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RUMP_SYSVBFS(8) NetBSD System Manager's Manual RUMP_SYSVBFS(8)
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rump_sysvbfs -- mount a sysvbfs image with a userspace server
rump_sysvbfs [options] image mountpoint
NOTE! This manual page describes features specific to the rump(3) file
server. Please see mount_sysvbfs(8) for a full description of the avail-
able command line options.
The rump_sysvbfs utility can be used to mount sysvbfs file systems. It
uses rump(3) and p2k(3) to facilitate running the file system as a server
in userspace. As opposed to mount_sysvbfs(8), rump_sysvbfs does not use
file system code within the kernel and therefore does not require kernel
support except puffs(4). Apart from a minor speed penalty there is no
downside with respect to in-kernel code.
rump_sysvbfs does not require using vnconfig(8) for mounts from regular
files and the file path can be passed directly as the image parameter.
In fact, the use of vnconfig(8) is discouraged, since it is unable to
properly deal with images on sparse files.
In case the image contains multiple partitions, the desired partition
must be indicated by appending the token ``%DISKLABEL:p%'' to the image
path. The letter ``p'' specifies the partition as obtained via
disklabel(8). For example, to mount partition ``e'' from image
/tmp/wd0.img, use ``/tmp/wd0.img%DISKLABEL:e%''.
It is recommended that untrusted file system images be mounted with
rump_sysvbfs instead of mount_sysvbfs(8). Corrupt file system images
commonly cause the file system to crash the entire kernel, but with
rump_sysvbfs only the userspace server process will dump core.
To use rump_sysvbfs via mount(8), the flags -o rump and -t sysvbfs should
be given. Similarly, rump_sysvbfs is used instead of mount_sysvbfs(8) if
``rump'' is added to the options field of fstab(5).
p2k(3), puffs(3), rump(3), mount_sysvbfs(8)
The rump_sysvbfs utility first appeared in NetBSD 5.0.
NetBSD 10.99 November 21, 2010 NetBSD 10.99