Virtualization technology was created to allow for efficient use of physical computing resources in IT Infrastructures. Each Virtual Machine will have its file system, network interface, IP address and other peripherals attached to it. The hypervisor is the software component on the host that manages and supports the physical server virtualization.
The work of the hypervisor is to run virtual machines for each virtualized operating system by providing access to virtual memory, storage, networking, CPUs, GPUs, and other system peripherals. It ensures there is restriction of virtual machines from having direct access to hardware or other virtual machines. In Virtualization, a host is the physical machine and operating system providing the hypervisor.
What is oVirt?
oVirt is an open source virtualization platform that provides centralized management of virtual servers, hosts, and desktops across one or more enterprise data centers. oVirt is based on Linux OS, Kernel-based Virtual Machine (KVM) technology, and other software components that delivers the entire Virtualization platform.
oVirt offers great features that suit enterprise-grade virtualization.
- Live migration of Virtual Machines
- Virtual Machines high availability, feature extension of Live migration
- System scheduling
- Power management
- Image management
- Monitoring through Grafana dashboards
- Snapshots management for your Virtual Machines
- Thin provisioning of VMs
- Among other features
Below are the key components of oVirt virtualization platform.
Service that provides a graphical user interface and a REST API to manage the resources in the environment. The Engine is installed on a physical or virtual machine running Enterprise Linux.
Enterprise Linux hosts (Enterprise Linux hosts) and oVirt Nodes (image-based hypervisors) are the two supported types of host. Hosts use Kernel-based Virtual Machine (KVM) technology and provide resources used to run virtual machines.
A storage service is used to store the data associated with virtual machines.
A service that collects configuration information and statistical data from the Engine.
This article will be focused on the installation of oVirt hypervisor components on Rocky Linux 8 / AlmaLinux 8 server. For oVirt Engine setup refer to our guide in the following link:
The requirements on the server to be used as oVirt compute host must meet the following;
- CPU Requirements: The CPUs on the hosts system must have support for the Intel® 64 or AMD64 CPU extensions, and the AMD-V™ or Intel VT® hardware virtualization extensions enabled.
- Memory Requirements: The minimum of memory required in a host is 2 GB, and supports up to 4 TB of RAM per Virtual Machine deployed on oVirt Node
- Storage Requirements: Storage can be local or network-based. The total minimum storage requirement on the node is 55 GiB
- Networking requirements: oVirt requires IPv6 to remain enabled on the physical or virtual machine running the Engine
- Network Interface: 1 Network Interface Card (NIC) with bandwidth of at least 1 Gbps.
- DNS(hostnames) and NTP time synchronization configured
Virtual Desktop Server Manager (VDSM) management agent
On every oVirt host (hypervisor) is the Virtual Desktop Server Manager (VDSM) management agent that runs to allow for communication between the oVirt Manager (Engine) and compute hosts. This VDSM allows oVirt Manager to manage virtual machines and storage, and retrieve statistics from hosts and guests. it uses libvirt to perform basic virtual machine life-cycle commands, such as start, stop, and reboot.
Step 1 – Configure hostname, DNS and NTP
We need a good DNS name configured on our server. My first oVirt node will have the hostname set below:
Hostname="ovirt-node-01.hirebestengineers.com" sudo hostnamectl set-hostname $Hostname
Update DNS server and add A record for the name we’ve used on the server. You can also use
/etc/hosts file if no DNS server in your infra.
[[email protected] ~]# ip ad show 1: lo:
mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: enp1s0: mtu 1500 qdisc fq_codel state UP group default qlen 1000 link/ether 52:54:00:36:ad:26 brd ff:ff:ff:ff:ff:ff inet 192.168.70.3/24 brd 192.168.70.255 scope global noprefixroute enp1s0 valid_lft forever preferred_lft forever inet6 fe80::5054:ff:fe36:ad26/64 scope link valid_lft forever preferred_lft forever [[email protected] ~]# vi /etc/hosts # oVirt Nodes 192.168.70.2 ovirt-manager.hirebestengineers.com ovirt-manager 192.168.70.3 ovirt-node-01.hirebestengineers.com ovirt-node-01
Also set correct timezone of your region:
sudo timedatectl set-timezone Africa/Nairobi
Install chrony ntp server package
sudo yum -y install chrony
Start the service and sync date on the server
sudo systemctl enable --now chronyd sudo chronyc sources
Verify current date setting on the server
[[email protected] ~]# date Tue Jan 11 00:17:39 EAT 2022
Step 2 – Add oVirt RPM Repository to Rocky Linux 8 / AlmaLinux 8
There is an official YUM repository for EL systems that we can add and install required packages from it. An alternative installation is from oVirt host ISO file.
