Topics: AIX, Backup & restore, System Admin

How to restore an file from tape

Restoring from tape:

First change the block size of the tape device to 512:

# chdev -l rmt0 -a block_size=512
Check to make sure the block size of the tape drive has been changed:
# tctl -f /dev/rmt0 status
You will receive output similar to this:
rmt0 Available 09-08-00-0,0 LVD SCSI 4mm Tape Drive
attribute     value description                          user_settable

block_size    512   BLOCK size (0=variable length)       True
compress      yes   Use data COMPRESSION                 True
density_set_1 71    DENSITY setting #1                   True
density_set_2 38    DENSITY setting #2                   True
extfm         yes   Use EXTENDED file marks              True
mode          yes   Use DEVICE BUFFERS during writes     True
ret           no    RETENSION on tape change or reset    True
ret_error     no    RETURN error on tape change or reset True
size_in_mb    36000 Size in Megabytes                    False
Change to the /tmp directory (or a directory where you would like to store the / file from the mksysb image) and restore the / file from the tape:
# cd /tmp
# restore -s2 -xqvf /dev/rmt0.1 ./

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