Formatting tape media for use by Linux

This topic discusses how to format tape media.

The tape media formats used by i5/OS™ and Linux^® are mutually exclusive; i5/OS uses labels, Linux requires a non-labelled tape. Therefore i5/OS and Linux servers cannot share the same tape media.

Note: All new tapes must be initially formatted using the Initialize Tape (INZTAP) CL command. After the tape has been formatted using INZTAP, additional formatting can be done by Linux, if required.

From an i5/OS command line, enter the Initialize Tape (INZTAP) CL command:

INZTAP DEV(TAP01) NEWVOL(*NONE) NEWOWNID(*BLANK) VOL(*MOUNTED) CHECK(*NO) DENSITY(*DEVTYPE) CODE(*EBCDIC)

TAP01 is the name of the tape device. Yours might be different.

DENSITY(*DEVTYPE) gives the best performance; however, if you receive an error with this setting when trying to initialize the tape cartridge, try using DENSITY(*CTGTYPE). If you still receive an error, the tape cartridge is incompatible with your tape drive.

This command produces a non-labelled tape that can be used by Linux backup applications. Note that if tapes are used that are not of the default density for the drive (consult your drive's documentation), you need to reset the tape density after the iSeries™ partition has been restarted.

To reset the tape density after an iSeries partition has been restarted, complete the following steps:

Put a spare tape in the drive. Note that the next step erases all the data on the tape.

Issue the following command:

INZTAP DEV(tape-device-name) CHECK(*NO) Density(*CTGTYPE).

You can now switch the blank tape with the tape that you want to use for Linux backups. Backup applications should now work normally. Failure to initialize a blank tape of the correct density can have unanticipated results. If you regularly switch tape densities you might need to repeat the above steps more often than just after an IPL.