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.Dd March 3, 2014
.Dt RUMPFS 4
.Os
.Sh NAME
.Nm rumpfs
.Nd rump kernel root file system
.Sh LIBRARY
rump kernel (librumpvfs, \-lrumpvfs)
.Sh DESCRIPTION
.Nm
is a simple in-memory file system for rump kernels.
It is automatically mounted as the root file system of a rump kernel
at boot time, provided that the VFS faction is configured into the rump
kernel instance.
.Pp
The three main features of
.Nm
are:
.Bl -enum -offset indent
.It
providing a hook for accessing host files via the
.Xr rump_etfs 3
interfaces.
.It
supporting enough of file and directory interfaces to facilitate simple
operations such as hosting config files or creating mount points.
.It
being small and lightweight so as to keep a barebones rump kernel
lightweight.
.El
.Pp
.Nm
is not intended for hosting large files or big directory
hierarchies.
If faced with such a use case, mounting a tmpfs file system
inside the rump kernel is recommended.
.Sh SEE ALSO
.Xr rump 3
.Sh HISTORY
.Nm
first appeared in
.Nx 6.0 .