Use thisoptiontochangea widevarietyoflogicalvolume characteristics,affecting itssize,physicallocation,andallotherattributes.
Ascreencontaininga listofalllogicalvolumesdefinedonthemediaisdisplayed, suchasthefollowingexample:
+---+
| Select PVs for "adsmlv" Logical Volume | +---+
The followingare physical volumes in the "adsmvg" volume group:
PVname Location Description
hdisk5 04-02-L SSA Logical Disk Drive
==> hdisk6 04-02-L SSA Logical Disk Drive hdisk7 04-02-L SSA Logical Disk Drive
+---+
| Select PVs to addto or remove from "adsmlv" logical volume. |
| The "==>" symbolindicates those currently selected. | +---+
| Use ARROW or Tabkeys to move, ENTER to select or de-select, ESC to cancel. | +---+
Figure11-7.AListofPhysicalVolumesAssignedtotheVolumeGroup
The listof logicalvolumesincludesthecreationpriority,number oflogical partitions (size),minimumrecommendedpartitions,numberofcopies, and filesystem mountpoint(ifany).Ifa logicalvolume hadpreviouslybeenchanged sothat itwould notbe created,thelineincludesthemessage“*WILL NOTBE CREATED*”.
Tochangetheattributesof alogicalvolume,selecta logicalvolume andpress Enter.Ascreensuchasthefollowingisdisplayed,indicatingthecurrentlogical volume attributes:
The boxattheupper-leftportionofthescreencontainsinformationthatmight assistinmaking changestothelogicalvolume size.TheOriginalsizefield
+---+
| Change Logical Volume Attributes |
+---+
LV Name VGName Pri LPs MinLPs Copies MountPoint
hd5 rootvg 03 1 0 1
-loglv02 adsmvg 04 1 0 1
-hd8 rootvg 04 1 0 1
-loglv00 sysbackvg 04 2 0 1
-hd6 rootvg 10 40 0 1
-sblv rootvg 20 3 0 1
-hd4 rootvg 20 4 2 1 /
adsmlv adsmvg 20 200 107 1 /adsmfs
hd1 rootvg 20 2 1 1 /home
lv03 sysbackvg 20 52 48 1 /home/sysback
lv00 sysbackvg 20 50 48 1 /home/sysback/build
lv04 sysbackvg 20 21 14 1 /netscape
MORE..5 +---+
| Select a logical volumefrom the above list. |
| |
+---+
| Use ARROW or Tab keysto move and ENTER to select. Press ESC to cancel. | +---+
Figure11-8.AListofAllLogicalVolumesDefinedontheMedia
+---+
| Change"adsmlv" Logical Volume Attributes | +---+
Create this LV? * yes Inter-policy m (minimum)
Logical Volume name adsmlv Stripe size 0
Volume Group name* adsmvg Use PP map? no
Size (in LPs) * 200 MWC? yes
Copies * 1 Write verify? no
Priority 20 Bad block relocation? yes
Type jfs Relocatable? yes
Intra-policy c (center) Maximum PVs 32
Strict yes Schedule Policy p (Parallel)
Mount Point: /adsmfs Serialize IO no
+---+
| Type "n" if you donot want to create this logical volume. If the LV is not |
| created, no data forthe LV or its filesystem will be restored. | +---+
| Use UP/DOWN ARROW orTab to highlight option to change. Press ESC to return. | +---+
Figure11-9.TheChangeLogicalVolumeAttributeMenu
contains theoriginalsizeof thelogicalvolume.Thisfielddoesnotreflectany changes, soyoucanalways returntothisvalue ifyouinadvertentlychangethe size. TheMinimumsizeindicatestherecommendedminimumsize ofafilesystem thatisrequiredtocontainthefilesystemdata.ThePVs selectedfieldcontains the number ofphysicalvolumescurrentlyassignedtothevolumegroup forthis logicalvolumeand tothelogicalvolume itself.
