Specifications

Administration Guide
268 VMware, Inc.
To change VMkernel configuration options
1Log!in!to!the!VMware!Management!Interface!as!root.
The!Status!Monitor!appears.
2Click!the!Options!tab.
3Click!Advanced!Settings.
4To!change!an!option,!click!the!current!value.
5Enter!the!new!value!in!the!dialog!box!and!click!OK.
For!information!on!changing!these!settings,!see!“Advanced!Settings”!on!page 205.
Detecting All LUNs
By!default,!the!VMkernel!scans!for!only!LUN!0!to!LUN!7!for!every!target.!If!you!are!
using!LUN!numbers!larger!than!7!you!must!change!the!setting!for!the!DiskMaxLUN!
field!from!the!default!of!8!to!the!value!that!you!need.!For!example,!if!you!now!have!LUN
!
numbers!0!to!15!active,!set!this!option!to!16.!Currently,!an!ESX!Server!machine!can!see!
a!maximum!of!128!LUNs!over!all!disk!arrays!on!a!SAN.!
By!default,!the!VMkernel!is!configured!to!support!sparse!LUNs,!that!is,!a!case!where!
some!LUNs!in!the!range!0!
to!N‐1are!not!present,!but!LUN!N!is!present.!If!you!do!not!
need!to!use!such!a!configuration,!change!the!DiskSupportSparseLUN!field!to!0.!This!
change!decreases!the!time!needed!to!scan!for!LUNs.
The!DiskMaskLUNs!configuration!option!allows!the!masking!of!specific!LUNs!on!
specific!HBAs.!Masked!LUNs!
are!not!touched!or!accessible!by!the!VMkernel,!even!
during!initial!scanning.!The!DiskMaskLUNs!option!takes!a!string!comprised!of!the!
adapter!name,!target!ID!and!comma‐separated!range!list!of!LUNs!to!mask.!The!format!
is!as!follows:
<adapter>:<target>:<comma_separated_LUN_range_list>;
For!example,!you!want!to!mask!LUNs!4,!12,!and!54‐65!on!vmhba!1!target!5,!and!LUNs!
3‐12,!15,!and!17‐19!on!vmhba!3!target!2.!To!accomplish!this,!set!the!DiskMaskLUNs!
option!to!the!following:
"vmhba1:5:4,12,54-65;vmhba3:2:3-12,15,17-19;"
The!DiskMaskLUNs!option!subsumes!the!DiskMaxLUN!option!for!adapters!that!have!
a!LUN!mask.!Continuing!the!preceding!example,!there!are!four!adapters,!vmhba0,!
vmhba1,!vmhba2,!and!vmhba3,!and!the!DiskMaxLUN!option!is!set!to!8.!
N
OTE LUN!0!cannot!be!masked.!