Specifications

VMware, Inc. 267
Chapter 9 Storage and File Systems
though!these!FC!adapters!are!dedicated!to!virtual!machines,!the!LUNs!on!the!SANs!are!
visible!to!system!management!agents!on!the!service!console.
Configuring VMFS Volumes on SANs
Make!sure!that!only!one!ESX!Serv er!system!has!access!to!the!SAN!while!you!are!using!
the!VMware!Management!Interface!to!configure!the!SAN!and!format!the!VMFS‐2!
volumes.!
After!you!finish!the!configuration,!make!sure!all!partitions!on!the!physically!shared!
SAN!disk!are!set!for!public!or
!shared!access!for!access!by!multiple!ESX!Server!systems.!
See!“VMFS!Accessibility”!on!page 248.
For!information!on!configuring!SANs,!scanning!for!LUNs,!and!setting!persistent!
bindings!through!the!VMware!Management!Interface,!see!“Storage!Management”!on!
page 196.
Scanning for Devices and LUNs
ESX!Server!scans!for!devices,!and!LUNs!on!these!devices,!whenever!a!Fibre!Channel!
driver!is!loaded.!You!can!manually!initiate!a!scan!through!the!VMware!Management!
Interface!or!by!using!the!cos-rescan.sh!command.
VMware!recommends!using!cos-rescan.sh,!because!it!is!easier!to!use!with!certain!FC!
adapters!than!vmkfstools.
To
!use!cos-rescan.sh,!enter!the!command!at!a!shell!prompt.
You!may!want!to!rescan!devices!or!LUNs!whenever!you!add!a!new!disk!array!to!the!
SAN!or!create!new!LUNs!on!a!disk!array.!You!may!also!want!to!rescan!LUNs!when!you!
change!the!LUN!masking!on!a!
disk!array.
Changing VMkernel Configuration Options for SANs
To!use!all!storage!devices!on!your!SAN,!you!might!need!to!change!some!VMkernel!
configuration!options.!
N
OTE You!can!have!only!one!VMFS!volume!per!LUN.
NOTE If!you!are!using!multipathing!with!multiple!FC!HBAs,!run!this!command!on!all!of!the!
FC!HBAs.!If,!after!your!rescan,!you!see!new!LUNs!and!they!have!VMFS!volumes,!you!
will!see!the!appropriate!subdirectories!when!you!view!the!contents!of!the!/vmfs!
directory.