Categories
SecOps

How to trace packets as they pass through the firewall

Trace packets as they pass through the iptables firewall.

Categories
SysOps

How to create custom bash prompt

Today, I will show you my personal shell prompt, so you could define your own custom bash prompt.

Categories
SysOps

How to execute rc.local shell script during boot using systemd

Execute rc.local shell script during boot using systemd compatibility generator.

Categories
SysOps

How to perform shell script analysis

Perform shell script analysis using shellcheck, a shell script static analysis tool.

Categories
SysOps

How to format and beautify Nginx configuration

Format and beautify Nginx configuration using dedicated utilities like nginx-config-formatter, nginxbeautifier, and crossplane.

Categories
SysOps

How to display bind mounts

The simplest possible solution to display bind mounts.

How to determine when the operating system was booted

I have already described how to accurately determine when the system was booted, but there is a simpler solution as you can use /proc filesystem directly.

How to to fix container which cannot be started

The short story of my experience with container is marked for removal and cannot be started error
which was caused by driver "overlay" failed to remove root filesystem for ...: remove /var/lib/docker/overlay/.../merged: device or resource busy.

How to extract specific file from tar archive

Extract a specific file from a tar archive.

How to increase the system-wide number of available file handles

Increase the system-wide number of available file handles (open files).