Correct manual page, based on feedback from Bruce Evans.
Reviewed by: Bruce Evans <bde@freebsd.org>
This commit is contained in:
parent
aa6b464e36
commit
e44af4db8d
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=36414
@ -30,7 +30,7 @@
|
|||||||
.\" SUCH DAMAGE.
|
.\" SUCH DAMAGE.
|
||||||
.\"
|
.\"
|
||||||
.\" From: @(#)swapon.8 8.1 (Berkeley) 6/5/93
|
.\" From: @(#)swapon.8 8.1 (Berkeley) 6/5/93
|
||||||
.\" $Id: dumpon.8,v 1.5 1997/02/22 14:32:21 peter Exp $
|
.\" $Id: dumpon.8,v 1.6 1998/05/25 08:54:40 jkoshy Exp $
|
||||||
.\"
|
.\"
|
||||||
.Dd May 12, 1995
|
.Dd May 12, 1995
|
||||||
.Dt DUMPON 8
|
.Dt DUMPON 8
|
||||||
@ -41,45 +41,45 @@
|
|||||||
.Sh SYNOPSIS
|
.Sh SYNOPSIS
|
||||||
.Nm dumpon
|
.Nm dumpon
|
||||||
.Op Fl v
|
.Op Fl v
|
||||||
.Ar swap_device
|
.Ar special_file
|
||||||
|
.Nm dumpon
|
||||||
|
.Op Fl v
|
||||||
|
.Ar off
|
||||||
.Sh DESCRIPTION
|
.Sh DESCRIPTION
|
||||||
.Nm Dumpon
|
.Nm Dumpon
|
||||||
is used to specify a device where the kernel can save a crash dump in
|
is used to specify a device where the kernel can save a crash dump in
|
||||||
the case of a panic.
|
the case of a panic.
|
||||||
.Pp
|
.Pp
|
||||||
The system begins with no dump area configured for safety. If a
|
Calls to
|
||||||
.Dq dumps on
|
.Nm
|
||||||
clause is specified in the kernel configuration file
|
normally occur from the system multi-user initialization file
|
||||||
or if the variable
|
|
||||||
.Dq Li dumpdev
|
|
||||||
in the boot time configuration file
|
|
||||||
.Pa /etc/rc.conf
|
|
||||||
names a dump device, future panics will cause the kernel
|
|
||||||
to save a crash dump on the specified dump device.
|
|
||||||
The dump device must be one of the swap areas
|
|
||||||
specified in the filesystem configuration file
|
|
||||||
.Pa /etc/fstab ,
|
|
||||||
and it must be at least the size of physical memory.
|
|
||||||
.Pp
|
|
||||||
Calls to
|
|
||||||
.Nm dumpon
|
|
||||||
normally occur in the system multi-user initialization file
|
|
||||||
.Pa /etc/rc ,
|
.Pa /etc/rc ,
|
||||||
before the
|
controlled by the
|
||||||
.Xr savecore 8
|
.Dq dumpdev
|
||||||
program is run.
|
variable in the boot time configuration file
|
||||||
|
.Pa /etc/rc.conf .
|
||||||
|
.Pp
|
||||||
|
The size of the specified dump device must be at least 64 KB greater the
|
||||||
|
size of physical memory.
|
||||||
|
.Pp
|
||||||
The
|
The
|
||||||
.Fl v
|
.Fl v
|
||||||
flag can be specified to cause the
|
flag causes
|
||||||
.Nm
|
.Nm
|
||||||
program to be verbose about its activity.
|
to be verbose about its activity.
|
||||||
.Sh NOTES
|
.Sh NOTES
|
||||||
|
One of the system swap devices is usually chosen as the dump device, as
|
||||||
|
swap devices are the most likely to have the required space at dump time.
|
||||||
.Pp
|
.Pp
|
||||||
Hardcoding the dump device using the kernel configuration file
|
The dump device can also be specified at kernel compile time using
|
||||||
is only useful if a kernel crashes before reaching multi-user mode.
|
the
|
||||||
Otherwise, the use of
|
.Dq dumps on
|
||||||
|
clause in the kernel configuration file (see
|
||||||
|
.Xr config 8 ).
|
||||||
|
This is useful when the kernel panics before multi-user mode
|
||||||
|
is reached. Subsequent successful invocations of
|
||||||
.Nm
|
.Nm
|
||||||
to specify the dump device is recommended.
|
will override the compiled in value.
|
||||||
.Pp
|
.Pp
|
||||||
The
|
The
|
||||||
.Nm
|
.Nm
|
||||||
@ -93,7 +93,7 @@ or to
|
|||||||
.Dv NODEV
|
.Dv NODEV
|
||||||
(meaning that no dumps are to be taken) if
|
(meaning that no dumps are to be taken) if
|
||||||
.Ar special_file
|
.Ar special_file
|
||||||
is the text string
|
is the text string:
|
||||||
.Dq Li off .
|
.Dq Li off .
|
||||||
.Sh SEE ALSO
|
.Sh SEE ALSO
|
||||||
.Xr sysctl 3 ,
|
.Xr sysctl 3 ,
|
||||||
@ -109,14 +109,16 @@ is the text string
|
|||||||
.Bl -tag -width /dev/[ws]d?b -compact
|
.Bl -tag -width /dev/[ws]d?b -compact
|
||||||
.It Pa /dev/[ws]d?b
|
.It Pa /dev/[ws]d?b
|
||||||
standard swap areas
|
standard swap areas
|
||||||
.It Pa /etc/fstab
|
|
||||||
static filesystem and swap information
|
|
||||||
.It Pa /etc/rc.conf
|
.It Pa /etc/rc.conf
|
||||||
boot-time system configuration
|
boot-time system configuration
|
||||||
.El
|
.El
|
||||||
.Sh BUGS
|
.Sh BUGS
|
||||||
Because the filesystem layer is already dead by the time a crash dump
|
Because the filesystem layer is already dead by the time a crash dump
|
||||||
is taken, it is not possible to send crash dumps directly to a file.
|
is taken, it is not possible to send crash dumps directly to a file.
|
||||||
|
.Pp
|
||||||
|
.Nm
|
||||||
|
currently allows only devices with minor number 1 to be used as dump
|
||||||
|
devices.
|
||||||
.Sh HISTORY
|
.Sh HISTORY
|
||||||
The
|
The
|
||||||
.Nm
|
.Nm
|
||||||
|
Loading…
Reference in New Issue
Block a user