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

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Chapter 12. Scheduling
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The default Tivoli Storage Manager configuration file specifies a 24-hour cycle
for expiration, with expiration processing beginning 24 hours from when you first
start the server. Unfortunately, this situation is rarely ever satisfactory. Expiration
of inventory can be computationally intensive and it is best scheduled during a
quiet server time to minimize its impact on server operations. It is also helpful to
run inventory expiration before you run reclamation, so that the reclamation
process can consolidate newly expired space.
Therefore, we recommend scheduling the expire inventory command daily, as
shown in Example 12-9. The schedule assumes you have disabled the default
expiration execution as recommended in 7.4, “Enforcing your policy” on
page 282.
Example 12-9 Defining an inventory expiration schedule
tsm: LOCHNESS_SERVER1>
define schedule EXPIRE_INVENTORY type=admin
description="Inventory expiration" cmd="expire inventory" starttime=10:00
active=yes
ANR2577I Schedule EXPIRE_INVENTORY defined.
tsm: LOCHNESS_SERVER1>
q sched expire* t=a
* Schedule Name Start Date/Time Duration Period Day
- ---------------- -------------------- -------- ------ ---
EXPIRE_INVENTORY 02/21/2006 10:00:00 1 H 1 D Any
12.2.5 Defining a reclamation schedule
Data on tapes in sequential access storage pools will eventually expire, leaving
portions of the tapes with empty areas (also known as fragmentation). Over time,
fragmentation can cause many tapes to have very little valid data on them.
Reclamation is the process where the valid data on a number of tapes is
consolidated onto a smaller number of tapes. The tapes that are emptied by the
reclamation process are returned to scratch status for reuse. See “Data Storage”
in IBM Tivoli Storage Management Concepts, SG24-4877.
We recommend controlling when the reclamation process runs using a schedule
that sets and resets the reclamation threshold for each storage pool. Outside of
the scheduled reclamation periods, the REClaim parameter for the storage pool
should remain at 100, disabling reclamation from running. Controlling
reclamation is desirable because it demands heavy use of the tape drives and
might interfere with normal backup or restore operations if allowed to be run by
the server.
Tivoli Storage Manager V5.3 introduces the reclaim stgpool command, which
makes reclamation a one-step process. Previously, you had to update the