We can run the command shared to enable oVirt repos on our system
sudo yum -y install https://resources.ovirt.org/pub/yum-repo/ovirt-release44.rpm
List all repositories available after addition
[[email protected] ~]# yum repolist repo id repo name appstream Rocky Linux 8 - AppStream baseos Rocky Linux 8 - BaseOS extras Rocky Linux 8 - Extras ovirt-4.4 Latest oVirt 4.4 Release ovirt-4.4-advanced-virtualization Advanced Virtualization packages for x86_64 ovirt-4.4-centos-ceph-pacific Ceph packages for x86_64 ovirt-4.4-centos-gluster8 CentOS-8 - Gluster 8 ovirt-4.4-centos-nfv-openvswitch CentOS-8 - NFV OpenvSwitch ovirt-4.4-centos-opstools CentOS-8 - OpsTools - collectd ovirt-4.4-centos-ovirt44 CentOS-8 - oVirt 4.4 ovirt-4.4-copr:copr.fedorainfracloud.org:sac:gluster-ansible Copr repo for gluster-ansible owned by sac ovirt-4.4-copr:copr.fedorainfracloud.org:sbonazzo:EL8_collection Copr repo for EL8_collection owned by sbonazzo ovirt-4.4-epel Extra Packages for Enterprise Linux 8 - x86_64 ovirt-4.4-openstack-victoria OpenStack Victoria Repository ovirt-4.4-virtio-win-latest virtio-win builds roughly matching what will be shipped in upcoming RHEL
We can confirm there are oVirt repositories enabled on the system. We’ll be using them to install the packages needed to turn our Rocky Linux 8 / AlmaLinux 8 system into oVirt Virtualization compute node.
Step 3 – Install oVirt Packages and dependencies
Install the oVirt Cockpit module and other packages required:
sudo dnf -y install cockpit cockpit-ovirt-dashboard
If the node will be used to configure Glusterfs or deploy oVirt Manager as hosted engine, install these extra packages:
sudo dnf install gluster-ansible-roles ovirt-engine-appliance
Then enable and start cockpit socket
sudo systemctl enable cockpit.socket sudo systemctl start cockpit.socket
If firewalld service is active, allow cockpit service on the firewall using
sudo firewall-cmd --add-service=cockpit sudo firewall-cmd --add-service=cockpit --permanent sudo firewall-cmd --reload
Step 4 – Prepare Storage for oVirt use
We have an article on configuring NFS storage for oVirt.
The only steps necessary for this setup are Step 1 and Step 2. Other steps can only be performed after addition of Compute host/hypervisor.
Step 5 – Add Compute host from oVirt managent portal
Ensure server names for oVirt Engine and your compute hosts are set correctly. Forward and reverse lookup records must both be set in the DNS. You can update
/etc/hosts file with correct names and IP addresses.
# Updating /etc/hosts file 192.168.70.2 ovirt-manager.hirebestengineers.com ovirt-manager 192.168.70.3 ovirt-node-01.hirebestengineers.com ovirt-node-01
Login to oVirt Manager administration portal using set username and password.
Navigate to Compute > Hosts > New
Select the Data Center for Host Cluster in the drop-down list for the new host. Then fill all required information for the host to be added – Name, IP address, and authentication details.
For SSH Public Key authentication, you’ll copy the key displayed in the SSH Public Key field to
/root/.ssh/authorized_keys on the host.
[[email protected] ~]# vi /root/.ssh/authorized_keys #Paste-pub-key-here
Ansible is used to automatically configure new host. Click on its name to check progress
Provisioning progress is available inside Events tab.
Once the installation of oVirt host is done. There will be ansible deployment success message in events logs.
Login and reboot the host before you can use it
[[email protected] ~]# reboot
Node status should be in Up status after the reboot.
A logical network called ovirtmgmt is created automatically by the provisioner. This is usable for most workloads unless you have a special requirement for multiple network interfaces.
The host primary interface will be bound to the Linux bridge created:
[[email protected] ~]# cat /etc/sysconfig/network-scripts/ifcfg-enp1s0 NAME=enp1s0 DEVICE=enp1s0 ONBOOT=yes NETBOOT="yes" TYPE=Ethernet MTU=1500 UUID=c0ab6b8c-0eac-a1b4-1c47-efe4b2d1191f LLDP=no BRIDGE=aef0841b-771f-4bd7-a987-0791b97fa3b7 # cat /etc/sysconfig/network-scripts/ifcfg-ovirtmgmt STP=no TYPE=Bridge HWADDR= MTU=1500 PROXY_METHOD=none BROWSER_ONLY=no BOOTPROTO=none IPADDR=192.168.77.3 PREFIX=24 DNS1=22.214.171.124 DNS2=126.96.36.199 DEFROUTE=yes DHCP_CLIENT_ID=mac IPV4_FAILURE_FATAL=no IPV4_DNS_PRIORITY=40 IPV6_DISABLED=yes IPV6INIT=no ROUTING_RULE_1="priority 3200 to 192.168.77.0/24 table 329647082" ROUTING_RULE_2="priority 3200 from 192.168.77.0/24 table 329647082" NAME=ovirtmgmt UUID=aef0841b-771f-4bd7-a987-0791b97fa3b7 DEVICE=ovirtmgmt ONBOOT=yes AUTOCONNECT_SLAVES=yes
More networks can be created from oVirt Management portal as required by your applications and mapped on the hosts. Next you configure storage domains in your oVirt data center. Check out our guide
In addition to this blog post, there are a number of useful resources that helps with the deployment and usage of oVirt Virtualization platform. In particular, visit and review the official oVirt Documentation. Navigate through various sections and access some useful information. Our future guides will demonstrate operations on oVirt environment from the user and Systems Administrator perspective. Stay connected for daily updates!.