man full_backup (Administration système) - run a full backup with the afbackup package

NAME

full_backup - run a full backup with the afbackup package

SYNOPSIS

full_backup [ -daG ] [ {+-}LBx ] [ <files> <directories> ... ] [ -C <root-directory> ] [ -F [ -D [ -c <configuration-file> ] [ -W <identity> ] [ -h <backuphosts> ] [ -P <backup-ports> ] [ -I <indexfile-part> ] [ { -N <num-indexes-to-store> ] | -O <max-age-of-indexes-to-store-in-days> } ] [ -z <process-cmd> <unprocess-cmd> ] [ -Z <built-in-compress-level> ] [ -s [ -X <exclude-list-file> ] [ -l <logfile> ] [ -i <startup-info-program> ] [ -b <init-program> ] [ -e <exit-program> ] [ -k <encryption-key-file> ] [ -f <filesystem-types> ] [ -V <var-directory> ] [ -S <cartridge-sets> ] [ -M <server-message-config> ]

DESCRIPTION

This program reads the client-side configuration file and runs (eventually a part of) a full backup of all files and directories specified in the configuration file or on the commandline. It is recommended to setup everything in the configuration file and run this command without any arguments (same applies for incr_backup). If files and/or directories are supplied on the commandline, those specified in the configuration file are overridden. Furthermore the program then behaves slightly different: If backup parts are configured, they are ignored. The timestamp, that is evaluated during incremental backup to determine, whether files have been modified, is not changed. This behaviour reflects the assumption, that supplying files or directories on the commandline is done for testing or other temporary purposes. Modifying the timestamp would confuse the normal regularly running backup mechanism. In these temporary cases the -a option should make sense, see below for details. Be also aware of the -C option's meaning. If the name of a file is preceded with -r, the contents of the file is stored, but not the characteristics of the inode. This is useful for saving raw devices. By default, processing is always turned off. Using -R forces processing of the contents. Preceding a directory name with -m the recursive descent into this directory is limited to the filesystem, where the directory resides. The names of the files and directories, that are stored, are written into logfiles, that comprise of the indexfile-part (-I) and the current total backup counter. This counter is incremented each time a full backup (part 1) starts. A minimum information required to restore after a hard crash having lost everything is piped into the startup-info-program (-i). Whether only a part of a full backup is run depends on the setting of the parameter NumBackupParts (See: afclient.conf(8)). If the configuration file is not supplied explicitly, then it is searched for in the /etc/afbackup and /usr/client/lib, and if not found there the files /etc/buclient.conf, /etc/afbuclient.conf, /etc/afclient.conf and /etc/afbackup/client.conf are tried. Commandline options generally override configuration file settings. Every option described below (except -c) has a corresponding entry in the configuration file, but there are more possible settings in the config file.

