8.4.1 Block Size
Determination
Once you have a backup of your data you can restore it
in a number of ways. The flow of the restore process is shown in
Figure 102.
.
Figure 102: Restoring Information
There are a number of problems that you may encounter while you are
restoring data back onto your system. Following is a short list of the problems
that you may encounter while restoring data
- The most general problem that you can face is the incorrect block size
which results in a restore failure. See section
8.4.1 Block Size Determination for how to
recover from this problem.
- Your storage media can be physically damaged. Media errors are recorded
in the error log. If the media can be read successfully with the dd or
the tcopy command, a syntax or usage problem possibly exists. Syntax
or usage problems could include:
- Incorrect archive utility was used.
- cpio backup was not written with ASCII headers and the command
specifies ASCII headers (-c).
- tar command has calculated a checksum different from what is
recorded on the tape indicating that the incorrect volume may be in the drive.
(Use the -i flag to ignore checksums.)
- For tapes, the archive utility does not have enough buffer space to hold
an entire block from the tape file.
- During a restvg command execution (used
for restoring user volume group), you may encounter a failure. Since it expects
the savevg image to be the first image on the tape. This means that
you cannot use a mksysb tape to restore the root volume group through
the restvg command, therefore you can only restore a mksysb
tape in the service mode.
- You may run out of space on a file system restore if the new file system
you created does not have enough space on it.
8.6 References