How to Install and Configure Red Hat Virtualization Host (RHVH)
Red Hat Virtualization Host (RHVH) is a minimal operating system based on Red Hat Enterprise Linux designed to provide a simple method of setting up a physical machine to act as a hypervisor in a Red Hat Virtualization environment. It initially contains only the packages needed to act as a hypervisor and integrate with Red Hat Virtualization Manager and includes a Cockpit user interface to allow monitoring and management of the host.
Red Hat Virtualization Host and its virtual machine guests are managed by Red Hat Virtualization Manager through a service called the Virtual Desktop and Server Manager (VDSM). Red Hat Virtualization Manager communicates with the vdsmd service on each of its Red Hat Virtualization Hosts to monitor and manage their memory, storage, and networks, and to create, migrate, and destroy virtual machines.
Installing Red Hat Virtualization Host (RHVH)
Red Hat Virtualization Host is provided as an ISO image from Customer Portal (https:// access.redhat.com/). To get the image, log in to Customer Portal and click Red Hat Virtualization. Click Download Latest to access the product download page. Find the Red Hat Virtualization Host image and click Download Now.
Once you have the ISO image, it can be used to create bootable media to install the operating system. If you do not know how to do this, there are instructions available in the “Making Media” chapter of the Red Hat Enterprise Linux 7 Installation Guide at https://access.redhat.com/ documentation/. You can then use the bootable media to start the installation process on the new host.
The installer uses the same software as Red Hat Enterprise Linux, a system called Anaconda. You can install Red Hat Virtualization Host interactively, or you can perform a Kickstart-based automatic installation. This section focuses on the manual installation process.
When the installer starts in manual interactive mode, a graphical interface is activated. The first screen asks What language would you like to use during the installation process?. The default selection is English (United States). Once you have selected your preferred language, click the Continue button.
The next screen displays a number of different configuration options in a “hub-and-spoke” model. You can select these options in any order to configure different aspects of the installation, and you can revisit them if you change your mind about a setting prior to starting the installation.
– DATE & TIME configures the clock. You can set the timezone for the host using a graphical map or by selecting it by Region and City. UTC (Coordinated Universal Time) is available from the Etc region.
– KEYBOARD is used to configure the physical keyboard type attached to the host.
– INSTALLATION DESTINATION specifies how to format and partition the local disk for the Red Hat Virtualization Host. There are two options for this section.
1. Automatically configure partitioning is strongly recommended by Red Hat. This mode automatically determines the optimal storage configuration for the available storage and apply it. /boot is configured with a standard partition, but/and a number of other file systems are created on thinly-provisioned logical volumes.
2. I will configure partitioning allows you to customize the file system sizes and layout on the Red Hat Virtualization Host. However, to use this correctly you need to understand what directories must be on which file systems, which can not be on separate file systems, and what the size requirements are for each of them. In general, it’s simpler and safer to use the automatic settings unless you have some special case that requires manual configuration.
– NETWORK & HOSTNAME configures networking settings. By default, all detected network interfaces are disabled. You need to select the interfaces you want to enable from the list on the left pane and then click the button in the upper right to ON. By default, DHCP is used to configure the network interface. This screen also allows you to manually set the hostname for
You should also click the Configure button to ensure that the interface activates automatically at boot. Click the General tab and ensure that the checkbox for Automatically connect to this network when it is available is selected. Other tabs in the network configuration dialog window allow you to manually configure the IP address, netmask, and other information, create bonded interfaces or perform other advanced configuration tasks.
Note: Make sure that Automatically connect to this network when it is available is selected or the network interface will not come up automatically when the host is rebooted.
– You can also adjust the KDUMP and SECURITY POLICY settings for the Red Hat Virtualization Host, but the system will work fine with the default settings.
Once you click the Begin Installation button, installation begins and a new screen opens displaying a progress bar. That screen also displays two additional configuration items:
- ROOT PASSWORD allows you to set the root password on the host so you can log into it for maintenance.
- USER CREATION allows you to create an additional non-privileged user on the Red Hat Virtualization Host. This is not recommended for security reasons. In general, administration of the Red Hat Virtualization Host will be performed through the Administration Portal on the Red Hat Virtualization Manager.