-a
Append mode. Do not increment the total backup counter. (See -N)
{+-}B
Perform per-file processing on the stored files (+B) or not (-B) (See: -F)
-b <initprog>
Run the given program before attempting a backup. If the command returns an exit status unequal to 0, no backup is performed (see: -e). Not to be mixed up with option -i
-C <rootdir>
Change to the given directory before starting the backup climbing down into the directories to be stored
-c <configfile>
A different configuration file to use
-D <skip-dirs>
A list of directory name patterns separated by whitespace to ignore for backup. Several must be put into quotes (See: -F and -X)
-d
Detach from the terminal when starting
-e <exitprog>
Run the specified program after finishing. If the command comprises of several words separated by whitespace, it must be put into quotes (See: -i)
-F <skip-files>
A list of filename patterns separated by whitespace to ignore for backup. Several must be put into quotes (See: -D and -X)
-f <fs-types>
A list of filesystem types, separated by whitespace and/or commas. The type names can be prefixed with a plus, what is identical with no prefix, with a dash - or a slash / . No prefix or a plus means, that only files in filesystems of the given type are saved, no others. A minus means, files in a filesystem of the named type are not saved, nonetheless such filesystems are traversed to search for filesystems of other types probably mounted underneath. The slash means, that such filesystems are not even entered or traversed. If the - or + prefix is used, no space is allowed between option -f and it's argument, e.g. -f-nfs
-G
To request a new cartridge. If the current writing position is already at the beginning of a new or reused tape, nothing happens
-h <backuphosts>
The names of the hosts, where a backup server side lives. The list can be separated by commas and/or whitespace. If whitespace is present, quotes are necessary. The hosts are tested for service availability. If a backup server is not ready, the next one is tried. If all are busy, the program waits for a minute and tries again
-I <idx-prefix>
The first part of the filename, the names of the stored files and directories are written to. The current total backup number is appended (that increments each start of a full backup). If these files undergo processing, .z is appended
-i <info-prog>
The command to save startup information. A minimum information to recover from a hard crash is piped into this program (at stdin). If the command comprises of several words, it must be put into quotes. Not to be mixed up with option -b
-k <file>
Use the contents of the given file as encryption key for authenticating to the server
{+-}L
Process the filename list files (+L) or not (-L) (See: -I)
-l <logfile>
Write loggings into the given logfile. A dash - means: no logging, only write to stderr
-M <server-message-config>
The configuration to output messages from the server, that normally are sent only via mail to a maintainer. The first word consisting of the letters b r v and c tells, whether to output messages during backup, restore, verify and copy-tape, respecively. The next words must name the service name or port number of the single stream servers, related to the option -P . For each multi stream service configured with -P or in the configuration file, the respective single stream service must be given here
-N <num-idxes>
The number of filename list files, that is stored over time. A new list is begun at each start of a full backup (except -a is supplied)
-O <maxidxage>
The maximum age of the filename list files (== index files) in days, that is stored. See also option -N . A floating point number is allowed here
-P <portnos>
The port numbers, that are tried to connect at the servers. They must be supplied positionally according to the configured or (with the -h option) given backup servers. The list may be separated by whitespace and/or commas. If whitespace is present, quotes are necessary
-S <cartsets>
The cartridge sets to use, where <cartsets> is a number of a valid cartridge set on the appropriate server side. Default is 1. These must be supplied positionally according to the configured or (with the -h option) given backup servers. The list may be separated by whitespace and/or commas. If whitespace is present, quotes are necessary
-s <noproc>
A list of filename patterns, that no processing is attempted on, what can save time significantly. The list should always be enclosed in quotes
-V <var-dir>
The directory, where varying files are put
-W <identity>
Identify as <id> to the server. This is needed when connecting a multi-stream server to distinguish between the clients. Default is the official hostname of the client. If the client should fake to be a different one than it is in fact, this option must be used. This flag can also be useful e.g. to explicitly store the serverside var-directory, that is crucial for restore and should be saved seperately after all other backup clients are done.
-X <excl-file>
The name of a file, that may exist in any directory containing a list of filename patterns, one per line. All files and directories in that directory matching one of the patterns are exluded from backup (See: -D and -F)
{+-}x
Write CRC32 checksums for each file to tape (+x) or don't do this (-x). This option is ignored, if built-in compression is selected, cause then CRC32 checksumming is already performed
-Z <built-in-compress-level>
If built-in compression should be used, the level can be supplied here. If commands to process and unprocess are also supplied with option -z, then data is first processed by the process command, then by built-in compression. During uncompress it works the other way round
-z <proccmd> <unproccmd>
The commands to use for process and unprocess. If a command comprises of several words, it must be put in quotes

A table of corresponding command line options and configuration file entries, (subsets) accepted by full_backup, incr_backup, restore, verify:

Option
Client configuration file parameter name
+B -B
ProcessBackupedFiles
-C
RootDirectory
-D
DirsToSkip
-e
ExitProgram
-F
FilesToSkip
-f
FilesystemTypes
-h
BackupHost
-I
IndexFilePart
-i
StartupInfoProgram
-k
EncryptionKeyFile
-l
LoggingFile
+L -L
ProcessLogfiles
-N
NumIndexesToStore
-P
BackupPort
-S
CartridgeSet
-s
DoNotProcess
-V
VarDirectory
-W
ClientIdentifier
-X
ExcludeListFile
-x
WriteChecksums
-z
ProcessCmd UnprocessCmd
-Z
Built-inCompressLevel

