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clientconfig

NAME

client.conf - client side configuration file for afbackup

DESCRIPTION

This file needs not be edited by hand with an editor, instead the program /usr/sbin/afclientconfig can be used. If you are running X, the programs are the same, but start with an 'x'; (Tcl/Tk must be installed): and /usr/sbin/xafclientconfig. The parameters described below are the same for both versions. Entries consist of lines starting with the parameter name, then follows a colon and the value of the parameter. Comment lines can be inserted as desired starting with the # character.

ENTRIES

 BackupHosts

These are the hostnames of the machines where a server side of the backup service resides. Some kind of streamer device must be connected to these machines. The files and directories, that should be saved, are packed, eventually processed somehow, and then sent to the named machines, who writes them to the connected device. The named machines are tested for service availability. If a server is busy, the next one is tried. BackupPorts can be configured in the same order as the host entries supplied here. The servers in this list may be separated by whitespace and/or commas. If a backup server is the same host as the client, the use of the name localhost is encouraged.

BackupPorts

These are the port numbers on the backup server machines, where the backup server processes listen. The default is 2988 or the number found in the file /etc/services (or in NIS if it is configured). Several ports can be supplied, positionally according to the backup server hosts supplied in the BackupHosts parameter. The numbers can be separated by whitespace and/or commas. If fewer numbers are supplied than backup servers, the default port 2988 applies for the rest. If more port numbers are given, the superfluous ones are ignored.

CartridgeSets

The cartridge sets on the server side to use for backups. They must bes legal number between 1 and the number of cartridge sets configured on the appropriate server side. Several sets can be supplied, positionally according to the backup server hosts supplied in the BackupHosts parameter. The numbers can be separated by whitespace and/or commas. If fewer numbers are supplied than backup servers, the default set # 1 applies for the rest. If more cartridge set numbers are given, the superfluous ones are ignored.

PrintServerMessages

By default the server sends messages about current problems or required actions to a maintainer or, if determinable and configured, to the user on the client side. They cannot be seen as output on the client side. When this parameter is set, these messages are also output on the client side. The first word must consist of the letters b, v, r and c i.e. messages are output during backup, verify, restore, and/or copy-tape depending on what letters appear. The next fields must name the respective single stream server ports or service names according to the configured ports in BackupPorts, i.e. wherever a multi stream port appears in the configuration in BackupPorts, here the respective single stream service must be named. If not given the values default to the ones configured in BackupPorts. If this parameter is not properly configured, the messages might not be seen on the client side for technical reasons.

RootDirectory

This is the directory, the backup client changes to before packing the files and directories. Their names should be supplied relative to this directory, e.g. ./home .

DirsToBackup

These are the names of files and directories, that should be saved. Wildcards in the usual manner are allowed (shell- style or glob-style). They should be supplied relative to the working directory, the client changes to when starting. Descending into directories can be limited to the current filesystem by preceding the filename with the four characters .//. or the option -m (and a space). The prefix .//. is stripped off the name before saving. Supplying a filename preceded with the four characters /../ (what makes no sense normally) or the option -r (and a space) forces the file contents to be saved regardless of the file type. This way raw partitions or similar things can be saved. The prefix /../ is stripped off the name before saving. These file contents are by default never processed for safety reasons. If you want to force processing nonetheless, use //../ as prefix or precede the name with the option -R (and a space). To save the output of a command, supply (in double quotes) a triple bar |||, followed by a space and the command. Another triple bar must follow, after that another command doing the opposite of the first one. This command gets the data written by the first one as input at restore time. A triple sharp ### and a comment may follow. A command can be supplied here, whose output is read and used as if it were written here literally. If this is desired, the entry must start with a bar |, followed by a mandatory space and the shell-command to execute. If the pattern %T appears in this command, it is replaced with a specifier for the type of backup: F, if it's a full backup; F<N>, if the full backup is split into several parts with <N> being the part number, e.g. F2; I, if it's an incremental backup; L<N> for a level <N> backup e.g. L5

