ufsdump(1M)						  System Administration Commands					       ufsdump(1M)

NAME

       ufsdump - incremental file system dump

SYNOPSIS

       /usr/sbin/ufsdump [options] [arguments] files_to_dump

DESCRIPTION

       ufsdump backs up all files specified by files_to_dump (usually either a whole file system or files within a file sytem changed after a cer-
       tain date) to magnetic tape, diskette, or disk file.

       The ufsdump command can only be used on unmounted file systems, or those mounted read-only. Attempting to dump a mounted,  read-write  file
       system might result in a system disruption or the inability to restore files from the dump. Consider using the fssnap(1M) command to create
       a file system snapshot if you need a point-in-time image of a file system that is mounted.

       options is a single string of one-letter ufsdump options.

       arguments may be multiple strings whose association with the options is determined by order. That is, the  first  argument  goes  with  the
       first option that takes an argument; the second argument goes with the second option that takes an argument, and so on.

       files_to_dump is required and must be the last argument on the command line. See OPERANDS for more information.

       With most devices ufsdump can automatically detect the end-of-media. Consequently, the d, s, and t options are not necessary for multi-vol-
       ume dumps, unless ufsdump does not understand the way the device detects the end-of-media, or the files are to be restored on a system with
       an older version of the restore command.

OPTIONS

       The following options are supported:

       0-9		       The  "dump  level."  All files specified by files_to_dump that have been modified since the last ufsdump at a lower
			       dump level are copied to the dump_file destination (normally a magnetic tape device). For instance, if a "level	2"
			       dump  was  done	on Monday, followed by a "level 4" dump on Tuesday, a subsequent "level 3" dump on Wednesday would
			       contain all files modified or added since the "level 2" (Monday) backup. A "level 0" dump copies  the  entire  file
			       system to the dump_file.

       a archive_file	       Archive file. Archive a dump table-of-contents in the specified archive_file to be used by ufsrestore(1M) to deter-
			       mine whether a file is in the dump file that is being restored.

       b factor 	       Blocking factor. Specify the blocking factor for tape writes. The default is 20 blocks per write for tapes of  den-
			       sity  less  than  6250BPI (bytes-per-inch). The default blocking factor for tapes of density 6250BPI and greater is
			       64. The default blocking factor for cartridge tapes (c option) is 126. The highest blocking factor  available  with
			       most tape drives is 126. Note: the blocking factor is specified in terms of 512-byte blocks, for compatibility with
			       tar(1).

       c		       Cartridge. Set the defaults for cartridge instead of the standard half-inch reel. This sets the density to  1000BPI
			       and  the blocking factor to 126. Since ufsdump can automatically detect the end-of-media, only the blocking parame-
			       ter normally has an effect. When cartridge tapes are used, and this option is not specified, ufsdump will  slightly
			       miscompute  the	size  of  the  tape. If the b, d, s or t options are specified with this option, their values will
			       override the defaults set by this option.

       d bpi		       Tape density. Not normally required, as ufsdump can detect end-of-media. This parameter can be used to keep a  run-
			       ning  tab  on the amount of tape used per reel. The default density is 6250BPI except when the c option is used for
			       cartridge tape, in which case it is assumed to be 1000BPI per track. Typical values for tape devices are:

			       1/2 inch tape

				   6250 BPI

			       1/4 inch cartridge

				   1000 BPI The tape densities and other options are documented in the st(7D) man page.

       D		       Diskette. Dump to diskette.

       f dump_file	       Dump file. Use dump_file as the file to dump to, instead of /dev/rmt/0. If dump_file is specified  as  -,  dump	to
			       standard output.

			       If the name of the file is of the form machine:device, the dump is done from the specified machine over the network
			       using rmt(1M).  Since ufsdump is normally run by root, the name of the local machine must appear  in  the  /.rhosts
			       file of the remote machine. If the file is specified as user@machine:device, ufsdump will attempt to execute as the
			       specified user on the remote machine. The specified user must have a .rhosts file on the remote machine that allows
			       the user invoking the command from the local machine to access the remote machine.

       l		       Autoload.  When	the  end-of-tape is reached before the dump is complete, take the drive offline and wait up to two
			       minutes for the tape drive to be ready again. This gives autoloading (stackloader) tape drives a chance to  load  a
			       new tape. If the drive is ready within two minutes, continue. If it is not, prompt for another tape and wait.