SIGNALS

When receiving SIGHUP or a single SIGINT (i.e. keyboard Ctrl-C) this program tries to process all pending writes to the server before terminating. That is, if the server is currently not ready to process requests, this program will wait until the server is done or terminates unexpectedly, what will break the connection to all clients. Any connection breakdown will cause a SIGPIPE and thus make a client terminate prematurely. If this program should not wait for the server to terminate properly, but shut down as soon as a consistent status of the client's local persistent data can be achieved, SIGQUIT (== Ctrl-\) or SIGABRT must be sent (once) or SIGINT (== Ctrl-C) 3 times within 2 seconds. Pressing Ctrl-C the second time a respective hint is written to the user. The same can be achieved by sending SIGTERM, which is the default using the kill(1) command. This signal is typically sent to all processes, when a Unix-system goes down in a controlled manner without crashing or fast halt. When SIGINT is received and standard input of this program is not a TTY, the immediate shutdown without waiting for the server is attempted as well. A shutdown like this can be expected to finish quite surely within one second.

FILES

/etc/afbackup/client.conf
Client configuration file
/var/log/afbackup
The directory for logging the client backups
/var/lib/afbackup
Some internal state information of the client backups.
/var/lib/afbackup/num
Here the current total number of backups is stored. The total number of backups is incremented each time a full backup finishes successfully, if not the append mode (option -a) is selected or files and directories are explicitly supplied as arguments. This case is considered an exceptional storing of files, that should not affect counters or timestamps
/var/lib/afbackup/part
If present, it contains the number of the backup part that has recently started. Full backups can be split in pieces if a complete run would take too much time. This can be configured with the parameters NumBackupParts, DirsToBackup1, ...
/var/lib/afbackup/oldmark
The Modification time of this empty file serves as memory for the timestamp, when any full or incremental backup has started before. This should be handled in the file explained next, but due to backward compati- bility issues i will not change this (historical error coming from the earlier used scripts for backup and the use of the find-command with option -newer)
/var/lib/afbackup/newmark
During backup a file holding the timestamp of the backup starting time. The reason, why this timestamp is kept in the filesystem is safety against program crashes
/var/lib/afbackup/level_timestamps
This file contains the timestamps for the backup levels. Each line has the following format: <backup-level>: <incr-backup-starting-time> For each used backup level and the full backup a line will be maintained in this file
/var/lib/afbackup/save_entries
This file holds the patterns of all configuration entries in DirsToBackup, DirsToBackup1, ... for use in subsequent backups. If new entries will be configured, this file allows to automatically switch to full backup from incremental backup, when a new entry in the configuration file is found
/var/lib/afbackup/needed_tapes
This file contains a list of tapes needed for full restore of all files listed in existing filename list files (i.e. index). The number of these files depends on the clientside parameter NumIndexesToStore. After each backup (full or incremental or X-level) a line is added to this file or an existing one is extended to contain the current backup counter and a list of backup levels with the cartridge numbers used during write associated. The format is: <backup-counter>: <backup-level>><tape-list> [ <backup-level>><tape-list> ... ] When running an incremental or differential backup supplying the option -H, entries with a level lower than the current one (or in differential mode equal to the previous) are removed from this list. Thus the tapes from these entries are permitted to be written again (often called "recycled")
/var/lib/afbackup/start_positions
Here for each full or incremental backup within the range required by the parameter NumIndexesToStore the information to retrieve all the data is stored. Each line has the format <backup-counter>: <backup-server> <backup-service> <cartridge-number> <file-number> Having this information everything can be restored in case all other data is lost
/var/lib/afbackup/server_ids
The information, which server network address has which server-ID assiciated. The first two columns contain the hostname and port number, the third the server-ID
/var/lib/afbackup/index_ages
For each existing index file, this file contains a line with the index number in the beginning, followed by a colon and the timestamp of the last modification of that index in seconds since epoch (1.1.1970 0:00). This file is evaluated, if the client side parameter DaysToStoreIndexes is set.

SEE ALSO

AUTHOR

afbackup was written by Albert Fluegel (af@muc.de). This manpage was extracted from the text docs by Christian Meder (meder@isr.uni-stuttgart.de).