- NetBSD Manual Pages
RUMP_EFS(8) NetBSD System Manager's Manual RUMP_EFS(8)
Powered by man-cgi (2021-06-01).
Maintained for NetBSD
by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.
rump_efs -- mount a efs image with a userspace server
rump_efs [options] image mountpoint
NOTE! This manual page describes features specific to the rump(3) file
server. Please see mount_efs(8) for a full description of the available
command line options.
The rump_efs utility can be used to mount efs file systems. It uses
rump(3) and p2k(3) to facilitate running the file system as a server in
userspace. As opposed to mount_efs(8), rump_efs 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_efs 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 prop-
erly 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_efs instead of mount_efs(8). Corrupt file system images commonly
cause the file system to crash the entire kernel, but with rump_efs only
the userspace server process will dump core.
To use rump_efs via mount(8), the flags -o rump and -t efs should be
given. Similarly, rump_efs is used instead of mount_efs(8) if ``rump''
is added to the options field of fstab(5).
p2k(3), puffs(3), rump(3), mount_efs(8)
The rump_efs utility first appeared in NetBSD 5.0.
NetBSD 9.99 November 21, 2010 NetBSD 9.99