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

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IBM Tivoli Storage Manager Implementation Guide
Example 5-2 shows the second phase—extending the database.
Example 5-2 Extending the database
tsm: LOCHNESS_SERVER1>
query db
Available Assigned Maximum Maximum Page Total Used Pct Max.
Space Capacity Extension Reduction Size Usable Pages Util Pct
(MB) (MB) (MB) (MB) (bytes) Pages Util
--------- -------- --------- --------- ------- ------ ----- ---- ----
2,024 1,000 1,024 996 4,096 256,000 1,202 0.5 0.5
tsm: LOCHNESS_SERVER1>
extend db 1024
ANR2248I Database assigned capacity has been extended.
tsm: LOCHNESS_SERVER1>
query db
Available Assigned Maximum Maximum Page Total Used Pct Max.
Space Capacity Extension Reduction Size Usable Pages Util Pct
(MB) (MB) (MB) (MB) (bytes) Pages Util
--------- -------- --------- --------- ------- ------- ----- ---- ----
2,024 2,024 0 2,016 4,096 518,144 1,506 0.3 0.3
After the assigned capacity is extended, the output from query db changes
accordingly. As we have extended the database to use all the defined database
volumes, the maximum extension column shows 0 bytes.
5.2 Recovery log
The recovery log performs two functions, depending on its
mode
setting. Firstly,
the recovery log stores database transactions that have not yet been committed
to the database. Any operation that updates the Tivoli Storage Manager
database is first written to the recovery log. Secondly, if the recovery log mode is
roll forward
, the transaction is cached in the recovery log after it has been
committed. Caching of transactions allows you to replay the transactions at a
later point in time to enhance database recovery, if needed. See 5.3, “Setting the
log mode” on page 196, for more information.
As with its database, Tivoli Storage Manager considers the recovery log as one
logical object, made up of a number of physical files, or
volumes
.