DirsToBackupX

These are the names of files and directories, that should be saved as part X. Wildcards in the usual manner are allowed (shell-style or glob-style). They should be supplied relative to the working directory the client changes to when starting (See: RootDirectory). Descending into directories can be limited to the current filesystem by preceding the filename with the four characters .//. or the option -m (and a space). The prefix .//. is stripped off the name before saving. Supplying a filename preceded with the four characters /../ (what makes no sense normally) or the option -r (and a space) forces the file contents to be saved regardless of the file type. This way raw partitions or similar things can be saved. The prefix /../ is stripped off the name before saving. These file contents are by default never processed for safety reasons. If you want to force processing nonetheless, use //../ as prefix or precede the name with the option -R (and a space). To save the output of a command, supply (in double quotes) a triple bar |||, followed by a space and the command. Another triple bar must follow, after that another command doing the opposite of the first one. This command gets the data written by the first one as input at restore time. A triple sharp ### and a comment may follow. A command can be supplied here, whose output is read and used as if it were written here literally. If this is desired, the entry must start with a bar |, followed by a mandatory space and the shell-command to execute. If the pattern %T appears in this command, it is replaced with a specifier for the type of backup: F, if it's a full backup; F<N>, if the full backup is split into several parts with <N> being the part number, e.g. F2; I, if it's an incremental backup; L<N> for a level <N> backup e.g. L5 These parameters may only be supplied if the parameter NumBackupParts is set greater than 1 (!). Otherwise they must be commented out to prevent a mismatch.

FilesToSkip

These are the names of files, that should not be saved. Wildcards in the usual manner are allowed (shell-style or glob-style, furthermore path-patterns in the style of GNU's find program with option -path. Note, that e.g. a*d matches ab/cd). E.g. it does not usually make much sense to back up object files, as they can be easily reproduced from existing program sources.

DirsToSkip

These are the names of directories, that should not be saved. Wildcards in the usual manner are allowed (shell-style or glob-style, furthermore path-patterns in the style of GNU's find program with option -path. Note, that e.g. a*d matches ab/cd). E.g. it does not usually make much sense to back up the lost+found directory or such only containing object files, as they can be easily reproduced from existing program sources.

FilesystemTypes

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

ExcludeListFile

A file with the name supplied here can be present in any directory. It should contain a list of file-/directory-names (or glob-style patterns), that should be skipped during backup. Each entry must be in an own line. The given names/patterns are valid only in the same directory, where the file resides. Thus each directory can have it's individual exclusion list."

WriteChecksums

This flag specifies, whether CRC32 checksums are written to the backup or not. Checksumming costs performance but might be desired to achieve additional safety, that the recovered files are intact

UseCTime

When this flag is set, not only a filesystem entry's modification time (mtime) is evaluated when selecting objects to store during incremental or a level X backup, but also the inode change time (ctime). In this mode the filesystem entries access time (atime) is not restored to the value it had before saving it, because that would again change the ctime, thus each incremental backup would result in a full backup

NumBackupParts

If you have to backup a large amount of files and the full backup can't be done during one run (e.g. over a weekend), you can divide the full backup into pieces. This number determines, how many pieces you need. If this number is not equal to 1, you have to supply which files and directories you want to save in which piece. You do so by setting the parameters DirsToBackupX with X equal to the number of the backup part the files belong to.

ProcessCmd

If you want your files to be processed during save (e.g. compressed), you can supply the name of the program that should perform the desired processing here. If you do so, you MUST also supply the appropriate unprocess- program. Note that this program may be specified with options but no shell-like constructions such as pipes, variables or wildcards. This program must read standard input and write to standard output. For pattern replacements see Logging File.

UnprocessCmd

The counterpart to the process program. You must either supply both process- and unprocess-program or neither of them. Like the Process program, the unprocess-program must read standard input and write to standard output. For pattern replacements see LoggingFile.

Built-inCompressionLevel

A number, that specifies the level of built-in compression, if present, otherwise no built-in compression will be performed. If a processing program is also specified, the order of processing is: First the data is piped through the external program and then built-in compression is done. Uncompressing works the other way round.

IndexFilePart

The name of the file where the names of the saved files are stored. The current number is appended to this filename. The number is incremented each time a full backup starts. For pattern replacements see LoggingFile.

IndexProcessCmd

The program to preprocess the index file, in most cases some kind of compression. If this parameter is not set, it defaults to the setting of the ProcessCmd. If you set it, you MUST also supply the appropriate unprocess- program. Note that this program may be specified with options but no shell-like constructions such as pipes, variables or wildcards. This program must read standard input and write to standard output. For pattern replacements see LoggingFile

IndexUnprocessCmd

The counterpart to the index processing program. If not given, it defaults to the setting of the UnprocessCmd. You must either supply both process- and unprocess-program or neither of them. Like the index process program, the unprocess-program must read standard input and write to standard output. For pattern replacements see LoggingFile

ProcessBackupedFiles

This flag specifies, whether the files, that are saved, should be processed by the configured processing program.

ProcessLogfiles

This flag specifies, whether the filename logging files should be processed by the configured processing program.

DoNotProcess

These patterns or filenames specify files, that no processing is attempted on. Normally this is done for all files. This might be unefficient, e.g. compressing files, that are already compressed, so their compression can be suppressed with this parameter. The value of this parameter must be a list separated by whitespace. Double quotes may enclose list elements.

