S3QLLOCK(1)							       S3QL							       S3QLLOCK(1)

NAME

       s3qllock - Make trees on an S3QL file system immutable

SYNOPSIS

       s3qllock [options] <directory>

DESCRIPTION

       S3QL  is  a  file  system for online data storage. Before using S3QL, make sure to consult the full documentation (rather than just the man
       pages which only briefly document the available userspace commands).

       The s3qllock command makes a directory tree in an S3QL file system immutable. Immutable trees can no longer be changed in any  way  whatso-
       ever.  You can not add new files or directories and you can not change or delete existing files and directories. The only way to get rid of
       an immutable tree is to use the s3qlrm command.

       s3qllock can only be called by the user that mounted  the  file	system	and  (if  the  file  system  was  mounted  with  --allow-other	or
       --allow-root) the root user. This limitation might be removed in the future (see issue 155).

RATIONALE

       Immutability  is a feature designed for backups. Traditionally, backups have been made on external tape drives. Once a backup was made, the
       tape drive was removed and locked somewhere in a shelf. This has the great advantage that the contents of the backup  are  now  permanently
       fixed. Nothing (short of physical destruction) can change or delete files in the backup.

       In  contrast,  when  backing  up  into an online storage system like S3QL, all backups are available every time the file system is mounted.
       Nothing prevents a file in an old backup from being changed again later on. In the worst case, this may	make  your  entire  backup  system
       worthless.  Imagine  that  your	system	gets infected by a nasty virus that simply deletes all files it can find -- if the virus is active
       while the backup file system is mounted, the virus will destroy all your old backups as well!

       Even if the possibility of a malicious virus or trojan horse is excluded, being able to change a backup after it has been made is generally
       not a good idea. A common S3QL use case is to keep the file system mounted at all times and periodically create backups with rsync -a. This
       allows every user to recover her files from a backup without having to call the system administrator. However, this also allows every  user
       to accidentally change or delete files in one of the old backups.

       Making  a backup immutable protects you against all these problems.  Unless you happen to run into a virus that was specifically programmed
       to attack S3QL file systems, backups can be neither deleted nor changed after they have been made immutable.

OPTIONS

       The s3qllock command accepts the following options:

	  --debug
		 activate debugging output

	  --quiet
		 be really quiet

	  --version
		 just print program version and exit

EXIT STATUS

       s3qllock returns exit code 0 if the operation succeeded and 1 if some error occurred.

SEE ALSO

       The S3QL homepage is at http://code.google.com/p/s3ql/.

       The  full  S3QL	documentation  should  also  be  installed  somewhere  on  your  system,  common  locations  are  /usr/share/doc/s3ql	or
       /usr/local/doc/s3ql.

COPYRIGHT

       2008-2011, Nikolaus Rath

1.11.1								  August 27, 2014						       S3QLLOCK(1)