Thebox attheupper-rightportionofthescreencontains VGSpaceinformation forthevolume grouptowhichthelogicalvolumeisassigned.Thisinformationis updatedtoreflectanychangesthataremadetothelogicalvolumeaffectingits size.Also,if thevolume groupnameischanged,theboxisupdatedtoreflectthe valuesforthenewvolume group.
Thefollowingfields canbechangedforthelogicalvolume:
CreatethisLV?
Indicateswhetherofnotthislogicalvolume(and filesystem)willbe created.Ifyouenter“n”tonotcreatethelogicalvolume,nootherfields canbe changed.Thislogicalvolumeisnotcreatedand,ifinstallinga system,thelogicalvolumeorfilesystemdataisnotrestoredfromthe backupmedia.
Ifthefieldcurrentlycontains“no,”enter“y” tocreatethelogicalvolume, and youcanthenchangeanyotherfield.
Ifyouchangethevalueofthisfield,theVGSpaceinformationboxatthe topofthescreenisupdatedtoreflecttheamountof spaceusedinthe volume groupcontainingthislogicalvolume.
LogicalVolume name
Thenameoftheselectedlogicalvolume.Youcanchangethenameofthe currentlogicalvolumebyenteringa newlogicalvolumenameinthisfield.
Youcanonlyentera logicalvolume thatisnotcurrentlydefinedonthe activesystem oronthebackupmedia.
Volume Groupname
Thevolume groupinwhichthelogicalvolume currentlyexists.Tomove thelogicalvolumeintoa differentvolume group,enterthenew volume groupname. Thevolumegroupnameenteredmustbe currentlyactiveor must beanothervolume grouprecreatedfromthebackupmedia.
Ifthevolumegroup nameischanged,theVG Spaceinformationbox at thetopofthescreenisupdatedtoreflectthenewvolumegroup.
Iftheselectedlogicalvolumecontainsa filesystem,thenyoumustusea JournaledFilesystem Log(jfslog)logicalvolumeinthenew volumegroupto mountthefilesystem.Ifthelogicalvolume ismoved toanewvolume group,the/etc/filesystemsfileisupdatedautomaticallyand thefilesystem ismountedusingthefirstavailable jfsloglogicalvolumeinthenew volume group.Ifthereisnojfslogforthatfilesystemtype inthenew volume group,SysBackwillautomaticallycreateoneforyouprovidedthat thereisenoughdiskspaceallocatedtoyour volumegroup.
Size (inLPs)
Thesize ofthelogicalvolume inlogicalpartitions.Theactualdiskspace requiredbythis logicalvolume isthenumberof logicalpartitions
multipliedbythenumber ofcopies(indicatedinthenext field).Tochange thesizeof thelogicalvolume,enteranew value.
Youcannotchangethisfieldifyouareinstallingthesystemfromapower backup.
Ifthelogicalvolumecontainsa filesystem,thefilesystemiscreatedat the same sizeasthelogicalvolume.
Entering asizesmallerthantheminimumsizedisplayed atthetopofthe screenmightcauseyoutorunoutoffilesystem spacewhenrestoringthe datafromthebackupmedia.Ifyouare installingasystem,over-reducing theroot(/)or/usrfilesystems usuallyresultsin asysteminstallation failure.
Whenyouchangethesize,theVGSpaceboxatthetopofthescreenis updatedtoreflectthenewamount ofspaceusedinthevolumegroup containing thislogicalvolume.
Copies
Thenumber ofcopies(mirrors)ofthelogicalvolume.A“1”indicatesthere isonlyonecopyorthatthelogicalvolume isnotmirrored.Changingthe number ofcopiestogreaterthanonecausesthelogicalvolume tobe
“mirrored” toanotherdisk.Mirroringisusuallyimplemented tokeepa copyof thelogicalvolumeonseparate physicalvolumestoprotectdata againstahardwarefailure.
