How to Load HPC Modules and Verify Your Shell
Use explicit module versions and verify PATH changes with module list and which, while this guide explains hidden modules, conflicts, batch jobs, and modprobe.
Tag: Linux system administration
How to Run Memtest86 for Reliable RAM Diagnostics
Bare-metal memory testing with MemTest86 catches faults that in-OS tools miss. Learn why multiple passes matter and how to read failing addresses.
Safe Linux Directory Removal: Rmdir vs Rm -R
Use rmdir first to verify empty directories, then rm -r for deletions. Learn when rm -rf is justified and how to avoid catastrophic mistakes.
Fix Broken Dependencies in Dnf: Read the Error First
Broken dnf dependencies usually stem from stale cache or mismatched repos, not missing packages. Learn to trace the actual problem with repoquery and logs.
Fix Permission Denied in Linux: Diagnose Before Chmod
Permission denied errors stem from specific syscall failures. Learn to read ls output, use chmod and chown correctly, and diagnose issues chmod can’t fix.
How Linux File Descriptors Work: The Three-Layer Model
File descriptors are per-process integers that index into a three-layer table structure. Learn how the kernel connects descriptors to open files and inodes.
Nginx as Linux Reverse Proxy: Setup and Alternatives
nginx leads for Linux reverse proxies with event-driven workers. Learn setup steps, when to choose HAProxy or Caddy, and security best practices.
Pick a Linux Control Panel by Server Size, Not Hype
Match your panel to your workload: CloudPanel for single servers, cPanel for resellers, DirectAdmin for lean alternatives. Compare free and paid options.
Five Controls for Secure Linux App Deployment
Master the five load-bearing controls that stop most attacks: non-root user, key-only SSH, default-deny firewall, reverse proxy, and scheduled patching.
Automatic Kernel Module Blacklisting for Sysadmins
Sysadmins automating kernel module blacklisting must verify each module’s purpose before fleet deployment to avoid silent boot failures and outages.
Lsmod vs Modprobe: List Loaded Kernel Modules
lsmod lists what the kernel loaded right now; modprobe loads modules and resolves dependencies. Learn which tool does what and why modprobe list doesn’t exist.
Remove Old Kernels on Rocky Linux: Dnf Method
Set installonly_limit=3 in dnf.conf, run dnf remove –oldinstallonly, then grub2-mkconfig to free /boot space and prevent kernel pile-up on Rocky Linux.
Ubuntu Modules-Load.d: Autoload Kernel Modules at Boot
Use /etc/modules-load.d/.conf files with systemd-modules-load.service to persistently autoload kernel modules on Ubuntu. Step-by-step setup and troubleshooting.
VLAN Tagging for Homelabs: 802.1Q Setup Guide
Segment your homelab network with VLAN tagging using 802.1Q. Learn switch configuration, trunk setup, and firewall rules to isolate IoT and untrusted devices.
A Clean OpenWrt VM Design for Proxmox VLANs
Separate firmware, virtual hardware, and VLAN decisions to build a reliable OpenWrt router VM on Proxmox, with OVMF, virtio NICs, bridges, and trunks.
Automatic Linux Kernel Upgrades: Setup Guide
Set up automatic Linux kernel upgrades safely with unattended-upgrades or live patching. Learn when to automate, how to verify updates, and rollback strategies.
Fix Apt Install Bpftool Virtual Package on Ubuntu Noble
bpftool is a virtual package on Ubuntu Noble – install linux-tools-common plus linux-tools-$(uname -r) to get a working binary matched to your kernel.