Redhat Certified System Administrator (RHCSA)

These are notes taken while viewing Von Vugt’s videos for RHCSA certification.

Chapter 6: Users and Groups

Useful commands

To add a new user and switch to it

> useradd <username>
> su - <username>

/etc/group lists the group and members. This file can be modified directly, or these commands can be used:

> groupadd <groupadd>
> usermode -aG account <username>

Chapter 12: Virtualization

Prerequisites

Virtualization requires CPU support. To verify a CPU is supported:

> egrep 'vmx | svm' /proc/cpuinfo

To check that the KVM module is installed:

> lsmode | grep kvm

To see if the virtual bridge has been set up for the VMs to share the NIC:

> ip link show

Note that the virtual bridge has an address because it is operating in NAT mode:

> ip addr show

Commands

Here are a few useful commands:

> virsh list # -all
> virsh start small
> virsh destroy small  # despite its name, it only stops the VM

The directory /etc/libvirt/qemu has an XML file with parameters for the VM.

> virsh edit