Thenumber ofcopiescannotbechanged iftheStripeSizeisa valueother than0 unlessthisbackupwascreatedonasystem runningAIX5.1or later.
Ifthenumberof copiesexceeds thenumber ofphysicalvolumesassigned tothelogicalvolume(orvolume groupifnophysicalvolumesare specifically assignedtothislogicalvolume), youwillbe asked“Do you wish to allow more than 1 copy on a single PV? (y/n)”. If you answer
“y”,thenewnumber ofcopiesisaccepted.If“n”, thenew valueis ignored.
Whenyouchangethenumberof copies,theVGSpaceboxatthetopof thescreenisupdatedtoreflectthenewamount ofspaceusedinthe volume groupcontainingthislogicalvolume.
Priority
Thedefaultpriorityinwhichthelogicalvolumewillbecreated.Thisis especially importantifdifferentlogicalvolumesmightbecontendingfor thesameregion ofaparticulardisk.Settingthepriorityofa logical volume toalowernumber givesita higherpriority.
By default,thepriorityissetforlogicalvolumesbasedontheirtypes.The logicalvolumesappearinthelogicalvolume listintheorderinwhichyou wantthemcreated.Tocreateonelogicalvolume beforeanotherlogical volume,changetheprioritytolessthantheother.Thenext timethelogical volumesarelisted,thechangedlogicalvolumeappears inadifferentplace inthelist.
Notethatthisfieldisatwo-digitvalue,sortedfirstbythefirstcharacter, and thenbythesecond.Anentryof“1” issortedafteran entryof“06”,so usetwodigits forallentries.
Type Thecurrentlogicalvolumetype.The typeshouldnotbe changedfor paging, jfslog,dumpdevice,boot logicalvolumes, andlogicalvolumes assignedtoa filesystem.Althoughthetype“jfs”isnormallyusedto indicatefilesystemlogicalvolumes,this andotherlogicalvolumes, except
those specifiedabove,canbechangedtoanydesiredvalueindicatingthe type ofdatacontainedinthelogicalvolume.
Intra-policy
Thecurrentintra-physicalvolumepolicy,a policythatdeterminesthe region ofthephysicalvolumeswhere thelogicalvolumeshouldbe placed.
Thefollowingdiagramindicatestheavailableintra-policies:
spindle
Thisdiagramrepresentsaphysicalvolume (ordiskdrive)andthe
available regions.Inthecenterofthediagramisthespindleof thedisk.To eithersideof thespindleare the“inner-edge” regions;outsideofthose are the“inner-middle”regions.Youcanenteronethefollowing:
e edge(orouter-edge) m middle (orouter-middle)
c center
im inner-middle ie inner-edge
Strict Specify thetype ofstrictnesspolicythatyouwouldlikeforthislogical volume.Validoptionsare:
y Specifythis optionwhenyouwouldlikethelogicalvolume creationtobe strict.
n Specifythis optionwhenyoudonotwantthelogicallyvolume creationtobe strict.
s Specifythis optionwhenyouwantthelogicalvolumecreationto be superstrict.
MountPoint
Thedirectory thatisthemountpointforlogicalvolumescontaining filesystems. Ifthelogicalvolumedoesnotcontainafilesystema dash(-)is shown inthisfieldandthefieldcannotbechanged.
Youcannotchangethisfieldifyouareinstallingthesystemfromapower backup.
Tochangethemountpointofthefilesystem,enteranew directoryhere.
Thedirectory youspecifiedwillbecreated(if itdoesnotalreadyexist) whenthefilesystemiscreated.Ifinstallingthesystem,thedataforthe filesystemisrestoredtothenewmountpoint.For example,if theold mountpointwas /home/filesandthenewmountpointistobe/data/files, then afilepreviouslycalled/home/files/userinfoisrestoredas
/data/files/userinfo.
Ifchanged,the/etc/filesystemsfileisupdatedtoreflectthenew mount pointforthefilesystemsothatallfutureattemptsto mountthefilesystem willdosotothenew mountpoint.
