iX V6.5 (30391-90011)

338 Chapter7

Logging and Recovery

Logging Maintenance

Example

LOG ORDERLOG, START

If the log process is stopped using the LOG command, but a database backup copy is not

generated at that time, the RESTART option must be used to resume logging to the same log

ﬁle.

To determine whether or not a log process is running, use the MPE/iX SHOWLOGSTATUS

command to determine the log identiﬁers of active log processes. SHOWLOGSTATUS displays

the percentage of records in the log ﬁle if the logid output is to disk. This information may

be helpful in determining when to perform a CHANGELOG command (see "CHANGELOG

Capability" in this section). The following sample listing was produced by a

SHOWLOGSTATUS command:

:SHOWLOGSTATUS

LOGID CHANGE AUTO USERS STATE CUR-RECS MAX-REC %USED CUR-SET

MYLOG NO NO 4 INACTIVE 100 1000 10% 1

TAPELOG YES 1 INACTIVE 5738 1

ORDERLOG YES YES 2 INACTIVE 500 1000 50% 2

Re-enabling Logging

In the event that logging for roll-forward recovery is disabled and needs to be re-enabled,

the database should be stored with DBSTORE or TurboSTORE/iX 7x24 True-Online Backup

(with ONLINE=START or ONLINE=END option) before logging is re-enabled. This

ensures that the DBSTORE ﬂag and time stamp set when logging was ﬁrst enabled are not

reset when logging is re-enabled.

Setting Database Flags

After logging is initiated, you can allow users to modify the database by running DBUTIL

and enabling the database for access. You should also disable recovery at this time. This

provides a safeguard against unintended recovery if DBRECOV is executed from a stream ﬁle

against several databases simultaneously. For example:

:RUN DBUTIL.PUB.SYS

>>ENABLE ORDERS FOR ACCESS

Access is Enabled

>>DISABLE ORDERS FOR RECOVERY

Recovery is Disabled