IBM 000-8697 User Manual
4-48
IBM Informix OnLine Database Server Administrator’s Guide
Verify OnLine Configuration
Logical logs files that remain on disk and which have not yet been backed up
can still be included in the restore. As part of the restore procedure, OnLine
prompts you to back up those logical log files to tape, so that they can be
rolled forward after the archive tapes have been restored. (This might not be
true if the disks containing the logs failed.)
can still be included in the restore. As part of the restore procedure, OnLine
prompts you to back up those logical log files to tape, so that they can be
rolled forward after the archive tapes have been restored. (This might not be
true if the disks containing the logs failed.)
Verify OnLine Configuration
During the restore, you cannot reinitialize shared memory, add chunks, or
change tape devices. This means that when you begin the restore, the current
OnLine configuration must be compatible with, and accommodate, all
parameter values that have been assigned since the time of the most-recent
archive.
change tape devices. This means that when you begin the restore, the current
OnLine configuration must be compatible with, and accommodate, all
parameter values that have been assigned since the time of the most-recent
archive.
For guidance, use the copies of the configuration file that you create at the
time of each archive. However, do not blindly set all current parameters to
the same values as were recorded at the last archive. Pay attention to three
different groups of parameters:
time of each archive. However, do not blindly set all current parameters to
the same values as were recorded at the last archive. Pay attention to three
different groups of parameters:
■
Shared-memory parameters
■
Mirroring configuration parameters
■
Device parameters
Verify that your current shared-memory parameters are set to the maximum
value assigned since the level-0 archive. For example, if you decreased the
value of
value assigned since the level-0 archive. For example, if you decreased the
value of
USERS
from 45 to 30 sometime since the level-0 archive, you must
begin the restore with
USERS
set at 45, and not at 30, even though the config-
uration file copy for the last archive might have the value of
USERS
set at 30.
(If you do not have a record of the maximum value of
USERS
since the level-
0 archive, set the value as high as you think necessary. You might need to
reassign values to
reassign values to
BUFFERS
,
LOCKS
, and
TBLSPACES
as well, since the
minimum values for these three parameters are based on the value of
USERS
.)
Verify that your current mirroring configuration matches the configuration
that was in effect at the time of the last level-0 archive. Since Informix recom-
mends that you create a level-0 archive after each change in your mirroring
configuration, this should not be a problem. The most critical parameters are
the mirroring parameters that appear in the OnLine configuration file,
that was in effect at the time of the last level-0 archive. Since Informix recom-
mends that you create a level-0 archive after each change in your mirroring
configuration, this should not be a problem. The most critical parameters are
the mirroring parameters that appear in the OnLine configuration file,
MIRRORPATH
and
MIRROROFFSET
.