RUMP_LFS(8)

NAME
rump_lfs - mount a lfs image with a userspace server

SYNOPSIS
file-system PUFFS
pseudo-device putter

rump_lfs [options] image mountpoint

DESCRIPTION
NOTE! This manual page describes features specific to the rump(3) file server. Please see mount_lfs(8) for a full description of the available command line options.

The rump_lfs utility can be used to mount lfs file systems. It uses rump(3) and p2k(3) to facilitate running the file system as a server in userspace. As opposed to mount_lfs(8), rump_lfs 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_lfs 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_lfs instead of mount_lfs(8). Corrupt file system images commonly cause the file system to crash the entire kernel, but with rump_lfs only the userspace server process will dump core.

To use rump_lfs via mount(8), the flags -o rump and -t lfs should be given. Similarly, rump_lfs is used instead of mount_lfs(8) if “rump” is added to the options field of fstab(5).

SEE ALSO
p2k(3), puffs(3), rump(3), mount_lfs(8)

HISTORY
The rump_lfs utility first appeared in NetBSD 5.0.