--- title: Volumes layout: framework_docs objective: Local persistent storage for Fly machines. order: 3 --- If your application writes configuration, session, or user data to the file system and you want this data to persist across restarts you will need a [fly volume](/docs/volumes/). This doesn't apply if your data is stored in a database elsewhere (for example in PostgreSQL, MySQL, or MongoDB), but does apply if you are using Sqlite3. ## Creating a volume Use [fly volumes create](https://fly.io/docs/flyctl/volumes-create/) to create a volume. You can specify a region and a size (in gigabytes). Create one for each machine that you will be deploying as volumes can't be shared between machines. You will want to use the same volume name for each volume if these volumes will be mounted by separate instances of the same application. ## Mounting a volume When you created a volume, you gave it a name. Modify your `fly.toml` to contain a [mounts section](https://fly.io/docs/reference/configuration/#the-mounts-section) associating that source name with a destination file path: ```toml [mounts] source = "myapp_data" destination = "/data" processes= ["app"] ``` The `processes` section is optional if you only have one process defined in your toml. ## Accessing the volume Modify your application to read and write from subdirectories of the destination path you provided in your `fly.toml`. In the case of Sqlite3, set the `DATABASE_URL` value to include this path.

[mounts]
  source = "myapp_data"
  destination = "/data"
  processes= ["app"]