Inter-policy
Thecurrentinter-physicalvolume policy,whichindicates whetherornot thelogicalvolumeshouldbespreadacrossmultipledisks.Thisvaluecan havea differentaffectdependingonthefollowing:
v Ifnophysical volumesare selectedfor thelogicalvolume:a maximum valuespreadsthelogicalvolumeacrosseitherallofthedisksinthe volumegrouporthevalueintheMaximumPVsfield,whicheverisless.
Aminimumvalue usesthefirst diskinthevolumegroupunlessitfills, inwhichcasethenextdiskin thevolume groupisusedforthe remainder.
v Ifyouselectphysicalvolumesforthislogicalvolume,amaximumvalue spreadsthelogicalvolumeacrossallofthedisksselectedfor thelogical volume,nottoexceedthevalue oftheMaximumPVs field.Aminimum valueusesthefirstdiskinthelistshouldbeusedunlessitfills,inwhich casethenextdisk inthelistisused.
v Ifonlyonediskhasbeenselectedforthelogicalvolume orvolume group,this policyhasnoaffect.
v IftheStripesizeissetto anyvalueotherthanzero (0),thispolicyhas noeffect.
StripeSize
Thecurrentstripesize(inK-bytes)or“0” ifthelogicalvolume isnot striped.Stripinga logicalvolume meansthatdataisinter-dispersed
throughoutthespecificphysicalvolumesinblocksofdataindicatedbythe stripesize.StripingusuallybenefitsrandomI/Operformance,buthaving a logicalvolume spreadovermore thanonphysicalvolume causesthe entirelogicalvolumetobe unreadableif anyofthediskscontaining apart ofthelogicalvolumebecomesunavailable.
For alogicalvolumetobe striped,youmustfirst assigntwoormore physical volumestothis logicalvolume,and thenumber oflogical partitions (LPs)must bea multipleofthenumberofdisksselected.You must enterthestripesizeinK-bytes(1024byteblocks).Validvaluesare0, 4, 16,32,64or128.Settingthevalue to“0”indicatesthelogicalvolume willnotbestriped.
Youcannotchangethisfieldifyouareinstallingthesystemfromapower backup, ifthelogicalvolumeistobecreatedusingapartitionmap(Use PP map?field),orifthenumberofCopies isgreaterthan1.
UsePPmap?
Indicateswhetherornottopreservephysicalpartitionmapping.This value issetto“no”bydefault,orto“yes”ifyouselectedtopreserve physical partitionmappingwhenthebackupwascreated.
Select“y” toretaintheexactpriorphysicalpartitionplacementof the logicalvolumeasitwas placedontheoriginalsystem.Creatingalogical volume usingthepartitionmapistypicallyperformedonlyif thelogical volume wasoriginallycreatedusinga partitionmap. Ifthelogicalvolume was notoriginally createdusingamap,doingsonowoftenretainthe partitionfragmentationthatexistsafterlogicalvolumesareperiodically increasedinsize.ThiswouldusuallynegativelyimpactI/Operformance tothis logicalvolume.
Whenyouuseamaptocreatea logicalvolume,thepriorphysical volumesmust stillexistand beofthesamesize.Youcannotchangethe size,number ofcopies,striping,orphysicalvolumesforamappedlogical volume.Also,theIntra-policyandInter-policyareignored.
Select“n”tonotretainthepriorphysicalpartitionmap.Inthis case,the partitionsinthelogicalvolumeare createdcontiguously,resulting,inmost cases,inincreasedI/Operformance.Thelogicalvolume will,however,
continuetobecreated inthegenerallocationasdefinedbythephysical volume list,Intra-policyand Inter-policy.
MWC?
