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Despite the fact that ploop is not a file system, a trick exist

to make it look and feel like so — i.e. to use usual <code>mount</code>

This article describes how it works and can be used.

ploop is not a filesystem per se, but a kernel [[w:loop device]] driver, providing a way

to represent a ploop image (or a set of stacked images) as a

container.

Therefore a complete ploop mount consists of two steps:

# "mount" ploop image(s) to create a ploop device (/dev/ploopNNNNN)

# mount a filesystem residing on this ploop device to a mount point

For simplicity, these two are usually wrapped to be done together in one step (say when you use ploop mount with -m option).

In reality, step 1 is kernel assembling a device out of image(s), and step 2 is the real mount.

You can use the following syntax to mount a ploop device and the filesystem inside it:

The following options are supported:

<code>-r</code>, <code>-o ro</code>

: mount read-only

<code>-v</code>, <code>--verbose</code>

: be more verbose

<code>-f</code>, <code>--fake</code>

: do everything except for the actual mount

<code>-n</code>, <code>--no-mtab</code>, <code>-s</code>

: these options are deliberately ignored

To unmount, DiskDescriptor can be specified:

A mount point can be used as well:

Note that umount can only work if:

# /etc/mtab is a separate file (not a symlink to /proc/mounts);

# mounting was done using <code>mount</code> (not <code>ploop mount</code>).

Otherwise, umount binary will not be able to find <code>ploop</code> as the "filesystem"

field in /etc/mtab, and will not call <code>umount.ploop</code> helper. As a result,

file system will be unmounted, but ploop device itself will stay mounted.

<code>ploop mount</code> and <code>ploop umount</code> commands,

as described in {{Man|ploop|8}} man page.

* [[Ploop]]

* {{Bug|2817}}

[[Category: Storage]]