Managing HP Serviceguard for Linux Ninth Edition, April 2009

Storage on Arrays
Figure 3-21 shows LUNs configured on a storage array. Physical disks are configured
by an array utility program into logical units, or LUNs, which are seen by the operating
system.
Figure 3-21 Physical Disks Combined into LUNs
NOTE: LUN definition is normally done using utility programs provided by the disk
array manufacturer. Since arrays vary considerably, you should refer to the
documentation that accompanies your storage unit.
For information about configuring multipathing, see “Multipath for Storage ” (page 96).
Monitoring Disks
Each package configuration includes information about the disks that are to be activated
by the package at startup. If monitoring is used, the health of the disks is checked at
package startup. The package will fail if the disks are not available.
When this happens, the package may be restarted on another node. If auto_run is set
to yes, the package will start up on another eligible node, if it meets all the requirements
84 Understanding Serviceguard Software Components