NumIndexesToStore

This number determines how many log files of previous full backups are saved. These files may serve for the restore of older files than those present in the current backup. Of course there must be sufficient space to hold all the data for the backups. It doesn't help to save all the saved filenames but not to have them available on tape.

DaysToStoreIndexes

Instead of the number of index files to be kept (previous parameter), their maximum age can be configured in days (floating point number allowed). Older index files will be automatically removed. If this parameter is configured and the previous one at the same time, the longer duration will be applied to avoid accidental removal of indexes on configuration errors.

NumIndexesToScan

This is the maximum number of index files, that will be scanned during restore. This can be helpful, if it takes too much time to scan through all index files, what is done, if restrictions are given, such as before time, after time or certain tapes. This parameter can be overridden by option -N of afrestore.

DaysToScanIndexes

Instead of configuring the maximum number of index files to be scanned (previous parameter), their maximum age in days can be configured (floating point number allowed). This parameter can be overridden by option -O of afrestore.

CheckRestoreAccessPerms

When this flag is set, during restore started by a normal user (not the superuser) it is checked, whether the user has sufficient access permissions in the directory, where the files are recovered. When relocating using option -C this is default behaviour. With this flag set it will be enforced also when not relocating. This has pros and cons. It might be desirable, that users can also restore their own files in directories owned by root (e.g. at-job files or the CDE calendar stuff). On the other side this might be considered a security problem.

LoggingFile

The name of a file error messages or other notable events are written to. A dash - stands for no logging. The pattern %V will be replaced with the full path to the var-directory, %B with the bin directory, %L with the lib directory, %C with the configuration directory and %I with the logging directory (usually == %V)

ClientIdentifier

The identifier for the client. Default: The official hostname. This entry is required, it several afbackup clients reside on one host and the multi stream server is used. In this case the multi stream server must be able to distinguish the clients to distribute the pieces of backup data on tape correctly. Otherwise the data would be mixed up and be unusable for the reading client. The multi-stream server writes the data to backup piecewise to tape, each chunk preceded with an identifier. This identifier is by default the official hostname of the connected client. If several client programs are running on the same client host, this procedure must fail. Any data prefixed with the name of the client would be delivered to the client program when reading (restore, verify, ...) and thus be a mixture of data previously sent to the server by both client programs with the same identifier (official hostname by default). For this reason the server denies to serve several connected clients with the same identifier. If several afbackup clients should be installed on one host, different client identifiers must be set in their configuration files.

VarDirectory

The directory, where varying files should be put in. These files must not be deleted. The information they contain is necessary for restore.

EncryptionKeyFile

The file containing the encryption key for authenticating the backup client to the server. This file must contain at least 5 characters and must not have read permission for group or world. For pattern replacements see LoggingFile.

LockFile

To prevent client programs from being started several times a lock file is created and this is it's name. For pattern replacements see LoggingFile.

StartupInfoProgram

This is the (shell-) command to run to save the startup information of an incremental or full backup, sometimes called bootstrap information. This program should read the standard input and do something reasonable with it, e.g. append it to some file. The produced information can be used to recover from a hard crash, when the files are lost, that are containing the names of the saved files. Therefore this information should not be saved locally on the client host, but e.g. on an NFS-mounted filesystem, a floppy disc or in a mail-file (then this command should be sth. like: mail someuser). For pattern replacements see LoggingFile.

InitProgram

A (shell-) command to be run before a backup is attempted. If this program returns an exit status unequal to 0, no backup is performed. This parameter makes only sense when backup is started remotely, cause in that case no shell- command can be supplied. If backup is started locally, there is no problem to run whatever is necessery before the backup explicitly. For pattern replacements see LoggingFile.

ExitProgram

This parameter may specify a (shell-) command to run at exit time of a full or incremental backup. The following patterns are replaced as explained: %l by the name of the file containing the filelists
%r by the name of the file containing statistics (this file is automatically removed after execution of this program)
%e by the overall exit status
%i with the minimum restore information
For more pattern replacements see LoggingFile. Under very troublesome circumstances (e.g. several clients are trying to connect a busy single stream server and timeout, or a client program is killed) it might happen, that the ExitProgram is not executed. If you rely on the actions of the ExitProgram you better implement the desired functionality outside of the afbackup system.

FILES

/usr/server/lib/server.conf

Server configuration file

/var/log/afbackup

The directory for logging the server actions

/var/lib/afbackup

Some internal state information of the server.

SEE ALSO

afclientconfig(8), xafclientconfig(8), full_backup(8), incr_backup(8), afverify(8), afrestore(8), xafrestore(8), update_indexes(8), copy_tape(8), afclient.conf(8), afserver(8), afmserver(8), afserver.conf(8), tar(1)

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).