---
title: "Mount an SFS on an instance"
description: "Mount a TIR Shared File System on an instance from the SFS's own screen, so the instance can read and write its data."
content_type: "how-to"
product: "tir-sfs"
platform: "TIR"
url: "/tir/tir-sfs/how-to/mount-an-sfs-on-an-instance/"
topic: ["create-and-connect"]
---

# Mount an SFS on an instance

Mount an SFS on an instance, so the instance can read and write the SFS's data at a mount path you choose.
You can mount it from the SFS's screen, as these steps do, or from the instance's **Shared File-System**
tab; for the instance side, see
[Mount datasets and file systems on an instance](/tir/tir-instance/how-to/mount-datasets-and-file-systems/).

## Before you begin

- An SFS, created and ready; see [Create an SFS](/tir/tir-sfs/how-to/create-an-sfs/).
- An instance in the same project and region. You can also create one as part of this task.
- Your work on the instance saved to `/home/jovyan`. Mounting restarts a running instance, which
  ends every process in it and clears everything outside the workspace and mounted storage.

## Open the SFS's Instances tab

In TIR, open your project. In the side menu, under **Storage**, select **Shared File System**,
then select the row of the SFS you want to mount, and open its **Instances** tab.

## Mount the SFS

To mount it on a new instance, select **Create Instance** on this tab. It opens the instance
create form with this SFS already chosen for you. See
[Create an instance](/tir/tir-instance/how-to/create-an-instance/) for the rest of that form.

To mount on an existing instance:

1. In the instance's row, type a mount path, such as `/home/jovyan/shared`. A path inside the
   workspace shows the SFS in JupyterLab's file browser. For the mount path rules and the refused
   paths, see
   [Mount datasets and file systems on an instance](/tir/tir-instance/how-to/mount-datasets-and-file-systems/#mount-path-rules).
2. Select **Mount**.
3. Mounting restarts a running instance, and packages you installed by hand will need reinstalling.
   In the **Mounting File-System** dialog, tick the box, then select **Continue**.

Expect the restart to take two to three minutes.

## Check the mount

Once the instance is **Running** again, its row shows **Mount Status** as **Mounted**, with the
mount path you set. From a terminal in JupyterLab or over SSH on the instance, list the path:

```bash
ls /home/jovyan/shared
```

Replace the path with the one you mounted. Files on the SFS follow ordinary Linux permissions: any
user on the instance can read and write wherever the file and folder permissions allow it.

## Unmount the SFS

Select **Unmount** in the instance's row, tick the box, and select **Continue**. Unmounting restarts a running instance too. The data stays on
the SFS; only the mount on this instance is removed, and you can mount it again later.

Any other instance or training job that mounts the same SFS reads and writes the same files. If the mount is refused, see
[Troubleshooting TIR Shared File System](/tir/tir-sfs/troubleshooting/tir-sfs/).