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

In a recent blog post, I demonstrated how to set up a local RPM repository (repo) in a VMware CentOS 7.2 VM (AKA guest) running under VMware Workstation (AKA the host.) This made the CentOS VM independent of the need for network access w.r.t. RPM package installation. However, the trade off for the ability to install packages without Internet access is the 6 GB plus increase in the size of the VM necessitated for storing all the packages and metadata. Consider the following alternative scenario. You have downloaded the CentOS-7-x86_64-Everything-1511.iso from the CentOS Project or a mirror, used the ISO

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

Consider the following scenario. You have downloaded the CentOS-7-x86_64-Everything-1511.iso from the CentOS Project or a mirror, used the ISO to create a VM in VMware Workstation, and now want to be able to access a package repository (repo) when you have no Internet access. Assume that a GNOME desktop is available on your CentOS VM and the VM is sized such that you have at least 8 Gb of free disk space. Copy the IS0 to your CentOS VM by whatever method works for you. If you have VMware Tools installed, you can just drag and drop the file using

RHCSA Preparation - Script to Configure a Simple OpenLDAP Server

The ability to quickly configure an LDAP (Lightweight Directory Access Protocol) client for accessing user and group accounts is one of the skills you are expected to have when you sit the Red Hat RHSCA exam. LDAP is a application-level protocol for accessing and maintaining distributed directory services over an IP-based network. It is specified in a series of RFCs (Request for Comments) using ASN.1. The latest LDAP specification is Version 3, published as RFC 4511. Typically, at a minimum, LDAP is used to facilitate centralized user and group account administration. Instead of storing user and group account information locally

Nesting RHEL7 KVM on VMware Workstation 12

Recently I wished to build a Red Hat Enterprise Linux 7 (RHEL7) appliance with 2 KVM-virtualized guests. Essentially a type 2 hypervisor (VMM) on top of another type 2 hypervisor. I installed RHEL7 on VMware Workstation 12 and configured it as a Virtualization Server. It was a smooth install without any issues. However I was surprised to find that KVM (Kernel-based Virtual Machine) simply did not work at all and lsmod did not even list the KVM kernel modules. It turns out that you need to do two changes to your RHEL7 guest configuration file in order for KVM support

Fastest Way to Gain Root Access in RHCSA7 Exam

Time is at a premium during the RHCSA exam. Every minute you can save on a task is a minute as it can be applied to some other task. If you have to reboot the operating system, that is wasting time as you cannot be doing anything useful in terms of task completion during the reboot. One critical task is to require you to gain root access to the installed and running operating system. This is typically the first thing you need to do in the exam. There are many blogs and write-ups on how to do this by modifying