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---
title: Share a host directory with a guest using virtiofs
description:
published: true
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date: 2023-01-24T16:27:16.582Z
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tags:
editor: markdown
dateCreated: 2022-08-13T00:16:17.437Z
---
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# Sharing a directory
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> *As of January 2023, virtio-fs is only available for virtual machines managed by the system libvirt instance (`qemu:///system`)*
{.is-info}
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> *As of January 2023, virtio-fs does not feature a read-only mode. Do not share a host directory with a untrusted guest*.
{.is-warning}
[Virtio-fs ](https://virtio-fs.gitlab.io/ ), shorts for virtio shared filesystem, allows you to share a directory located on the host with a guest. It is designed to be fast and optimized for local usage, when the host and the guest are located on the same physical machine.
## The guest
### Edit XML configuration
* Memory backing needs to be added to the XML definition:
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```
< domain type = "kvm" >
[...]
< memoryBacking >
< source type = "memfb" / >
< access mode = "shared/>"
< / memoryBacking >
[...]
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< / domain >
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```
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* A filesystem device has to be added.
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```
< domain type = "kvm" >
[...]
< devices >
[...]
< filesystem type = "mount" accessmode = "passthrough" >
< driver type = "virtiofs" / >
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< source dir = "/mnt/" > # The host directory to be shared with the guest
< target dir = "share" / > # Contrary to what the name implies, this is the tag used inside the guest
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< / filesystem >
[...]
< / devices >
[...]
< / domain >
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```
### Mount the folder inside the guest
* Inside the guest VM, mount the folder using the following commmand to mount the `/mnt` host directory on the guest, using also the `/mnt` point:
`# mount -t virtiofs share /mnt/`
## Resources
* Official website: https://virtio-fs.gitlab.io/index.html#status
* In the context of a Windows guest: https://github.com/virtio-win/kvm-guest-drivers-windows/wiki/VirtIO-FS:-Shared-file-system