dump(8)'s manual page is confusing in its use of records, blocks,
blocksizes, etc does not give the default of -b only mentiones rdump in the NAME section uses both filesystem and file system in similar contexts PR: 34248 Submitted by: Gary W. Swearingen <swear@blarg.net> MFC after: 3 days
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2020-12-20 02:59:44 +00:00
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@ -53,7 +53,11 @@
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.Op Fl T Ar date
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.Ar filesystem
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.Nm
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.Op Fl W Li \&| Fl w
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.Fl W | Fl w
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.Pp
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.Nm rdump
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is an alternate name for
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.Nm .
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.Pp
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.in \" XXX
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(The
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@ -83,10 +87,16 @@ On media that cannot reliably return an end-of-media indication
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(such as some cartridge tape drives)
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each volume is of a fixed size;
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the actual size is determined by the tape size and density and/or
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block count options below.
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.Fl B
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options.
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By default, the same output file name is used for each volume
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after prompting the operator to change media.
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.Pp
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The filesystem to be dumped is specified by the argument
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.Ar filesystem
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as either its device-special file or its mount point
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(if that is in a standard entry in /etc/fstab).
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.Pp
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The following options are supported by
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.Nm :
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.Bl -tag -width Ds
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@ -112,11 +122,15 @@ recommended when appending to an existing tape, or using a tape
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drive with hardware compression (where you can never be sure about
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the compression ratio).
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.It Fl B Ar records
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The number of 1 KB blocks per volume.
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The number of kilobytes per output volume, except that if it is
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not an integer multiple of the output block size,
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the command uses the next smaller such multiple.
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This option overrides the calculation of tape size
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based on length and density.
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.It Fl b Ar blocksize
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The number of kilobytes per dump record.
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The number of kilobytes per output block, except that if it is
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larger than 64, the command uses 64. (See the BUGS section.)
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The default block size is 10.
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.It Fl c
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Change the defaults for use with a cartridge tape drive, with a density
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of 8000 bpi, and a length of 1700 feet.
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@ -343,8 +357,7 @@ Always start with a level 0 backup, for example:
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This should be done at set intervals, say once a month or once every two months,
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and on a set of fresh tapes that is saved forever.
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.It
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After a level 0, dumps of active file
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systems are taken on a daily basis,
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After a level 0, dumps of active filesystems are taken on a daily basis,
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using a modified Tower of Hanoi algorithm,
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with this sequence of dump levels:
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.Bd -literal -offset indent
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@ -404,7 +417,7 @@ is written.
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Currently,
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.Xr physio 9
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slices all requests into chunks of 64 KB. Therefore, it is
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impossible to use a larger tape blocksize, so
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impossible to use a larger output block size, so
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.Nm
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will prevent this from happening.
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.Pp
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