3.7.0 HP StorageWorks HP Scalable NAS File Serving Software administration guide - HP Scalable NAS 3.7 for Linux (AG513-96002, October 2009)

6 Configure the SAN
SAN configuration includes the following:
• Import or deport SAN disks. After a disk is imported, it can be used for PSFS
filesystems.
• Change the partitioning on SAN disks.
• Display information about SAN disks.
• Manage multipath I/O.
Overview
SAN configuration requirements
Be sure that your SAN configuration meets the requirements specified in the HP
Scalable NAS File Serving Software installation guide or HP StorageWorks X5500
Network Storage Gateway for Linux setup guide.
Storage Control Layer module
The Storage Control Layer (SCL) module manages shared SAN devices. It operates
as a daemon (SCLd) running on each server in the cluster and is created by the
SANPulse daemon.
The primary function of the SCL module is to ensure that when a server drops out of
the cluster unexpectedly, it is physically disabled from further access to the imported
SAN storage devices. This step enables HP Scalable NAS to perform any needed
filesystem recovery operations to ensure filesystem integrity and then to continue
running safely on the remaining set of servers.
As part of managing shared SAN devices, the SCL is also responsible for providing
each disk with a globally unique device name that all servers in the cluster can use
to access the device.
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