Configuring CentOS 7 For RHCSA7 Or RHCE7 Practice Labs

This blog post show you how to correctly configure your CentOS 7 repos so as to obtain only the updated packages for a particular specific version of CentOS 7, thereby avoiding being updated to the latest version of CentOS 7 when updating your system using yum update.

Configure a Local ISO-based Package Repository on a CentOS 7.2 VM

This post shows you how to configure a local ISO-based repository on a CentOS 7.2 VM using CentOS-7-x86_64-Everything-1511.iso

Repair Damaged RPM Database

If you encounter any of the following messages: rpmdb: PANIC: fatal region error detected; run recovery error: db3 error(22) from dbenv->open: Invalid argument error: cannot open Packages index using db3 – Invalid argument (22) error: cannot open Packages database in /var/lib/rpm error: rpmdb: damaged header #1439 retrieved — skipping. or a similar RPM-related error message, it is probable that your RPM database is damaged. RPM uses a database to maintain the package dependency information. This database is normally located at /var/lib/rpm. # cd /var/lib/rpm # ls -al total 86420 drwxr-xr-x. 2 root root 4096 Nov 18 21:09 . drwxr-xr-x. 45

YUM Package Installation Updating and Removal Forensics

In this post, I explore how to use the YUM history database to trace the timeline (installation, updates and removal) of RPM packages on modern RPM-based Linux distributions.

Exploring PackageKit's GNOME Software

This post explores the underbelly of the new GNOME Software application installer and updater tool.