.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
-.\" $Id: dump.8.in,v 1.37 2002/01/25 14:59:53 stelian Exp $
+.\" $Id: dump.8.in,v 1.42 2002/06/10 14:05:00 stelian Exp $
.\"
.Dd __DATE__
.Dt DUMP 8
.Nd ext2 filesystem backup
.Sh SYNOPSIS
.Nm dump
-.Op Fl 0123456789ackMnqSu
+.Op Fl 0123456789ackMnqSuv
.Op Fl A Ar file
.Op Fl B Ar records
.Op Fl b Ar blocksize
will constrain writes to MAXBSIZE.
The default blocksize is 10.
.It Fl B Ar records
-The number of 1 kB blocks per volume.
-This option overrides the end-of-media detection, and calculation
-of tape size based on length and density. If compression is on this
-limits the size of the compressed output per volume.
+The number of 1 kB blocks per volume. Not normally required, as
+.Nm
+can detect end-of-media. When the specified size is reached,
+.Nm
+waits for you to change the volume. This option overrides
+the calculation of tape size based on length and density.
+If compression is on this limits the size of the compressed
+output per volume.
.It Fl c
Change the defaults for use with a cartridge tape drive, with a density
of 8000 bpi, and a length of 1700 feet. Specifying a cartridge drive
order to extract compressed tapes. Tapes written using compression will
not be compatible with the BSD tape format. The (optional) parameter
specifies the compression level bzlib will use. The default compression
-level is 2.
+level is 2. If the optional parameter is specified, there should be no
+white space between the option letter and the parameter.
.It Fl k
Use Kerberos authentication to talk to remote tape servers. (Only
available if this option was enabled when
to be at most LBLSIZE (currently 16) characters, which must include
the terminating
.Ql \e0 .
+.It Fl m
+If this flag is specified,
+.Nm
+will optimise the output for inodes having been changed but not
+modified since the last dump ('changed' and 'modified' have the
+meaning defined in stat(2)). For those inodes,
+.Nm
+will save only the metadata, instead of saving the entire inode
+contents. Inodes which are either directories or have been modified
+since the last dump are saved in a regular way.
+Uses of this flag must be consistent, meaning that either every dump
+in an incremental dump set have the flag, or no one has it.
+.Pp
+Tapes written using such 'metadata only' inodes will not be compatible
+with the BSD tape format or older versions of
+.Nm restore.
.It Fl M
Enable the multi-volume feature. The name specified with
.Fl f
.Pa __DUMPDATES__
may be edited to change any of the fields,
if necessary.
+.It Fl v
+The
+.Fl v
+(verbose) makes
+.Nm dump
+to print extra information which could be helpful in debug sessions.
.It Fl W
.Nm Dump
tells the operator what file systems need to be dumped.
order to extract compressed tapes. Tapes written using compression will
not be compatible with the BSD tape format. The (optional) parameter
specifies the compression level zlib will use. The default compression
-level is 2.
+level is 2. If the optional parameter is specified, there should be no
+white space between the option letter and the parameter.
.El
.Pp
.Nm Dump
read errors is important, the output from dump can be parsed to look for lines
that contain the text 'read error'.
.Pp
+When a read error occurs,
+.Nm
+prints out the corresponding physical disk block and sector number and the
+ext2 logical block number.
+It doesn't print out the corresponing file name or even the inode number.
+The user has to use
+.Xr debugfs 8 ,
+commands
+.Pa ncheck
+and
+.Pa icheck
+to translate the
+.Pa ext2blk
+number printed out by dump into an inode number, then into a file name.
+.Pp
Each reel requires a new process, so parent processes for
reels already written just hang around until the entire tape
is written.