X-Git-Url: https://git.wh0rd.org/?p=dump.git;a=blobdiff_plain;f=dump%2Fdump.8.in;h=0a272e9892c3aa6d520c32b6c3e149f391834c78;hp=487302d89272b94faadce9e3e18bd003f1103b69;hb=aeb0b047a189fc657ffabbfd108f189752bf718c;hpb=28ba5caee0ed25d3b38da769967173e5710bc10c diff --git a/dump/dump.8.in b/dump/dump.8.in index 487302d..0a272e9 100644 --- a/dump/dump.8.in +++ b/dump/dump.8.in @@ -26,7 +26,7 @@ .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" -.\" $Id: dump.8.in,v 1.56 2004/04/21 08:55:48 stelian Exp $ +.\" $Id: dump.8.in,v 1.62 2009/06/18 09:40:03 stelian Exp $ .\" .TH DUMP 8 "version __VERSION__ of __DATE__" BSD "System management commands" .SH NAME @@ -57,9 +57,6 @@ dump \- ext2/3 filesystem backup .PP .B dump [\fB\-W \fR| \fB\-w\fR] -.PP -(The 4.3BSD option syntax is implemented for backward compatibility but is not -documented here.) .SH DESCRIPTION .B Dump examines files on an ext2/3 filesystem and determines which files need to be @@ -90,14 +87,15 @@ The following options are supported by .B dump: .TP .BI \-level# -The dump level (any integer). A level 0, full backup, guarantees the -entire file system is copied (but see also the +The dump level (any integer). A level 0, full backup, specified by +.B \-0 +guarantees the entire file system is copied (but see also the .B \-h option below). A level number above 0, incremental backup, tells .B dump to copy all files new or modified since the last dump of a lower level. The -default level is 9. Historically only levels 0 to 9 were usable in +default level is 0. Historically only levels 0 to 9 were usable in dump, this version is able to understand any integer as a dump level. .TP .BI \-a @@ -286,6 +284,12 @@ 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. .IP +If you use this option, be aware that many programs that unpack +files from archives (e.g. tar, rpm, unzip, dpkg) may set files' +mtimes to dates in the past. Files installed in this way may not be +dumped correctly using "dump -m" if the modified mtime is earlier +than the previous level dump. +.IP Tapes written using such 'metadata only' inodes will not be compatible with the BSD tape format or older versions of .B restore. @@ -431,7 +435,7 @@ option causes .B dump to print out, for all file systems in .I __DUMPDATES__ , -and regognized file systems in +and recognized file systems in .I /etc/mtab and .IR /etc/fstab . @@ -517,8 +521,8 @@ Always start with a level 0 backup, for example: This should be done at set intervals, say once a month or once every two months, and on a set of fresh tapes that is saved forever. .IP \(em -After a level 0, dumps of active file systems are taken on a daily basis, using -a modified Tower of Hanoi algorithm, with this sequence of dump levels: +After a level 0, dumps of active file systems are taken on a daily basis, +with this sequence of dump levels: .RS 14 .B 3 2 5 4 7 6 9 8 9 9 ... .RE @@ -530,6 +534,15 @@ set of tapes per dumped file system is used, also on a cyclical basis. .PP After several months or so, the daily and weekly tapes should get rotated out of the dump cycle and fresh tapes brought in. +.PP +Another backup strategy is the Tower of Hanoi sequence, which reuses +older tapes in a way that for newer dates the available restore points +are more frequent, then for older dates (see +http://en.wikipedia.org/wiki/Backup_rotation_scheme for additional +information). +.PP +(The 4.3BSD option syntax is implemented for backward compatibility but is not +documented here.) .SH ENVIRONMENT .TP .B TAPE @@ -592,7 +605,7 @@ correctly with either pre-0.4b34 or 0.4b34 and later versions of .B dump provided that the machine on which .B dump -is run did not change timezones (which should be a fairly rare occurence). +is run did not change timezones (which should be a fairly rare occurrence). .SH EXIT STATUS .B Dump exits with zero status on success. Startup errors are indicated with an exit @@ -609,7 +622,7 @@ from dump can be parsed to look for lines that contain the text 'read error'. When a read error occurs, .B dump prints out the corresponding physical disk block and sector number and the -ext2/3 logical block number. It doesn't print out the corresponing file name or +ext2/3 logical block number. It doesn't print out the corresponding file name or even the inode number. The user has to use .BR debugfs (8), commands @@ -646,7 +659,7 @@ The backup suite was ported to Linux's Second Extended File System by Remy Card . He maintained the initial versions of .B dump -(up and including 0.4b4, released in january 1997). +(up and including 0.4b4, released in January 1997). .PP Starting with 0.4b5, the new maintainer is Stelian Pop . .SH AVAILABILITY