Specifications

Updates for the Basic Administration Guide

Update–6 VMware, Inc.

Updates to the Linux Requirements for Guest

Customization Section on Page 218

TheLinuxRequirementsforGuestCustomizationsectionshouldincludethefollowing

requirement:

 PerlisinstalledintheLinuxguestoperatingsystem.

Updates to Understanding Snapshots Section on

Page 250

ThesectionUnderstandingSnapshotsdoesnotincludeinformationondeltadisks.The

sectionshouldcontainthefollowingcontent:

Totakeasnapshot,thestateofthevirtualdiskatthetimeoftakingthesnapshotmust

bepreserved.Whenthisoccurs,theguestoperatingsystemcannotwritetotheVMDK

file.

ThedeltadiskisanadditionalVMDKfilewheretheguestisgivenwriteaccess.

Thedeltadiskrepresentsthedifferencebetweenthecurrentstateofthevirtualdiskand

thestateatthetimeoftheprevioussnapshot.Ifmorethanonesnapshotsexist,delta

disksmightrepresentthedifference

(ordelta)betweeneachsnapshot.Also,theguest

canwritetoeverysingleblockofthevirtualdiskcausingthedeltadisktogrowaslarge

asthebaseVMDKofthevirtualmachine.

Whenasnapshotisdeleted,ifauserchoosestomergethechangesbetweenthe

snapshotsto

thepreviousdisk‐state,allthedatafromthedeltadiskthatcontainsthe

informationaboutthedeletedsnapshotiswrittentotheparentdisk.Thismightinvolve

alargeamountofdiskI/Oandmightreducethevirtualmachineperformanceuntil

consolidationiscomplete.

Iftheuserchoosesto

ignorethedeltadisks,deltaconsolidationisnotrequired.

SeeVMwareKnowledgeBasesystemformoreinformationontheiterativesnapshot

deletionbehavior.SeealsoDeleteAllsnapshotoperationresultsinaConsolidate

Helpersnapshotwhenadatastorehasinsufficientdiskspace(KBarticle1003302).

OTEToconsolidateallsnapshotsintothebasevirtualmachine,youmightneedextra

diskspace,aslargeasthebaseVMDK.

OTEWhilesnapshotsprovideapoint‐in‐timeimageofthediskthatbackupsolutions

canuse,snapshotsshouldnotbeusedforvirtualmachinebackups.