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find command lets you copy the entire contents of a directory while preserving the
permissions, times, and ownership of every file and subdirectory. Because find capabilities to specify
complex criteria for files it can create a perfect list of files for cpio, tar, pax and another archiver
Fortunately find has several options that are very useful for structuring the backup:
The typical usage is to combine
find and the
cpio command, as the latter
accepts the list of files via standard input. Tar can do this too with -T - option. Typically
each mount point is backed up in a separate tar or cpio archive.
cd /usr find /usr -mount fstype ext3 - | cpio -pdumv /backup/usr080124.cpi
or, using tar:
find /usr -mount fstype ext3 -print0 | tar -null -cvzf /backup/usr080124.tgzIt is also possible to do incremental backups using -newer option
find /usr -newer /backup/usr080124.tgz -mount fstype ext3 -print0 | tar -null -cvzf /backup/usr_delta080124.tgz
You can also try to avoid errors in backing up named pipes, devises, etc using more complex traversal expressions, for example
find / -mount -fstype ext3 \( -type f -or -type l \) > /tmp/root_list.txt
The problem here is with hard linked files. That that is problem of tar not find. The cpio command is a more sophisticated backup tool than tar. It is harder to use, but is capable of copying special files (such as devices and links) consistently, and will accept wildcard characters when listing the files to be archived.
On higher level you might benefit from exclusion of all files that are not changes in RPMs from which system was installed. This is the approach taken by backup built-in in YAST (it uses tar, not cpio). While tar cannot accept the list of files as standard input it has the -T option which can be used to specify the location of file with list of files to be tarred". Here is how this option is described in the manual:
Instead of giving the names of files or archive members on the command line, you can put the names into a file, and then use the --files-from=file-of-names (-T file-of-names) option to
tar. Give the name of the file which contains the list of files to include as the argument to --files-from. In the list, the file names should be separated by newlines. You will frequently use this option when you have generated the list of files to archive with the
... ... ...
In the file list given by -T option, any file name beginning with - character is considered a
taroption and is processed accordingly.(14) For example, the common use of this feature is to change to another directory by specifying -C option:$ cat list -C/etc passwd hosts -C/lib libc.a $ tar -c -f foo.tar --files-from list
For example if we want to archive file that has size less then 1000 we can first create of list of such files using find and then use tar to created an archive.
find . -size -1K -print > /etc/small-files tar -cvzT /etc/small-files -f little.tgz
You can also compress the archive with gzip of the fly:
tar -zPvcf backup.tar.gz -T list_of_files_to_be_tarred_or_list_of_locations
You will want to use the --label=archive-label (-V archive-label) option to give the archive a volume label, so you can tell what this archive is even if the label falls off the tape, or anything like that.
Unless the file system you are dumping is guaranteed to fit on one volume, you might need to use the --multi-volume (-M) option.
tar has an option of that prevent it from crossing the filesystem (partition)
boundaries: --one-file-system option to prevent from crossing file system
boundaries when storing (sub)directories.
It also has the --incremental (-G) option (see section
to Perform Incremental Dumps).
The options -H, -L or -P may be specified at the start of the command line (if none of these is specified, -P is assumed). If you specify more than one of these options, the last one specified takes effect (the -follow option is equivalent to -L).
-PNever follow symbolic links (this is the default), except in the case of the -xtype predicate.
-LAlways follow symbolic links, except in the case of the -xtype predicate.
-HFollow symbolic links specified in the list of files to search, or which are otherwise specified on the command line.
find would follow a symbolic link, but cannot for any reason (for example, because
it has insufficient permissions or the link is broken), it falls back on using the properties of the
symbolic link itself. Symbolic Links for a more complete description of
how symbolic links are handled.
Option: -mindepth levels
Descend at most levels (a non-negative integer) levels of directories below the command line arguments. -maxdepth 0 means only apply the tests and actions to the command line arguments.
Do not apply any tests or actions at levels less than levels (a non-negative integer). -mindepth 1 means process all files except the command line arguments.
Process each directory's contents before the directory itself. Doing this is a good idea when producing lists of files to archive with
tar. If a directory does not have write permission for its owner, its contents can still be restored from the archive since the directory's permissions are restored after its contents.
This is a deprecated synonym for -depth, for compatibility with Mac OS X, FreeBSD and OpenBSD. The -depth option is a POSIX feature, so it is better to use that.
If the file is a directory, do not descend into it. The result is true. For example, to skip the directory src/emacs and all files and directories under it, and print the names of the other files found:find . -wholename './src/emacs' -prune -o -print
The above command will not print ./src/emacs among its list of results. This however is not due to the effect of the -prune action (which only prevents further descent, it doesn't make sure we ignore that item). Instead, this effect is due to the use of -o. Since the left hand side of the or condition has succeeded for ./src/emacs, it is not necessary to evaluate the right-hand-side (-print) at all for this particular file. If you wanted to print that directory name you could use either an extra -print action:find . -wholename './src/emacs' -prune -print -o -print
or use the comma operator:find . -wholename './src/emacs' -prune , -print
If the -depth option is in effect, the subdirectories will have already been visited in any case. Hence -prune has no effect in this case.
Because -delete implies -depth, using -prune in combination with -delete may well result in the deletion of more files than you intended.
