HP-UX Reference (11i v3 07/02) - 1M System Administration Commands A-M (vol 3)

f
frecover(1M) frecover(1M)
(TO BE OBSOLETED)
-X
Recover files relative to the current working directory. Normally
frecover recovers files to
their absolute path name.
EXTERNAL INFLUENCES
Environment Variables
LC_COLLATE determines the order in which frecover
expects files to be stored on the backup device
and the order in which file names are output by the
-I option.
LC_MESSAGES determines the language in which messages are displayed.
If LC_COLLATE and LC_MESSAGES are not specified in the environment or are set to the empty string,
the value of LANG is used as a default for each unspecified or empty variable. If
LANG is not specified or is
set to the empty string, a default of "C" (see lang(5)) is used instead of
LANG. If any internationalization
variable contains an invalid setting,
frecover behaves as if all internationalization variables are set to
"C". See environ(5).
International Code Set Support
Single- and multi-byte character code sets are supported.
WARNINGS
The fbackup, frecover, and ftio commands are deprecated for creating new archives. In a future
HP-UX release, creation of new archives with these commands will not be supported. Support will be con-
tinued for archive retrieval. Use the standard pax command (portable archive interchange) to create
archives. See pax(1).
For incremental backups created prior to installing HP-UX Release 8.0, or for recoveries that do not begin
with the first volume (such as when reading tape 3 first), it is possible for the preceding directories to a
recoverable file to not be on the media. This can happen, for example, if the directories did not change
since the last full backup. If frecover encounters a file on the backup that should be recovered, but it
has not recovered the file’s parent directories from the backup, it prints a message stating that the recovery
will continue with that file, and attempts to create the file’s parent directories as needed.
Use of frecover does not require special privileges. However, if a user does not have access permission
to a given file, the file is not recovered.
In HP-UX 11i Version 3, the maximum value for fields returned from
uname() was increased (from 8 to
256). To accommodate the larger size, a format change was necessary. A new magic number,
FBACKUP*LABEL, was created to distinguish this new format.
Likewise with HP-UX 10.20, HP-UX added support for large files (greater than 2GB) and increased
UID/GIDs (greater than 60,000). The magic number associated with this release through HP-UX 11i Ver-
sion 2 (inclusive) is FBACKUP_LABEL
.
Archives and files with formats and attributes that are unsupported on previous HP-UX releases could
cause severe problems or unpredictable behavior if attempts were made to restore onto these systems. For
this reason,
fbackup creates tapes with a magic number that is only recognized on releases which sup-
port the features and format being archived. This prevents fbackup tape archives from being restored on
earlier HP-UX systems than are supported. frecover still reads all tape formats so that fbackup tape
archives created on earlier HP-UX systems can be restored.
The
fbackup index format now includes the file size in the first field; the previous format simply had the
’#’ character in that field. The implementation provides both forward and backward compatibility between
the old and new index formats. However, the file sizes are used in conjunction with the checkpoints to
increase selective recovery speed on DLT devices, so recovery of an
fbackup volume that does not have
the new index format will not see that performance gain.
When using a DDS tape written with the current release of fbackup to do a partial recovery, frecover
attempts to use the DDS fast-search capability to find files on the tape more quickly. In order to do this,
however, frecover needs to create an in-memory copy of the index, and mark the files on that index
which it needs to recover before actually reading through the tape to find the files. This is done when the
first index is read from the tape, and accounts for a period of time just after recovery is begun where the
tape is inactive while this in-memory index is constructed. The larger the index is, the longer this period
lasts.
The utility set comprised of fbackup and frecover was originally designed for use on systems
equipped with not more than one gigabyte of total file system storage. Although the utilities have no pro-
gramming limitations that restrict users to this size, complete backups and recoveries of substantially
232 Hewlett-Packard Company − 4 − HP-UX 11i Version 3: February 2007