X-Git-Url: https://git.wh0rd.org/?p=dump.git;a=blobdiff_plain;f=dump%2Fdump.8.in;h=a3763a52ac352d83f7be423d94f55dceb8705231;hp=54f8251c028df83231f439a29a100db00e1051f8;hb=b8f7cbe65e70f2ec792c447995ba00ca360ec0c9;hpb=79e318657e7faa7b2951ff554dc6f1b92624a477 diff --git a/dump/dump.8.in b/dump/dump.8.in index 54f8251..a3763a5 100644 --- a/dump/dump.8.in +++ b/dump/dump.8.in @@ -30,7 +30,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.\" $Id: dump.8.in,v 1.16 2000/08/19 23:48:10 stelian Exp $ +.\" $Id: dump.8.in,v 1.29 2001/07/18 13:12:33 stelian Exp $ .\" .Dd __DATE__ .Dt DUMP 8 @@ -49,9 +49,11 @@ .Op Fl F Ar script .Op Fl h Ar level .Op Fl L Ar label +.Op Fl Q Ar file .Op Fl s Ar feet .Op Fl T Ar date -.Ar file-to-dump +.Op Fl z Ar compression level +.Ar files-to-dump .Nm dump .Op Fl W Li \&| Fl w .Pp @@ -73,28 +75,26 @@ option below for doing remote backups). A dump that is larger than the output medium is broken into multiple volumes. On most media the size is determined by writing until an -end-of-media indication is returned. This can be enforced -by using the -.Fl a -option. +end-of-media indication is returned. .Pp On media that cannot reliably return an end-of-media indication -(such as some cartridge tape drives), -each volume is of a fixed size; -the actual size is determined by the tape size, density and/or -block count options below. +(such as some cartridge tape drives), each volume is of a fixed size; +the actual size is determined by specifying cartridge media, or via the +tape size, density and/or block count options below. By default, the same output file name is used for each volume after prompting the operator to change media. .Pp -.Ar file-to-dump +.Ar files-to-dump is either a mountpoint of a filesystem -or a directory to be backed up as a subset of a filesystem. +or a list of files and directories to be backed up as a subset of a +filesystem. In the former case, either the path to a mounted filesystem or the device of an unmounted filesystem can be used. In the latter case, certain restrictions are placed on the backup: .Fl u -is not allowed and the only dump level that is supported is -.Fl 0 . +is not allowed, the only dump level that is supported is +.Fl 0 +and all the files and directories must reside on the same filesystem. .Pp The following options are supported by .Nm Ns : @@ -115,21 +115,22 @@ copy all files new or modified since the last dump of a lower level. The default level is 9. .It Fl B Ar records -The number of 1 KB blocks per volume. -This option overrides the calculation of tape size -based on length and density. +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. .It Fl a .Dq auto-size . -Bypass all tape length considerations, and enforce writing -until an end-of-media indication is returned. This fits best -for most modern tape drives. Use of this option is particularly -recommended when appending to an existing tape, or using a tape -drive with hardware compression (where you can never be sure about -the compression ratio). +Bypass all tape length calculations, and write +until an end-of-media indication is returned. This works best +for most modern tape drives, and is the default. +Use of this option is particularly recommended when appending to an +existing tape, or using a tape drive with hardware compression +(where you can never be sure about the compression ratio). .It Fl b Ar blocksize The number of kilobytes per dump record. Since the IO system slices all requests into chunks of MAXBSIZE -(typically 64KB), it is not possible to use a larger blocksize +(typically 64kB), it is not possible to use a larger blocksize without having problems later with .Xr restore 8 . Therefore @@ -138,7 +139,8 @@ will constrain writes to MAXBSIZE. The default blocksize is 10. .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. +of 8000 bpi, and a length of 1700 feet. Specifying a cartridge drive +overrides the end-of-media detection. .It Fl e Ar inode Exclude .Ar inode @@ -158,7 +160,8 @@ but full backups retain them. .It Fl d Ar density Set tape density to .Ar density . -The default is 1600BPI. +The default is 1600BPI. Specifying a tape density overrides the +end-of-media detection. .It Fl f Ar file Write the backup to .Ar file ; @@ -199,7 +202,7 @@ The script must return 0 if .Nm should continue without asking the user to change the tape, 1 if .Nm -dump should continue but ask the user to change the tape. +should continue but ask the user to change the tape. Any other exit code will cause .Nm to abort. @@ -240,14 +243,34 @@ notify all operators in the group .Dq operator by means similar to a .Xr wall 1 . +.It Fl Q Ar file +Enable the Quick File Access support. Tape positions for each +inode are stored into the file +.Ar file +which is used by restore (if called with parameter Q and the filename) +to directly position the tape at the file restore is currently working +on. This saves hours when restoring single files from large backups, +saves the tapes and the drive's head. +.Pp +It is recommended to set up the st driver to return logical tape +positions rather than physical before calling dump/restore with +parameter Q. Since not all tape devices support physical tape +positions those tape devices return an error during dump/restore when +the st driver is set to the default physical setting. +Please see the st man page, option MTSETDRVBUFFER, or the mt man +page, on how to set the driver to return logical tape positions. +.Pp +Before calling restore with parameter Q, always make sure the st +driver is set to return the same type of tape position used during the +call to dump. Otherwise restore may be confused. .It Fl s Ar feet -Attempt to calculate the amount of tape needed -at a particular density. +Attempt to calculate the amount of tape needed at a particular density. If this amount is exceeded, .Nm prompts for a new tape. It is recommended to be a bit conservative on this option. -The default tape length is 2300 feet. +The default tape length is 2300 feet. Specifying the tape size +overrides end-of-media detection. .ne 1i .It Fl S Size estimate. Determine the amount of space @@ -300,10 +323,12 @@ The .Fl W option causes .Nm -to print out, for each file system in +to print out, for all file systems in .Pa __DUMPDATES__ , +and regognized file systems in +.Pa /etc/fstab . the most recent dump date and level, -and highlights those file systems that should be dumped. +and highlights those that should be dumped. If the .Fl W option is set, all other options are ignored, and @@ -312,7 +337,18 @@ exits immediately. .It Fl w Is like .Fl W , -but prints only those filesystems which need to be dumped. +but prints only recognized filesystems in +.Pa /etc/fstab +which need to be dumped. +.It Fl z Ar compression level +Compress every block to be written on the tape using zlib library. This +option will work only when dumping to a file or pipe or, when dumping +to a tape drive, if the tape drive is capable of writing variable +length blocks. You will need at least the 0.4b22 version of restore in +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. .El .Pp .Nm Dump @@ -460,16 +496,7 @@ Each reel requires a new process, so parent processes for reels already written just hang around until the entire tape is written. .Pp -.Nm Dump -with the -.Fl W -or -.Fl w -option does not report filesystems that have never been recorded -in -.Pa __DUMPDATES__ , -even if listed in -.Pa /etc/fstab . +The estimated number of tapes is not correct if compression is on. .Pp It would be nice if .Nm @@ -489,17 +516,17 @@ a remote shell program instead. .Sh AUTHOR The .Nm dump/restore -backup suit was ported to Linux's Second Extended File System +backup suite was ported to Linux's Second Extended File System by Remy Card . He maintained the initial versions of dump (up and including 0.4b4, released in january 1997). .Pp Starting with 0.4b5, the new maintainer is Stelian Pop .br -. +. .Sh AVAILABILITY The .Nm dump/restore -backup suit is available from +backup suite is available from .br http://dump.sourceforge.net .Sh HISTORY