HP XP7 Storage - Manual (Page 187)

Restrictions on Data Retention volumes
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File systems using Data Retention
When setting Data Ret to the UNIX file system volumes, the volumes must be mounted
with the Read Only option after the volumes are unmounted. If Data Ret is set to the
volumes as they are in the mounted status, unexpected behavior may occur in the system. ◦
◦ When using a file system for Write Protect Mode set disk on Windows Server
2003/Windows Server 2008/Windows Server 2012, use the "-x mount" and "-x umount"
RAID Manager command options with the above mentioned procedures.
◦ Data Retention volumes set to Write Protect Mode (Read ONLY) cannot be used for the
Windows NT/Windows 2000 file system (NTFS, FAT).
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LVM(VxVM) on Data Retention
◦ If changing LVM configuration including Data Retention, use the raidvchset -vg command
for setting the status of the target volume checking prohibited temporarily. Also, after the
completion of LVM configuration change, set again the status as checking.
•
Data Retention in HA Cluster Server
◦ If HA Cluster software writes to the metadata at regular intervals to confirm whether its
disks are available or not, then Data Retention should not be used in HA environments.
•
Dynamic disk on Windows systems
◦ Data Retention volumes cannot be used for the dynamic disk, because the dynamic disk
does not handle the volumes set to Write Protect Mode (Read ONLY). Data Retention
volumes must be used for basic disks only.
•
LUN#0
◦ Some operating systems cannot recognize LUNs over LUN#1 if LUN#0 has the Data
Retention "inv" attribute set. This is because some HBA drivers do not scan all LUNs on
a port if LUN#0 is invisible.
Database Validator
Database Validator prevents data corruption in an Oracle database by checking Oracle data
validation before an Oracle data block is written on a disk.
•
Data Block corruption: This occurs when Oracle data is corrupted by some intervening software
layer and/or hardware components. The RAID storage system can check the validity of the
data block before the Oracle data block is written to disk.
•
Data block address corruption: The OS (file system, LVM, Disk driver) may write blocks to the
wrong location. The RAID storage system can check the validity of the data block address to
verify that the Oracle data block is written to the correct location on disk.
•
Protection of Oracle volume: Oracle data files might be overwritten by a non-Oracle application
or by human operation using a command. The RAID storage system can protect volumes
storing Oracle files by preventing the volumes from being modified by another application or
by human error.
Data protection operations 187