Specifications

VMware, Inc. 29

Chapter 1 Introduction to VMware ESX Server

Figure 1-3. virtual Machine configuration

In!Figure 1‐3,!each!virtual!machine!is!configured!with!one!CPU,!an!allocation!of!

memory!and!disk,!and!two!virtual!Ethernet!adapters.!In!reality,!they!share!the!same!

physical!CPU!and!access!noncontiguous!pages!of!memory!(with!part!of!the!memory!of!

one!of!the!virtual!machines!currently!swapped!

to!disk).!Their!virtual!disks!are!set!up!as!

files!on!a!common!file!system.

Each!of!the!example!virtual!machines!has!two!virtual!NICs.!Virtual!NICs!1a!and!2a!are!

attached!to!the!virtual!switch!that!is!bound!to!physical!NICs!1a!and!2a.!Virtual!NICs!1b!

and!2b!are!

attached!to!a!purely!virtual!switch.

Software Compatibility

In!the!VMware!ESX!Server!architecture,!guest!operating!systems!interact!only!with!the!

standard!x86‐compatible!virtual!hardware!presented!by!the!virtualization!layer.!This!

provides!the!capability!for!VMware!to!support!any!x86‐compatible!operating!system.

In!practice,!VMware!supports!a!subset!of!x86‐compatible!operating!systems!that!are!

tested!throughout!

the!product!development!cycle.!VMware!documents!the!installation!

and!operation!of!these!guest!operating!systems!and!trains!its!technical!personnel!in!

their!support.!

Because!applications!interact!only!with!their!guest!operating!system,!and!not!with!the!

underlying!virtual!hardware,!after!operating!system!compatibility!with!the!virtual!

hardware!is!established,!application!compatibility

!is!not!an!issue.

Virtual machine 1

Virtual machine 2

Memory

Disk

Physical resources

NIC

Virtual network

Memory Memory

Disk

NIC

CPU

CPU1

Mem1

Disk1

NIC1a

NIC1b

CPU2

Mem2

Disk2

NIC2a

NIC2b