Store dumpdates with timezone

[dump.git] / dump / dump.8.in

diff --git a/dump/dump.8.in b/dump/dump.8.in
index c92f90c3268dc512df280c3c152b2b74569efa31..13fae882b4e12d8c631817a732a4f38d23ad6495 100644 (file)
--- 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 1.44 2002/07/24 14:12:00 stelian Exp $
+.\"    $Id: dump.8.in,v 1.50 2003/03/06 14:35:51 stelian Exp $
 .\"
 .TH DUMP 8 "version __VERSION__ of __DATE__" BSD "System management commands"
 .SH NAME
@@ -42,6 +42,7 @@ dump \- ext2/3 filesystem backup
 [\fB\-B \fIrecords\fR]
 [\fB\-b \fIblocksize\fR]
 [\fB\-d \fIdensity\fR]
+[\fB\-D \fIfile\fR]
 [\fB\-e \fIinode numbers\fR]
 [\fB\-E \fIfile\fR]
 [\fB\-f \fIfile\fR]
@@ -115,17 +116,16 @@ to be used by
 to determine whether a file is in the dump file that is being restored.
 .TP
 .BI \-b " blocksize"
-The number of kilobytes per dump record. Since the IO system slices all
-requests into chunks of 
+The number of kilobytes per dump record. The default blocksize is 10
+and the maximal value is 1024.
+Note however that, since the IO system slices all requests into chunks
+of 
 .B MAXBSIZE
-(typically 64kB), it is not possible to use a larger blocksize without having 
-problems later with
-.BR restore (8).
-Therefore
-.B dump
-will constrain writes to 
-.B MAXBSIZE.
-The default blocksize is 10.
+(which can be as low as 64kB), you can experience problems with
+.BR dump (8)
+and
+.BR restore (8)
+when using a higher value, depending on your kernel and/or libC versions.
 .TP
 .BI \-B " records"
 The number of 1 kB blocks per volume. Not normally required, as
@@ -147,6 +147,11 @@ Set tape density to
 The default is 1600BPI. Specifying a tape density overrides the end-of-media
 detection.
 .TP
+.BI \-D " file"
+Set the path name of the file storing the information about the previous 
+full and incremental dumps. The default location is
+.IR __DUMPDATES__ .
+.TP
 .BI \-e " inodes"
 Exclude 
 .I inodes
@@ -192,8 +197,9 @@ this can be overridden by the environment variable
 .BR RMT .
 .TP
 .BI \-F " script"
-Run script at the end of each tape. The device name and the current volume
-number are passed on the command line. The script must return 0 if 
+Run script at the end of each tape (except for the last one). 
+The device name and the current volume number are passed on the
+command line. The script must return 0 if 
 .B dump
 should continue without asking the user to change the tape, 1 if 
 .B dump
@@ -224,6 +230,8 @@ is useful when running
 .B dump
 on an active filesystem where read errors simply indicate an inconsistency 
 between the mapping and dumping passes.
+.IP
+A value of 0 means that all read errors will be ignored.
 .TP
 .BI \-j "compression level"
 Compress every block to be written on the tape using bzlib library. This option
@@ -359,7 +367,15 @@ determined from looking in
 The format of
 .I date
 is the same as that of
-.BR ctime (3).
+.BR ctime (3)
+followed by an rfc822 timezone specification: either a plus or minus sign
+followed by two digits for the number of hours and two digits for the minutes.
+For example, -0800 for eight hours west of Greenwich or +0230 for two hours
+and a half east of Greenwich. This timezone offset takes into account
+daylight savings time (if applicable to the timezone): UTC offsets
+when daylight savings time is in effect will be different than offsets
+when daylight savings time is not in effect. For backward
+compatibility, if no timezone is specified, a local time is assumed.
 This option is useful for automated dump scripts that wish to dump over a 
 specific period of time. The
 .B \-T
@@ -375,8 +391,12 @@ after a successful dump. The format of
 is readable by people, consisting of one free format record per line:
 filesystem name, increment level and
 .BR ctime (3)
-format dump date. There may be only one entry per filesystem at each level. The
-file
+format dump date followed by a rfc822 timezone specification (see the
+.B \-u
+option for details). If no timezone offset is specified, times are interpreted 
+as local. Whenever the file is written, all dates in the file are converted 
+to the local time zone, without changing the UTC times. There
+may be only one entry per filesystem at each level. The file
 .I __DUMPDATES__
 may be edited to change any of the fields, if necessary.
 .TP
@@ -401,6 +421,8 @@ option causes
 to print out, for all file systems in
 .I __DUMPDATES__ ,
 and regognized file systems in
+.I /etc/mtab
+and
 .IR /etc/fstab .
 the most recent dump date and level, and highlights those that should be 
 dumped. If the
@@ -413,6 +435,8 @@ exits immediately.
 Is like
 .BR \-W ,
 but prints only recognized filesystems in
+.I /etc/mtab
+and
 .I /etc/fstab
 which need to be dumped.
 .TP
@@ -527,6 +551,9 @@ dump date records
 .I /etc/fstab
 dump table: file systems and frequency
 .TP
+.I /etc/mtab
+dump table: mounted file systems
+.TP
 .I /etc/group
 to find group
 .I operator
@@ -536,6 +563,15 @@ to find group
 .BR rmt (8)
 .SH DIAGNOSTICS
 Many, and verbose.
+.SH COMPATIBILITY
+The format of the
+.I __DUMPDATES__
+file has changed in release 0.4b34, however, the file will be read
+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).
 .SH EXIT STATUS
 .B Dump
 exits with zero status on success. Startup errors are indicated with an exit