Operating OnLine 3-21

Change Block Size of Logical Log Tape Device

From the Command Line
To change the value ofLTAPEDEV from the command line, use an editor to
editthe file specified by $INFORMIXDIR/etc/$TBCONFIG. Change the value
ofLTAPEDEV (and LTAPEBLK andLTAPESIZE, if appropriate).
Change Block Size of Logical Log Tape Device
The block size of the logical log tape device is specified as LTAPEBLK in the
configuration file. The block size is expressed in kilobytes.
Youcan change the value of LTAPEBLK while OnLine is in online mode. The
change takes effect immediately.
Specify the largest block size permitted by your tape device.
If the tape device pathname is/dev/null, the block size is ignored.
Ifyou are logged in as user informix, you can change the value of LTAPEBLK
from withinDB-Monitor or from the command line. If you are logged in as
root, you must use the command-line option.
Important: Anytime you change the physical characteristics of the tape device, you
mustcreate a level-0 archive. Otherwise, you might be unable to restore the complete
setof tapes. OnLine cannot switch tape devices during a restore. OnLine expects all
logicallog backup tapes to have the same block size and tape size as were specified at
the time of the most recent level-0 archive.
OnLine does not check the tape device when you specify the block size.
Verifythat the tape device specified in LTAPEDEVcan read the block size that
you specified. If not, you cannot restore the tape.
From DB-Monitor
1. Selectthe Logical-Logs menu, Tape-Parameters option to change the
value ofLTAPEBLK.DB-Monitor displays the current value.
2. Enter the new block size expressed in kilobytes in theBlock Size
field that appears under theLog Tape Device field.