Indicateswhetherornotthemirror-write-consistencycheckingisineffect.If so, thevolume groupstatusareaisupdatedwhenwritesareperformedto a mirroredlogicalpartition.Thisstatusisthen used,inthecaseofadisk orsystem failure,toensurethatall mirroredpartitionsareidenticalwhen thevolumegroup isagain variedon.TurningofftheMWCincreasesI/O performance whenwritingtomirroredlogicalvolumes,butrequiresyouto resynchallmirrorsintheirentiretyincaseof anunexpectedsystem haltto ensureall databetweenthemirrorsisconsistent.
y Specifythis optiontoturnonactivemirror writeconsistency whichensuresdataconsistency amongmirroredcopiesofalogical volume duringnormalI/Oprocessing.
P Specifythis optiontoturnonpassive mirrorwriteconsistency whichensuresdataconsistency amongmirroredcopiesduring volume groupsynchronizationafter asystem interruption.
Note: Thisoption onlyappliestobackupscreatedonsystems runningAIX5.1orlater.
n Specifythis optionwhenyoudonotwanttoenablemirror write consistencyfor thislogicalvolume.
Thisfieldhasnoeffectforsinglecopy(unmirrored)logicalvolumes.
Write-verify?
Indicateswhethera readisperformedafter everywritetoensurethedata was writtenproperly.Turningonthis attributedecreases theI/O
performance whenwritingtoalogicalvolumebutprovides higher
assurancethatdatawas writtenproperlyandisreadable.Enter“y”or“n”
tochangethevalue.
Badblockrelocation?
Indicateswhetherthesoftwareshouldrelocatedatainbadblockswhena writeerroroccurs.Thisactionisnormallytakenbythediskhardware,but thehardwaremightnothavethisfeatureormight nothaveenoughspace forthenumberof blockstorelocate.Turningonthisvaluedoesnotaffect I/Operformance.Tochangethis value,enter“y”or“n”.
Relocatable?
Indicateswhetherornotthislogicalvolumecanbemoved toanew locationwhena volumegroupisreorganizedusingtheAIXreorgvgor migratepvcommand.Ifyoudonotwanttoenablethislogicalvolumeto relocate, enter“y” inthisfield.
Schedule Policy?
Thisoptionchanges theschedulingpolicywhenmorethanonelogical partitioniswritten.
p(Parallel)
Specifythis optiontoestablishaparallel schedulingpolicy.
s(Sequential)
Specifythis optiontoestablishasequentialschedulingpolicy.
ps(ParallelSequential)
Specifythis optiontoestablishaparallel writewith sequentialread
policy.Allmirrorsare writteninparallelbutalways readfromthe first mirrorifthefirstmirror isavailable.
Note: Thisoption onlyappliestobackupscreatedonsystems runningAIX5.1orlater.
pr(Parallel RoundRobin)
Specify thisoptiontoestablishaparallel writeroundrobinread.
Thispolicyissimilartotheparallelpolicyexceptanattemptis madetospreadthereadstothelogicalvolumemore evenlyacross allmirrors
Note: Thisoption onlyappliestobackupscreatedonsystems runningAIX5.1orlater.
SerializeIO?
Usethis optiontoturnsonoroffserializationofoverlappingIOs.If serializationisturnedonthenoverlappingIOsare notallowedona block rangeandonlyasingle IOina blockrangeisprocessedat anyonetime.
Mostapplicationslikefilesystemsand databasesdo serializationso serializationshouldbe turnedoff.Thedefaultfornewlogicalvolumesis off.Validoptionsare “y”foronand“n” foroff.
Note: Thisoption onlyappliestobackupscreatedonsystemsrunningAIX 5.2orlater.
MaximumPVs
Specify themaximum numberofphysicalvolumesontowhichthelogical volume canbeplaced.Thisvalue isusefulinlimitingthenumber of physical volumesusedwhentheInter-policyissettomaximum.
Thevalidvaluesforthisoption isdirectlyimpactedbytheBigEnabled Volume Groupand FactorSizeoptions. PleaserefertoyourAIX documentationtodeterminethemaximum allowedPVsbasedonyour configurationchoices.