Summary
This article describes how to persistently set a tape drive for variable block size mode on Linux.
Resolution
In some distributions of Linux (notably RedHat), the default blocksize for tape devices is not a variable blocksize. You can change this by mounting tapes into the drives and issuing the mt-f <dev file> setblk 0 command. This setting may not persist after the tape is dismounted from the drive. Use stinit to make the change automatic.
- Use the DPX detect utility to get the vendor and model of the tape drive:
<root@echo bin># /opt/BackEx/bin/JB/detect -q
The following is the output of the detect utility:
SCSI Devices found:
------------------
Device Target Adapter Device
File ID LUN ID BUS STATUS Type String
--------- ----- --- ------ --- ------ ---------------------- -------------
/dev/nst0 1 0 0 0 0 Sequental Access Device IBM ULTRIUM-TD1
/dev/nst1 5 0 0 0 0 Sequental Access Device IBM ULTRIUM-TD1
/dev/sg2 6 0 0 0 0 Medium Changer Device PLASMON FTA
- Create the stinit definition file in /etc/stinit.def.
<root@echo bin># cat /etc/stinit.def
manufacturer=IBM model = "ULTRIUM-TD1"
{mode1 blocksize=0 compression=1}
- Initialize the drives by typing in stinit (without loading tapes into the drives). The file will be read at boot time.