6.1.1 About Oracle Linux KVM

Oracle Linux KVM enables you to deploy the Oracle Linux operating system and application software within a supported virtual environment that is managed by KVM.

Starting with Oracle Exadata System Software release 19.3.0, KVM is the virtualization technology used with Oracle Exadata systems configured with RDMA over Converged Ethernet (RoCE) interconnects. An Oracle Linux KVM environment consists of a management server (the KVM host), virtual machines, and resources. A KVM host is a managed virtual environment providing a lightweight, secure, server platform which runs multiple virtual machines (VMs), also known as guests.

The KVM host is installed on a bare metal computer. The hypervisor on each KVM host is an extremely small-footprint VM manager and scheduler. It is designed so that it is the only fully privileged entity in the system. It controls only the most basic resources of the system, including CPU and memory usage, privilege checks, and hardware interrupts.

The hypervisor securely runs multiple VMs on one host computer. Each VM runs in its own guest and has its own operating system. The KVM host has privileged access to the hardware and device drivers and is the environment from where you manage all the guests.

A guest is an unprivileged VM that uses a defined set of system resources. The guest is started and managed on the KVM host. Because a guest operates independently of other VMs, a configuration change applied to the virtual resources of a guest does not affect any other guests. A failure of the guest does not impact any other guests.

In general, each KVM host supports up to 12 guests. However, the limit is 8 guests on servers that contain 384 GB of RAM and are configured to support Exadata Secure RDMA Fabric Isolation.

Each guest is started alongside the KVM host. The guests never interact with the KVM host directly. Their requirements are handled by the hypervisor. The KVM host only provides a means to administer the hypervisor.

Oracle Exadata Deployment Assistant (OEDA) provides facilities to configure Oracle Linux KVM on Oracle Exadata. You can also use the vm_maker command-line utility to administer Oracle Linux KVM guests.

Note:

Exadata does not support direct manipulation of KVM guests by using the virsh command.