Virtualization

What this chapter covers

Virtualization is 4% of the Huawei HCIA-Cloud Computing H13-511 exam. It covers what virtualization is, its key terms and features, the two hypervisor types, how CPU, memory and I/O are virtualized, and the mainstream open source technologies Xen and KVM.

Questions are single-answer, multiple-answer without a stated count, true/false, drag and drop and typed fill-in-the-blank, often "Which of the following statements is true?". This exam has no exhibit figures, so every question is plain text.

It has 2 outline topics, and one page covers them.

How the topics fit together

Virtualization lets one physical host run many isolated VMs. The general concepts explain how a hypervisor shares the CPU, memory and devices, and the mainstream technologies show two real ways of building one.

The next chapters apply this to Huawei FusionCompute, whose CNA hosts run KVM based virtualization. Concepts such as virtio drivers and hardware assistance appear there again.

How to use these pages

Each topic page has the same shape, so you can skim for what you need.

• What it is: the idea in plain words.
• How it works: the mechanism, with tables and examples.
• What to remember for the exam: the facts to memorize.
• Common mistakes: the classic traps.
• Check yourself: three questions to test your understanding.

For each technology you meet, say which layer it virtualizes and whether the guest OS must change. The exam often contrasts two approaches in one question.