# Rootfs

![](https://trello-attachments.s3.amazonaws.com/5700ea0da7030dcf7485ed70/5a9941cae486d3ab50425859/d0a07eb7cdeaabc3350889bc176d705f/5.png)

A *roofs* provides ephemeral storage for your workload. It is ideal for content like buffers, caches, scratch data, and other temporary data.

*rootfs* is associated with container, instead of pod. Everyone container comes with its own dedicate rootfs. If a pod has only one container, there is only one rootfs in that pod; if a pod has four containers, there will be four rootfs in the pod.

*rootfs* use the `EXT4` filesystem. The size is fixed: 10GB.

## Lifecycle

There is no way to control rootfs, or view it in the web console. However, the following are some principles:

* *rootfs* is created and mounted automatically to the pod. You don't need to specify *rootofs* when you launch pods.
* *rootfs* is always mounted at the root path `/` in the container. There is no way to change that.
* You can't detach a rootfs from one pod and attach it to a different pod.
* The data in rootfs persists only during the lifetime of its associated pod. If the pod is restarted, data in the rootfs is reset.
* Currently there is no way to commit changes in a rootfs to a new Docker image.

## Billing

* A pod may have one or more containers.
* Every container come with a default 10GB rootfs, e.g. if a pod have 3 containers, the pod has three rootfs, 30GB in total.
* Rootfs exits along with the lifecycle of the pod. Billing begins when the pod is created, ends when the pod terminates or exists.
* The price is $0.0000000386/GB/second, and a default duration of 60 seconds is applied.