fbackup.1m (2010 09)

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fbackup(1M) fbackup(1M)

(TO BE OBSOLETED)

NAME

fbackup - selectively back up ﬁles

SYNOPSIS

/usr/sbin/fbackup -f

device [-f device ] ... [

-0-9][-nsuvyAEl][-i path ][-e path ]

[

-g graph ][-d path ][

-I path ][-V path ][-c conﬁg ]

/usr/sbin/fbackup -f

device [-f device ] ... [

-R restart ][-nsuvyAEl][-d path ][-I

path ][-V path ][

-c conﬁg ]

Remarks

Note: The

fbackup, frecover, and

ftio commands are deprecated for creating new archives. See

WARNINGS for more information.

DESCRIPTION

fbackup combines features of dump and ftio

to provide a ﬂexible, high-speed ﬁle system backup

mechanism (see dump(1M) and ftio (1)). fbackup selectively transfers ﬁles to an output device. For

each ﬁle transferred, the ﬁle’s contents and all the relevant information necessary to restore it to an

equivalent state are copied to the output device. The output device can be a raw magnetic tape drive (for

example, a DLT tape drive), the standard output, a rewritable magneto-optical disk, or a ﬁle.

The selection of ﬁles to back up is done by explicitly specifying trees of ﬁles to be included or excluded

from an

fbackup session. The user can construct an arbitrary graph of ﬁles by using the

-i or -e

options on the command line, or by using the -g option with a graph ﬁle. For backups being done on a

regular basis, the -g option provides an easier interface for controlling the backup graph. fbackup

selects ﬁles in this graph, and attempts to transfer them to the output device. The selectivity depends on

the mode (full or incremental) in which fbackup is being used.

When doing full backups, all ﬁles in the graph are selected. When doing incremental backups, only ﬁles

in the graph that have been modiﬁed since a previous backup of that graph are selected. If an incremen-

tal backup is being done at level 4 and the

-g option is used, the database ﬁle is searched for the most

recent previous backup at levels 0-3. If a ﬁle’s modiﬁcation time is before the time when the last

appropriate session began and the i-node change time is before the time that same session ended, the ﬁle

is not backed up. All directories lying on the path to a ﬁle that qualiﬁes for the incremental backup will

also be on the backup media, even if the directories do not qualify on their own status.

fbackup is used for incremental backups, a database of past backups must be kept. fbackup

main-

tains this data in the text ﬁle

/var/adm/fbackupfiles/dates

, by default. Note that the directory

/var/adm/fbackupfiles

must be created prior to the ﬁrst time fbackup is used for incremental

backups. The

-d option can be used to specify an alternate database ﬁle. The user can specify to update

this ﬁle when an fbackup session completes successfully. Entries for each session are recorded on

separate pairs of lines. The following four items appear on the ﬁrst line of each pair: the graph ﬁle

name, backup level, starting time, and ending time (both in time() format). The second line of each

pair contains the same two times, but in strftime() format. These lines contain the local equivalent

of STARTED:, the start time, the local equivalent of ENDED:, and the ending time. These second lines

serve only to make the dates ﬁle more readable; fbackup does not use them. All ﬁelds are separated by

white space. Graph ﬁle names are compared character-by-character when checking the previous-backup

database ﬁle to ascertain when a previous session was run for that graph. Caution must be exercised to

ensure that, for example, graph and ./graph are not used to specify the same graph ﬁle because

fbackup treats them as two different graph ﬁles.

The general structure of an

fbackup volume is the same, no matter what type of device is used. There

are some small speciﬁc differences due to differing capabilities of devices. The general structure is as fol-

lows:

• reserved space for ASCII tape label (1024 bytes)

•

fbackup volume header (2048 bytes)

• session index (size in ﬁeld of volume header)

• data

Each ﬁle entry in the index contains the ﬁle size, the volume number and the pathname of the ﬁle. At the

beginning of every volume,

fbackup assumes that all ﬁles not already backed up will ﬁt on that volume,

an erroneous assumption for all but the last volume. Indices are accurate only for the previous volumes

in the same set. Hence, the index on the last volume may indicate that a ﬁle resides on that volume, but

it may not have actually been backed up (for example, if it was removed after the index was created, but

before fbackup attempted to back it up). The only index guaranteed to be correct in all cases is the on-

HP-UX 11i Version 3: September 2010 − 1 − Hewlett-Packard Company 1

Summary of content (8 pages)

PAGE 1
fbackup(1M) fbackup(1M) (TO BE OBSOLETED) NAME fbackup - selectively back up files SYNOPSIS /usr/sbin/fbackup -f device [-f device ] ... [-0-9] [-nsuvyAEl] [-i path ] [-e path ] [-g graph ] [-d path ] [-I path ] [-V path ] [-c config ] /usr/sbin/fbackup -f device [-f device ] ... path ] [-V path ] [-c config ] [-R restart ] [-nsuvyAEl] [-d path ] [-I Remarks Note: The fbackup, frecover, and ftio commands are deprecated for creating new archives. See WARNINGS for more information.
PAGE 2
fbackup(1M) fbackup(1M) (TO BE OBSOLETED) line index (-I option), which is produced after the last volume has been written. Specific differences in the structure of fbackup volumes are listed below: A • When using magnetic tape devices, the main blocks of information (tape label, volume header, index, data) are separated by EOF marks. fbackup also checkpoints the media periodically to enhance error recovery.
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fbackup(1M) fbackup(1M) (TO BE OBSOLETED) • • • • • • • Number of file-reader processes. Maximum number of times fbackup is to retry an active file. Maximum number of bytes of media to use while retrying the backup of an active file. Maximum number of times a magnetic tape volume can be used (supported range: 1 9999). Name of a file to be executed when a volume change occurs. This file must exist and be executable. Name of a file to be executed when a fatal error occurs.
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fbackup(1M) fbackup(1M) (TO BE OBSOLETED) -g graph graph defines the graph file. The graph file is a text file containing the list of file names of trees to be included or excluded from the backup graph. These trees are interpreted in the same manner as when they are specified with the -i and -e options. Graph file entries consist of a line beginning with either i or e, followed by white space, and then the path name of a tree. Lines not beginning with i or e are treated as an error.
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fbackup(1M) fbackup(1M) (TO BE OBSOLETED) Record Size Time Media Use Volume Number This field contains the maximum length in bytes of a data record. This field contains the clock time when fbackup was started. This field contains the number of times the media has been used for backup. Since the information is actually on the media, this field will always contain the value 0. This field contains a # character followed by 3 digits, and identifies the number of volumes in the backup.
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fbackup(1M) fbackup(1M) (TO BE OBSOLETED) /usr/sbin/fbackup -0i /usr -e /usr/lib -f /dev/rtape/tape4QIC150 The second example is more complicated, and assumes the user wants to maintain a database of past fbackup sessions so that incremental backups are possible. If sufficient on-line storage is available, it may be desirable to keep several of the most recent index files on disk. This eliminates the need to recover the index from the backup media to determine if the files to be recovered are on that set.
PAGE 7
fbackup(1M) fbackup(1M) (TO BE OBSOLETED) The use of fbackup for backing up NFS mounted file systems is not guaranteed to work as expected if the backup is done as a privileged user. This is due to the manner in which NFS handles privileged-user access by mapping user root and uid 0 to user nobody, usually uid -2, thus disallowing root privileges on the remote system to a root user on the local system.
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(Notes) A (Notes) fA 8 Hewlett-Packard Company −1− HP-UX 11i Version 3: September 2010