---
title: Block Storage FAQ
description: Explore Scaleway Block Storage with our comprehensive FAQ covering performance, persistence, and more. Learn how Block Storage compares to Local Storage and its compatibility with Scaleway resources.
dates:
  validation: 2025-09-17
productIcon: BlockStorageProductIcon
---

import BlockStorageVolumeTypes from '@macros/block-storage/block-storage-volume-types.mdx'

## Overview

### Why should I use Block Storage instead of Local Storage?

The size of Local Storage depends on your Instance type. With today's configurations, the maximum Local Storage available is 600 GB.

Block Storage allows you to create bigger volumes and those volumes are persistent which means that they can live without being attached to an Instance.

|                    |         **Block Storage**         |           **Local Storage**                                                                                    |
|--------------------|:---------------------------------:|:--------------------------------------------------------------------------------------------------------------:|
| **Availability**   | High                              | HV dependant (needs physical intervention to retrieve storage and data if HV dies)                             |
| **Redundancy**     | High (replica 3)                  | Low (RAID 5 - 5 disks)                                                                                         |
| **Persistency**    | Yes                               | Semi-persistent (a snapshot of the volume is uploaded and downloaded each time the Instance is powered off/on) |
| **Latency**        | Average                           | Local NVMe                                                                                                     |
| **Volume size**    | Max 15 TB/volume                  | Up to 600 GB (GP1-XL)                                                                                          |


## Specifications

### What is the difference between Block Storage volume types?

<BlockStorageVolumeTypes />

You can attach a maximum of 16 volumes (including the mandatory boot volume) to a single Instance.

<Message type="tip">
  Refer to the [dedicated documentation](/block-storage/reference-content/differences-between-5kiops-volumes/) for more information on the differences between Block Storage 5K legacy volumes and Block Storage 5K volumes.
</Message>

### What level of performance is expected from a block volume?

Block Storage offers 5,000 input/output operations per second (IOPS) through powerful SSDs.
However, this is subject to fluctuation during peak load periods.

### What is the behavior of the block volume when an Instance is stopped, deleted, or crashed?

A block volume is persistent which means that it can live without being attached to an Instance. Nevertheless, when an Instance is deleted, the following can be expected:

- When the Instance is deleted via the Scaleway console, you will be asked if you want the distant block volumes to be deleted as well or not.
- When deleting an Instance via the `API`, all the attached volumes (local and Block Storage) are deleted. If you want to keep your local volumes, you must use the archive action instead of the terminate action.
- If you want to keep Block Storage volumes, you must detach them before you issue the terminate call.

## Quotas and limitations

### How many volumes can be attached?
A virtual Instance can bear up to 16 volumes, including the mandatory local volume.
Therefore, the maximum number of blocks that can be attached to an Instance is 15.

### What is the maximum size of a block volume?
The maximum size of a block volume is 15 TB.

## Pricing and billing

### How is the Block Storage fee calculated?
The Block Storage billing scheme is not the same as for Object Storage. You are billed by the hour based on the size of the volume and not the data that is actually stored on it. Just like a local drive, you can select the size of the volume directly from the Scaleway console or the API.

## Usage and management

### How can I convert a Block Storage legacy volume into a Block Storage volume?

Although there is no direct way to change the storage class of a volume while preserving its ID, you can still convert a Block Storage legacy volume (along with its data) into a Block Storage volume using the snapshot export/import features as a temporary solution. This allows you to transition a Block Storage legacy (`b_ssd`) snapshot into a Block Storage (`sbs_5k` or `sbs_15k`) snapshot and then turn the snapshot into a Block Storage volume.

    <Message type="important">
      The process below requires manual intervention and **does not preserve the original volume's ID**.
      While this approach allows you to transition to a Block Storage volume, it is only a workaround.
    </Message>

1. [Create a snapshot of your Block Storage legacy volume](/block-storage/how-to/create-a-snapshot/).
2. [Export the snapshot](/instances/api-cli/snapshot-import-export-feature/#exporting-snapshots).
3. [Import the snapshot into a new volume](https://www.scaleway.com/en/developers/api/block-storage/#path-snapshot-import-a-snapshot-from-a-scaleway-object-storage-bucket).

## Can I manage my Block Storage volumes using the Scaleway Instances API?

It is no longer possible to manage your Block Storage volumes using the Instances API.

## Compatibility and integration

### What other Scaleway resources are compatible with Block Storage?
Block Storage volumes are compatible with [Scaleway Instances](/instances/), [Managed Dabatase for PostgreSQL and MySQL](/managed-databases-for-postgresql-and-mysql/), and [Kubernetes](/kubernetes/) Kapsule clusters.