Installation guide

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VMware ESX Server Administration Guide
Disk Virtualization
Support of disk devices in ESX Server is an example of the product’s hardware
independence. Each virtual disk is presented as a SCSI drive connected to a SCSI
adapter. This device is the only disk storage controller used by the guest operating
system, despite the wide variety of SCSI, RAID and Fibre Channel adapters that might
actually be used in the system.
This abstraction makes virtual machines at once more robust and more transportable.
There is no need to worry about the variety of potentially destabilizing drivers that
may need to be installed on guest operating systems, and the file that encapsulates a
virtual disk is identical no matter what underlying controller or disk drive is used.
VMware ESX Server can be used effectively with storage area networks (SANs). ESX
Server supports QLogic and Emulex host bus adapters, which allow an ESX Server
computer to be connected to a SAN and to see the disk arrays on the SAN.
Network Virtualization
You may define up to four virtual network cards within each virtual machine. Each
virtual network card has its own MAC address and may have its own IP address (or
multiple addresses) as well. It may be mapped to a dedicated network interface on
the physical server (which is known as a VMnic), or virtual network interfaces from
multiple virtual machines may be connected to a single network card. ESX Server
manages both the allocation of resources and the secure isolation of traffic meant for
different virtual machines even when they are connected to the same physical
network card.
A third choice involves binding a virtual network interface to a VMnet, a private
network segment implemented in memory within the ESX Server system but not
bound to an external network.