After you have installed the virtualization packages on the host system you can create guest operating systems. This chapter describes the general processes for installing guest operating systems on virtual machines. You can create guest virtual machines using the virt-manager or use the command line interface
virt-install. Both methods are covered by this chapter.
Detailed installation instructions are available in the following chapters for specific versions of Red Hat Enterprise Linux and Microsoft Windows.
6.1. Guest Virtual Machine Prerequisites and Considerations
Various factors should be considered before creating any guest virtual machines. Not only should the role of a virtual machine be considered before deployment, but regular ongoing monitoring and assessment based on variable factors (load, amount of clients) should be performed. Some factors include:
Guest virtual machines should be deployed and configured based on their intended tasks. Some guest systems (for instance, guests running a database server) may require special performance considerations. Guests may require more assigned CPUs or memory based on their role and projected system load.
- Input/Output requirements and types of Input/Output
Some guest virtual machines may have a particularly high I/O requirement or may require further considerations or projections based on the type of I/O (for instance, typical disk block size access, or the amount of clients).
Some guest virtual machines may require higher priority access to storage or faster disk types, or may require exclusive access to areas of storage. The amount of storage used by guests should also be regularly monitored and taken into account when deploying and maintaining storage.
- Networking and network infrastructure
Depending upon your environment, some guest virtual machines could require faster network links than other guests. Bandwidth or latency are often factors when deploying and maintaining guests, especially as requirements or load changes.
- Request requirements
SCSI requests can only be issued to guest virtual machines on virtio drives if the virtio drives are backed by whole disks, and the disk device parameter is set to
lun, as shown in the following example:
<disk type='block' device='lun'>