HP StorageWorks MSL2024, Руководство пользователя и сервисное руководство

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Processor power/drive Minimum RAM/drive Tape drive
3 GHz 2 GB LTO-4 FH
4 GHz 2 GB
LTO-5
In addition to having enough RAM and processing power, ensure that the PCIe bus is at least 64 bit,
has a speed of 66 MHz or better, and is not overloaded by too many high-bandwidth cards. PCIe is
preferred.
Backup type
Each type of backup has its own impact on performance, depending on how well it can keep data
streaming to the tape drive.
File-by-file with a full-featured backup application
Performance impact: VARIABLE .
File-by-file backup with a full-featured backup application can be fast enough if the average file size
is at least 64 k and there are not too many fragmented files. Full-featured backup applications also
offer the best speeds for single file restores and allows for backing up only specific data. Check the
compatibility matrix on the EBS website for a list of full-featured backup applications supported on
your operating system for your Library: http://www.hp.com/go/ebs.
If the average file size is less than 64 k or if the file system is very fragmented, file-by-file backup will
have poor performance. If the file system has a lot of fragmentation, use a de-fragmentation utility to
make the files contiguous again. If the average file size is less than 64 k, HP recommends that you
use a sequential/image backup that backups up the hard drive or LUN image instead of the individual
files. The drawback with sequential/image backups is that they may only be able to restore the entire
disk image and not individual files. If they can restore individual files, the restore operation will be
very slow.
File-by-file with a native application
Performance impact: POOR .
Native backup applications based on tar, cpio, NT Backup, etc. do not have the extra features needed
to manage the bandwidth requirements of the faster tape drives and should only be used to test basic
functionality.
To get the best backup and restore performance, use a full-featured backup application. If the average
file size is less than 64 k, use a sequential/image backup for best performance. However, a
sequential/disk image backup might not allow you to restore individual files or the restore process
will be very slow.
Disk image, flash, or sequential
Performance impact: GOOD .
A disk image or sequential backup backs up an entire disk, partition, or LUN by looking at the disk
sector by sector instead of file by file. The entire disk contents is backed up contiguously, without the
disk seeking, which prevents performance degradation caused by small or fragmented files.
If you are more concerned about backup performance than single-file restore, disk image or sequential
backups can offer a real performance benefit. The disadvantage is that backup and restore operations
HP StorageWorks MSL2024, MSL4048, MSL8048, and MSL8096 Tape Libraries User and service
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