesgo de intrusión....
h4ckseed · Buenas Practicas para Prevenir Ataques Brute-Force Login SSH en LinuxLos servidores que ejecutan SSH suelen ser un blanco fácil para ataques de fuerza bruta. Los ciberatacantes, ciberdelincuentes, entre otros, constantemente desarrollan herramientas innovadoras, ade…
Ready to launch your #IT career?
#UpgradetoLinux and share a photo of your new #Linux setup with the hashtags #LPI25 and #switchtolinux to receive a 25% discount on an #LPI #LinuxEssentials exam!
Become part of a #FOSS future and enjoy the rewards: https://lpi.org/pgze
#TZAG gente del #fediverso! Tengan excelente miércoles!
Recuerden que tengo una pregunta de examen activa en las polls, por si quieren pasarse, el viernes damos el feedback! 
MastodonDiego Córdoba 🇦🇷 (@d1cor@mstdn.io)#TZAG #fediverso! 👋
¿Están listos para una pregunta de examen? 🤓 📚
¡Vamos con la poll de esta semana! 💪 👇
❓ ¿Cuál de las siguientes herramientas es la sucesora oficial de iptables en GNU/Linux para la gestión de firewall?
¿Se animan?
Si han estado leyendo algo del blog de #juncotic, ya sabrán la respuesta 😜
Los leo! 💬
#gnu #linux #learning #juncotic #educacion #softwarelibre #opensource #freesoftware #sysadmin #devops #firewall #ciberseguridad #cybersecurity
[ ] ufw
[ ] firewalld
[ ] nftables
[ ] ipchains
Security Alert: Andreas from Anagogistis discovered PureVPN’s Linux clients leak IPv6 traffic & wipe firewall rules without restoring them. Hosting pros relying on “always-on” protection? Think twice.
Use with caution.
anagogistis · PureVPN IPv6 leak | AnagogistisMy personal blog
This is really beautiful, as in art, Things of Beauty. A webserver running on a disposable vape (which for some sick performance of runaway late-stage capitalism runs a whole shiny ARM Cortex board).
https://bogdanthegeek.github.io/blog/projects/vapeserver/
The site it serves was not up for me at the time of GET. Too late I'm a believer.
(... and they're using my #1 fave network tool of tools `socat`)
#linux #sysadmin #selfhosted
BogdanTheGeek's Blog · Hosting a WebSite on a Disposable VapeSomeone's trash is another person's web server.
"Networking for System Administrators, 2nd ed" is now live on Kickstarter! It broke $10k, which means all backers also get a bonus ebook on ZFS. #sysadmin
Replied in thread
@strypey It’s a great set of tips for any consistent habit you need to build.
Had to smile tho - as a #sysadmin I had several known virus signatures or triggers in .txt files ready to test AV updates - usually just one character off triggering or zipped so they wouldn’t trigger without prior warning:
“the humble .txt file can be read by practically every application on your computer, can be pasted directly into an email, and can't transmit a virus” 
The new edition of "Networking for System Administrators" went live on #Kickstarter today.
Next stretch goal: everyone gets a bonus #ZFS book. #n4sa2e #sysadmin