       L string 	       Sets  the tape label to string, instead of the default none. string may be no more than sixteen characters long. If
			       it is longer, it is truncated and a warning printed; the dump will still be done. The tape label is specific to the
			       ufsdump tape format, and bears no resemblance to IBM or ANSI-standard tape labels.

       n		       Notify  all operators in the sys group that ufsdump requires attention by sending messages to their terminals, in a
			       manner similar to that used by the wall(1M) command. Otherwise, such messages are sent only to the terminals  (such
			       as the console) on which the user running ufsdump is logged in.

       N device_name	       Use device_name when recording information in /etc/dumpdates (see the u option) and when comparing against informa-
			       tion in /etc/dumpdates for incremental dumps. The device_name provided can contain no white  space  as  defined	in
			       scanf(3C) and is case-sensitive.

       o		       Offline.  Take  the  drive offline when the dump is complete or the end-of-media is reached and rewind the tape, or
			       eject the diskette. In the case of some autoloading 8mm drives, the tape is removed from the  drive  automatically.
			       This prevents another process which rushes in to use the drive, from inadvertently overwriting the media.

       s size		       Specify the size of the volume being dumped to. Not normally required, as ufsdump can detect end-of-media. When the
			       specified size is reached, ufsdump waits for you to change the volume. ufsdump interprets the specified size as the
			       length  in feet for tapes and cartridges, and as the number of 1024-byte blocks for diskettes. The values should be
			       a little smaller than the actual physical size of the media (for example, 425 for a  450-foot  cartridge).  Typical
			       values for tape devices depend on the c option, for cartridge devices, and the D option for diskettes:

			       1/2 inch tape

				   2300 feet

			       60-Mbyte 1/4 inch cartridge

				   425 feet

			       150-Mbyte 1/4 inch cartridge

				   700 feet

			       diskette

				   1422 blocks (Corresponds to a 1.44-Mbyte diskette, with one cylinder reserved for bad block information.)

       S		       Size estimate. Determine the amount of space that is needed to perform the dump without actually doing it, and dis-
			       play the estimated number of bytes it will take. This is useful with incremental dumps to determine how	many  vol-
			       umes of media will be needed.

       t tracks 	       Specify	the  number of tracks for a cartridge tape. Not normally required, as ufsdump can detect end-of-media. The
			       default is 9 tracks. The t option is not compatible with the D option. Values for Sun-supported tape devices are:

			       60-Mbyte 1/4 inch cartridge     9 tracks

			       150-Mbyte 1/4 inch cartridge    18 tracks

       T time_wait[hms] 	Sets the amount of time to wait for an autoload command to complete. This option is ignored unless  the  l  option
			       has also been specified. The default time period to wait is two minutes. Specify time units with a trailing h ( for
			       hours), m (for minutes), or s (for seconds). The default unit is minutes.

       u		       Update the dump record. Add an entry to the file /etc/dumpdates, for each  file	system	successfully  dumped  that
			       includes the file system name (or device_name as specified with the N option), date, and dump level.

       v		       Verify. After each tape or diskette is written, verify the contents of the media against the source file system. If
			       any discrepancies occur, prompt for new media, then repeat the dump/verification process. The file system  must	be
			       unmounted. This option cannot be used to verify a dump to standard output.

       w		       Warning.  List  the  file  systems  that have not been backed up within a day. This information is gleaned from the
			       files /etc/dumpdates and /etc/vfstab. When the w option is used, all other options are  ignored.  After	reporting,
			       ufsdump exits immediately.

       W		       Warning	with highlight. Similar to the w option, except that the W option includes all file systems that appear in
			       /etc/dumpdates, along with information about their most recent dump dates and levels. File systems  that  have  not
			       been backed up within a day are highlighted.

OPERANDS

       The following operand is supported:

       files_to_dump   Specifies  the  files  to  dump.  Usually  it  identifies  a  whole  file  system  by  its  raw	device	name (for example,
		       /dev/rdsk/c0t3d0s6). Incremental dumps (levels 1 to 9) of files changed after a certain date only apply	to  a  whole  file
		       system.	Alternatively, files_to_dump can identify individual files or directories. All named directories that may be exam-
		       ined by the user running ufsdump, as well as any explicitly-named files, are dumped. This dump is equivalent to a  level  0
		       dump  of the indicated portions of the filesystem, except that /etc/dumpdates is not updated even if the -u option has been
		       specified. In all cases, the files must be contained in the same file system, and the file system must be local to the sys-
		       tem where ufsdump is being run.

		       files_to_dump is required and must be the last argument on the command line.

       If no options are given, the default is 9uf /dev/rmt/0 files_to_dump.

USAGE

       See largefile(5) for the description of the behavior of ufsdump when encountering files greater than or equal to 2 Gbyte ( 2**31 bytes).

