Installation guide

Chapter 1. Introduction

Emulated sound devices

Two emulated sound devices are available:

• The ac97 device emulates an Intel 82801AA AC97 Audio compatible sound card.

• The es1370 device emulates an ENSONIQ AudioPCI ES1370 sound card.

Emulated network drivers

There are four emulated network drivers available for network devices:

• The e1000 driver emulates an Intel E1000 network adaptor (Intel 82540EM, 82573L, 82544GC).

• The ne2k_pci driver emulates a Novell NE2000 network adaptor.

• The pcnet driver emulates an AMD Lance Am7990 network adaptor.

• The rtl8139 driver emulates a Realtek 8139 network adaptor.

Emulated storage drivers

Storage devices and storage pools can use the emulated drivers to attach storage devices to

virtualized guests. Alternatively, the para-virtualized drivers can be used.

Note that the storage drivers are not storage devices. The drivers are used to attach a backing storage

device, file or storage pool volume to a virtualized guest. The backing storage device can be any

supported type of storage device, file, or storage pool volume.

The emulated IDE driver

The KVM hypervisor provides two emulated PCI IDE interfaces. The emulated IDE driver can be

used to attach any combination of up to four virtualized IDE hard disks or virtualized IDE CD-ROM

drives to each virtualized guest. The emulated IDE driver is used for virtualized CD-ROM and

DVD-ROM drives.

The emulated floppy disk drive driver

The emulated floppy disk drive driver is used for creating virtualized floppy drives.

1.4.2. Para-virtualized drivers

Para-virtualized drivers are device drivers that increase the I/O performance of virtualized guests.

Para-virtualized drivers decrease I/O latency and increase I/O throughput to near bare-metal levels.

It is recommended to use the para-virtualized drivers for virtualized guests running I/O intensive

applications.

The para-virtualized drivers must be installed on the guest operating system. By default, the para-

virtualized drivers are included in Red Hat Enterprise Linux 4.7 and newer, Red Hat Enterprise Linux

5.4 and newer and Red Hat Enterprise Linux 6.0 and newer. The para-virtualized drivers must be

manually installed on Windows guests. For more information on using the para-virtualized drivers refer

to Chapter 11, KVM Para-virtualized Drivers.

Para-virtualized network driver

The para-virtualized network driver is a Red Hat branded virtual network device. The para-virtualized

network driver can be used as the driver for existing network devices or new network devices for

virtualized guests.