.\"	$NetBSD: rump.halt.1,v 1.2 2010/12/12 17:15:16 pooka Exp $
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.\"	@(#)reboot.8	8.1 (Berkeley) 6/9/93
.\"
.Dd December 12, 2010
.Dt RUMP.HALT 1
.Os
.Sh NAME
.Nm rump.halt
.Nd halt a rump kernel
.Sh SYNOPSIS
.Nm
.Op Fl dhn
.Sh DESCRIPTION
The
.Nm
utility exits a rump kernel.
The file system cache, if present, is flushed.
Since a rump kernel does not control its clients, they are not
directly affected by
.Nm .
However, they will be unable to request further services from the
halted rump kernel.
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl d
Create a core dump.
The core file is saved according to standard userland program
coredump rules, and can be later examined with a debugger.
.It Fl h
By default the process hosting the rump kernel exits.
Using this option shuts down rump kernel activity, but does not
cause the hosting process to exit.
.It Fl n
Do not flush the file system cache.
This option should be used with extreme caution.
It can be used if a virtual disk or a virtual processor is virtually on fire.
.El
.Sh SEE ALSO
.Xr rump 3
.Sh HISTORY
The
.Nm
command appeared in
.Nx 6.0 .
.Sh CAVEATS
While using
.Fl h
makes it impossible to issue further system calls, it does not necessarily
stop all activity in a rump kernel.
It is recommended this option is used only for debugging purposes.