Build a Linux Bridge Safely With Ip or NetworkManager
Put the host’s IP, routes, and DNS in the right place with this guide to temporary iproute2 bridges, persistent NetworkManager profiles, and safe checks.
Tag: Linux system administration
WireGuard Linux Server Setup: A Reliable Step-by-Step
Set up WireGuard on a Linux server with clear steps for keys, routing, firewall rules, NAT, split tunnels, handshakes, and full-tunnel DNS safely.
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.
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.
Rmdir vs Rm: Safe Linux Deletion Without Guesswork
The safer choice depends on what you are deleting: compare rmdir, rm, rm -r, and rm -rf, plus checks to avoid accidental Linux data loss before you delete.
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.
A Practical Linux Log-Checking Workflow That Works
Start with the current boot, then narrow failures by service, time, kernel, app, or container using journalctl, dmesg, and /var/log without drowning in noise.
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.
Optimize a Web Server on Linux VPS: Measure First
Find the real bottleneck before touching sysctl, swap or BBR. Measure CPU, memory, disk and network on your VPS, then tune only what the numbers point at.
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.
Linux VPS Setup: KVM Over OpenVZ for Real Control
KVM-virtualized Linux VPS with 2GB RAM gives you root access and debugging power. Learn sizing, security hardening, and why container plans fall short.
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.
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.
Network Segmentation in a Homelab: 6 Setup Steps
A secure homelab starts with untrusted devices on their own VLAN; this guide covers trunks, access ports, firewall rules, Wi-Fi, and testing.
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.
Ubuntu Kernel Rollback: Boot the Safe GRUB Entry
Boot an older Ubuntu kernel safely through GRUB, verify the cause, preserve a fallback, and remove or set defaults only after the system is stable.
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.
Why Apt Says Bpftool Is a Virtual Package (and the Fix)
Two packages, not one: linux-tools-common plus linux-tools-$(uname -r) gets bpftool working on Ubuntu, with checks for virtual package and pocket errors.