Once the installation finishes, click Reboot to reboot and start the new Red Hat Virtualization Host. Log into its physical console as root using the password set during installation. When you log in, the node’s current operation status and the URL to its Cockpit administration console is displayed on the terminal.
Red Hat Virtualization Host 4.1 (el7.4) Kernel 3.10.0-693.el7.x86_64 on an x86_64 rhvh login: root Password: node status: OK See `nodectl check` for more information Admin Console: https://172.25.250.10:9090 [[email protected] ~]#
Adding a RedHat Virtualization host to RHV
Once the Red Hat Virtualization Host has been installed, it needs to be added to the Red Hat Virtualization environment. Assign the Red Hat Virtualization Host to a particular data center. This determines the set of virtual machines, storage resources, and network resources available to the host. Hosts in a data center are also organized into clusters. A cluster is a set of hosts that share the same storage and networking infrastructure and act as a migration domain within which virtual machines can be moved from host to host. Hosts in the same cluster generally should be standardized to use the same make, model, hardware, and firmware or BIOS version to provide consistent performance from host to host.
Use the Administration Portal on your Red Hat Virtualization Manager to add and configure your new Red Hat Virtualization Host as part of the environment.
Follow these steps to manually add a new Red Hat Virtualization Host to the environment using Administration Portal:
1. Log in to the Administration Portal as user admin with the correct password and the authentication domain set to internal.
2. Navigate to the Hosts tab.
3. Click the New button to bring up the New Host dialog.
A number of configuration settings need to be filled in on this form in order to add the new Red Hat Virtualization Host to the environment:
By default, Red Hat Virtualization Manager automatically updates the firewall rules on the Red Hat Virtualization Host being added to allow any network connections that are needed. Under Advanced Parameters, this can be disabled by unselecting Automatically configure host firewall. Normally, you do not want to do this unless you are manually managing the host’s firewall through some other means.
4. Click the OK button to configure the host. Red Hat Virtualization Manager connects to the host over SSH and makes any configurations changes that are needed. If errors are reported, you can use Administration Portal to remove the host from the environment, fix the problem reported, and try again.
5. Navigate to the Hosts tab in the Administration Portal and wait for the new host to appear. It should initially appear with a status of Installing, but it should move through Non Responsive to Up after a moment.
Managing RedHat Virtualization Host
Red Hat Virtualization Host 4 includes a new web administration interface based on Cockpit. This interface allows remote administration or inspection of individual hosts from a web browser.
Officially, direct administration of Red Hat Virtualization Host through manual SSH connections is not supported, but administration through the Cockpit interface is. The interface can display a variety of information including the host’s health status, self-hosted engine status, virtual machines, and virtual machine statistics.
Some other administrative operations that can be performed through Cockpit on a Red Hat Virtualization Host include:
- Display a list of the virtual machines running on the host.
- Display a list of the virtual machines in the host’s cluster.
- Comprehensive statistics for running virtual machines.
- Providing console access to running virtual machines.
- Starting virtual machines.
- Shutting down or forcing power off for virtual machines.
- Editing the vdsm.conf file.
- Management of the vdsmd service.
- Deployment of a self-hosted Red Hat Virtualization Manager.
The Cockpit user interface can be accessed through HTTPS connections to port 9090 on the Red Hat Virtualization Host. The URL for the Cockpit user interface is displayed when you log in to the host’s physical console as root.
Note: Like Red Hat Virtualization Manager’s Administration Portal, the Cockpit service on Red Hat Virtualization Host may offer a TLS certificate for the HTTPS connection that is signed by a Certificate Authority your web browser does not recognize. There are a number of ways to work around this, including adding a security exception for that certificate in your web browser.
To log in to the Cockpit administrative interface, use the root user and password you set when you installed the host.
After manual installation of RHVH, one thing you might use Cockpit to do is to register the host for software updates with the Content Distribution Network. The basic procedure to do this is:
1. Log into the RHVH host as root using Cockpit.
2. Under the host’s tab, on the Subscriptions subtab, click Register System. Use the Customer Portal username and password associated with your host entitlements to register.
3. On the Terminal subtab, at the shell prompt use subscription-manager to enable the rhel-7-server-rhvh-4-rpms repository:
subscription-manager repos --enable=rhel-7-server-rhvh-4-rpms