Exit immediately (with return value zero if no errors have occurred). This is different to -prune because -prune only applies to the contents of pruned directories, whilt -quit simply makes
findstop immediately. No child processes will be left running, but no more files specified on the command line will be processed. For example,
find /tmp/foo /tmp/bar -print -quitwill print only /tmp/foo. Any command lines which have been built by -exec ... \+ or -execdir ... \+ are invoked before the program is exited.
Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count. This option is needed when searching filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points. Each directory on a normal Unix filesystem has at least 2 hard links: its name and its . entry. Additionally, its subdirectories (if any) each have a .. entry linked to that directory. When
findis examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (leaf files in the directory tree). If only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed.
If a file disappears after its name has been read from a directory but before
findgets around to examining the file with
stat, don't issue an error message. If you don't specify this option, an error message will be issued. This option can be useful in system scripts (cron scripts, for example) that examine areas of the filesystem that change frequently (mail queues, temporary directories, and so forth), because this scenario is common for those sorts of directories. Completely silencing error messages from
findis undesirable, so this option neatly solves the problem. There is no way to search one part of the filesystem with this option on and part of it with this option off, though. When this option is turned on and find discovers that one of the start-point files specified on the command line does not exist, no error message will be issued.
This option reverses the effect of the -ignore_readdir_race option.
A filesystem is a section of a disk, either on the local host or mounted from a remote
host over a network. Searching network filesystems can be slow, so it is common to make
There are two ways to avoid searching certain filesystems. One way is to tell
only search one filesystem:
Don't descend directories on other filesystems. These options are synonyms.
The other way is to check the type of filesystem each file is on, and not descend directories that are on undesirable filesystem types: Test: -fstype type
True if the file is on a filesystem of type type. The valid filesystem types vary among different versions of Unix; an incomplete list of filesystem types that are accepted on some version of Unix or another is:ext2 ext3 proc sysfs ufs 4.2 4.3 nfs tmp mfs S51K S52K
You can use -printf with the %F directive to see the types of your filesystems. The %D directive shows the device number. See Print File Information. -fstype is usually used with -prune to avoid searching remote filesystems (see Directories).
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Groupthink : Two Party System as Polyarchy : Corruption of Regulators : Bureaucracies : Understanding Micromanagers and Control Freaks : Toxic Managers : Harvard Mafia : Diplomatic Communication : Surviving a Bad Performance Review : Insufficient Retirement Funds as Immanent Problem of Neoliberal Regime : PseudoScience : Who Rules America : Neoliberalism : The Iron Law of Oligarchy : Libertarian Philosophy
War and Peace : Skeptical Finance : John Kenneth Galbraith :Talleyrand : Oscar Wilde : Otto Von Bismarck : Keynes : George Carlin : Skeptics : Propaganda : SE quotes : Language Design and Programming Quotes : Random IT-related quotes : Somerset Maugham : Marcus Aurelius : Kurt Vonnegut : Eric Hoffer : Winston Churchill : Napoleon Bonaparte : Ambrose Bierce : Bernard Shaw : Mark Twain Quotes
Vol 25, No.12 (December, 2013) Rational Fools vs. Efficient Crooks The efficient markets hypothesis : Political Skeptic Bulletin, 2013 : Unemployment Bulletin, 2010 : Vol 23, No.10 (October, 2011) An observation about corporate security departments : Slightly Skeptical Euromaydan Chronicles, June 2014 : Greenspan legacy bulletin, 2008 : Vol 25, No.10 (October, 2013) Cryptolocker Trojan (Win32/Crilock.A) : Vol 25, No.08 (August, 2013) Cloud providers as intelligence collection hubs : Financial Humor Bulletin, 2010 : Inequality Bulletin, 2009 : Financial Humor Bulletin, 2008 : Copyleft Problems Bulletin, 2004 : Financial Humor Bulletin, 2011 : Energy Bulletin, 2010 : Malware Protection Bulletin, 2010 : Vol 26, No.1 (January, 2013) Object-Oriented Cult : Political Skeptic Bulletin, 2011 : Vol 23, No.11 (November, 2011) Softpanorama classification of sysadmin horror stories : Vol 25, No.05 (May, 2013) Corporate bullshit as a communication method : Vol 25, No.06 (June, 2013) A Note on the Relationship of Brooks Law and Conway Law
Fifty glorious years (1950-2000): the triumph of the US computer engineering : Donald Knuth : TAoCP and its Influence of Computer Science : Richard Stallman : Linus Torvalds : Larry Wall : John K. Ousterhout : CTSS : Multix OS Unix History : Unix shell history : VI editor : History of pipes concept : Solaris : MS DOS : Programming Languages History : PL/1 : Simula 67 : C : History of GCC development : Scripting Languages : Perl history : OS History : Mail : DNS : SSH : CPU Instruction Sets : SPARC systems 1987-2006 : Norton Commander : Norton Utilities : Norton Ghost : Frontpage history : Malware Defense History : GNU Screen : OSS early history
The Peter Principle : Parkinson Law : 1984 : The Mythical Man-Month : How to Solve It by George Polya : The Art of Computer Programming : The Elements of Programming Style : The Unix Haters Handbook : The Jargon file : The True Believer : Programming Pearls : The Good Soldier Svejk : The Power Elite
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