Fujitsu PRIMERGY BX620 S4, Руководство пользователя

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Chapter 9 Operation and Maintenance
Notes on operating backups
Notes on using backups are as follows.
For details, refer to the device manuals.
Head cleaning
Airborne dust and dust from the magnetic media can collect on the head of the magnetic tape device. To
remove this dust, head cleaning must be implemented. Implement head cleaning when the device
displays a cleaning request. Particularly DDS devices require periodic head cleaning, otherwise dust can
cling to the magnetic head, creating a situation that cannot be cleaned using standard head cleaning
methods, and eventually render the device useless.
Also note that there is a limit to how many times the cleaning media can be used.
Using cleaning media that has exceeded its life span will have no cleaning effect. Note these points
especially when performing automatic backups with library devices.
Managing media life span
Media is a consumable product that must be replaced regularly.
Continued use of media exceeding its life span can have negative effects on the device (e.g. increase the
speed of dust accumulation).
The life span of media varies depending on the environment and operating conditions of the device, the
type of backup software used, and other operating conditions, however, it is recommended that they be
replaced sooner than later.
As a guide to when the life span of the media will expire, write the date it was first used on the media.
Rotating media
Perform backup operations using multiple mediums on a rotating basis.
When using a single media cartridge repeatedly, backup data can be temporarily lost in the event the
backup fails. Also if the hard disk fails during backup, the backup data cannot be recovered.
Avoid leaving media in devices
Because the magnetic recording surface of the device is exposed, media can be easily affected by
airborne dust when left inserted for a long period of time. Insert the media before using it, and remove
the media after use, and then restore it to its case.
Also note that some tape devices write management information to the tape when ejecting the media. If
the power were to go out when the media is still in the device, this writing process will not be performed
and the media may become corrupted.
To avoid this, remove the media from the device when turning off the server/device.
Verifying data after backup
Some backup software products provide data verification functions after backup is completed. Such
functions will read and verify the data written to the media after backup is completed. This will increase
the usage of the media, thus reducing the number of times it can be used for backups.
Depending on the hardware being used, some devices perform "read after write" operations on data; note
the points of this section as necessary.