---
title: "Volumes in a Managed Kubernetes cluster"
sidebar_label: "Volumes"
sidebar_position: 1
description: "General information about volumes used in Managed Kubernetes clusters"
toc_max_heading_level: 2
---

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# Volumes in a Managed Kubernetes cluster

Managed Kubernetes uses [local](/cloud-servers/volumes/about-local-disks.mdx) and [network](/cloud-servers/volumes/about-network-volumes.mdx) disks from the cloud platform.

You can use local and network volumes in a Managed Kubernetes cluster as a [boot disk](#boot-volumes) and for [data storage](#storage-volumes).

When choosing a disk, consider the [specifics of using local and network volumes in Kubernetes](#using-network-volumes-and-local-disks-in-kubernetes).

## Using network volumes and local disks in Kubernetes \{#using-network-volumes-and-local-disks-in-kubernetes}

<CustomTable>
  <table data-sticky>
    <thead>
      <tr>
        <th />

        <th>Local disks</th><th>Network volumes</th>
      </tr>
    </thead>

    <tbody>
      <tr>
        <th>Advantages</th><td>Low data access latency</td><td>Ability to store persistent data that needs to be preserved during pod restarts and migrations</td>
      </tr>

      <tr>
        <th>Limitations</th><td>No data accessibility between pods</td><td>Additional network latency for data access</td>
      </tr>

      <tr>
        <th>Objects in Kubernetes</th>

        <td>
          Volume and VolumeMounts, <br /> PersistentVolumes and PersistentVolumeClaims (when installing the CSI driver manually)
        </td>

        <td>PersistentVolumes and PersistentVolumeClaims</td>
      </tr>

      <tr>
        <th>Usage</th>

        <td>
          <ul>
            <li>Boot volume</li><li>Data storage</li>
          </ul>
        </td>

        <td>
          <ul>
            <li>Boot volume</li><li>Data storage</li>
          </ul>
        </td>
      </tr>
    </tbody>
  </table>
</CustomTable>

## Boot volumes \{#boot-volumes}

Boot (system) volumes are used to start and initialize the operating system and applications in Kubernetes containers.

You can use [local](/cloud-servers/volumes/about-local-disks.mdx) or [network](/cloud-servers/volumes/about-network-volumes.mdx) disks from the cloud platform as boot disks. You can select the disk size for a network volume, whereas the size for a local disk is fixed.

You select the boot disk when creating a cluster and cannot change it after the cluster is created. When choosing, consider that:

* network volumes of the Universal SSD v2 and Fast SSD v2 types do not support changing the IOPS limit in a fault-tolerant multi-zonal cluster;
* in some fixed configurations with GPUs, only a local disk is available.

When nodes are reinstalled, all data on the boot disks is deleted.

Nodes are reinstalled during:

* when [updating a minor version](/managed-kubernetes/clusters/upgrade-version.mdx#update-minor-release) in a cluster on cloud servers;
* [reinstalling nodes manually](/managed-kubernetes/node-groups/reinstall-nodes.mdx#reinstall-nodes-manually);
* [auto-updating patch versions](/managed-kubernetes/clusters/upgrade-version.mdx#enable-patch-release-update) in a cluster on cloud servers;
* [auto-healing nodes](/managed-kubernetes/node-groups/reinstall-nodes.mdx#node-self-healing).

## Data storage volumes \{#storage-volumes}

To store data in Managed Kubernetes clusters, we recommend using [PersistentVolume](/managed-kubernetes/volumes/persistent-volumes.mdx) (PV) on network volumes.

If you have installed the CSI driver yourself and created a PV on a local disk, the data will be deleted when the node is removed.

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