EXAMPLES

       Example 1: Using ufsdump

       The following command makes a full dump of a root file system on c0t3d0, on a 150-MByte cartridge tape unit 0:

       example# ufsdump 0cfu /dev/rmt/0 /dev/rdsk/c0t3d0s0

       The following command makes and verifies an incremental dump at level 5 of the usr partition of c0t3d0, on a 1/2 inch reel tape unit 1,:

       example# ufsdump 5fuv /dev/rmt/1 /dev/rdsk/c0t3d0s6

EXIT STATUS

       While running, ufsdump emits many verbose messages. ufsdump returns the following exit values:

       0	Normal exit.

       1	Startup errors encountered.

       3	Abort - no checkpoint attempted.

FILES

       /dev/rmt/0	       default unit to dump to

       /etc/dumpdates	       dump date record

       /etc/group	       to find group sys

       /etc/hosts	       to gain access to remote system with drive

       /etc/vfstab	       list of file systems

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWcsu			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       cpio(1),  tar(1),  dd(1M),  devnm(1M),  fssnap(1M),  prtvtoc(1M),  rmt(1M), shutdown(1M), ufsrestore(1M), volcopy(1M), wall(1M), scanf(3C),
       attributes(5), largefile(5), st(7D)

NOTES

   Read Errors
       Fewer than 32 read errors on the file system are ignored.

   Process Per Reel
       Because each reel requires a new process, parent processes for reels that are already written hang around until the entire tape is written.

   Operator Intervention
       ufsdump requires operator intervention on these conditions: end of volume, end of dump, volume write error, volume open error or disk  read
       error (if there are more than a threshold of 32). In addition to alerting all operators implied by the n option, ufsdump interacts with the
       operator on ufsdump's control terminal at times when ufsdump can no longer proceed, or if something is grossly wrong. All questions ufsdump
       poses must be answered by typing yes or no, as appropriate.

       Since backing up a disk can involve a lot of time and effort, ufsdump checkpoints at the start of each volume. If writing that volume fails
       for some reason, ufsdump will, with operator permission, restart itself from the checkpoint after a defective volume has been replaced.

   Suggested Dump Schedule
       It is vital to perform full, "level 0", dumps at regular intervals. When performing a full dump, bring the machine down to single-user mode
       using shutdown(1M).  While preparing for a full dump, it is a good idea to clean the tape drive and heads. Incremental dumps should be per-
       formed with the system running in single-user mode.

       Incremental dumps allow for convenient backup and recovery of active files on a more frequent basis, with a minimum of media and time. How-
       ever,  there  are  some	tradeoffs. First, the interval between backups should be kept to a minimum (once a day at least). To guard against
       data loss as a result of a media failure (a rare, but possible occurrence), capture active files on (at least) two sets	of  dump  volumes.
       Another	consideration  is the desire to keep unnecessary duplication of files to a minimum to save both operator time and media storage. A
       third consideration is the ease with which a particular backed-up version of a file can be located and restored.  The  following  four-week
       schedule offers a reasonable tradeoff between these goals.

		     Sun    Mon    Tue	  Wed	 Thu	Fri
	   Week 1:   Full    5	    5	   5	  5	 3
	   Week 2:	     5	    5	   5	  5	 3
	   Week 3:	     5	    5	   5	  5	 3
	   Week 4:	     5	    5	   5	  5	 3

       Although  the  Tuesday  through Friday incrementals contain "extra copies" of files from Monday, this scheme assures that any file modified
       during the week can be recovered from the previous day's incremental dump.

   Process Priority of ufsdump
       ufsdump uses multiple processes to allow it to read from the disk and write to the media concurrently.  Due  to	the  way  it  synchronizes
       between	these  processes,  any	attempt  to  run dump with a nice (process priority) of `-5' or better will likely make ufsdump run slower
       instead of faster.

   Overlapping Partitions
       Most disks contain one or more overlapping slices because slice 2 covers the entire disk. The other slices are of various sizes and usually
       do not overlap. For example, a common configuration places root on slice 0, swap on slice 1, /opt on slice 5 and /usr on slice 6.

       It  should be emphasized that ufsdump dumps one ufs file system at a time. Given the above scenario where slice 0 and slice 2 have the same
       starting offset, executing ufsdump on slice 2 with the intent of dumping the entire disk would instead dump only the root  file	system	on
       slice 0. To dump the entire disk, the user must dump the file systems on each slice separately.

BUGS

       The /etc/vfstab file does not allow the desired frequency of backup for file systems to be specified (as /etc/fstab did). Consequently, the
       w and W options assume file systems should be backed up daily, which limits the usefulness of these options.

SunOS 5.10							    19 Feb 2004 						       ufsdump(1M)