IBM E16RMLL-I - Tivoli Storage Manager, Руководство по внедрению

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Chapter 2. Implementation planning
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Tivoli Storage Manager implementations that are small (small number of clients
managing a small amount of data) do not see much benefit from collocation, due
to the small number of tapes required for any restore. Large Tivoli Storage
Manager implementations often collocate both onsite and off-site files due to the
amount of data required for the restore of a client.
Tape drive capacity is a consideration for collocation. To use the minimum
number of tapes, each tape must be used to its maximum capacity. Smaller
capacity tapes will tend to fill completely even with small clients. In this case,
collocation may be useful. With large capacity tape devices and collocation, a
small client may not be able to fill a tape. With a large number of clients,
significant numbers of tape volumes may be required.
2.3.9 Off-site collocation
Determine whether you want to use off-site collocation. Off-site collocation is
usually rarely used, as it greatly increases the number of tapes that need to be
sent off-site.
2.3.10 Image backup retention
Determine how long you want to keep an image backup. Consider your restore
time frame and balance the criticality of a full file space restore, compared with a
single or a small number of files. Image backups can be very useful for quick
restore of large file systems. However, this process will take longer, depending
on how many changes there have been to the file system since the last image
backup. A rule of thumb is to keep at least one weekly image for small servers
and a monthly image for bigger servers (or more frequently if change rates in the
file system are high).
More than 50 clients, each 10 GB storage No No
More than 50 clients, each 100 GB or more Yes Yes/No
Limited disk or tape resources No No
Workstations No No
Database, print, and file servers Yes Yes
Onsite
collocation Off-site
collocation