{{ $t('productDocDetail.updateTime') }}: 2025-12-31

A virtual datastore is either an ordinary datastore or a stretched datastore. The former is for standard HCI clusters, while the latter is for stretched HCI clusters.

You don't need to specify the number of replicas when initializing a virtual datastore, as it is determined based on the number of VMs. There are two-replica or three-replica modes.

To use a three-replica cluster with three or four hosts, you need to have at least three hosts per ordinary datastore and two disk groups per host. If your cluster has five or more hosts, there are no limits on the disk group.

A disk group can contain SSDs and HDDs or only SSDs. In the above figure, the host has two disk groups.

2.5.3.1Create Ordinary Datastore

Precautions

1. For large cluster projects, it is recommended to use multiple volumes. It is recommended that the number of nodes per volume be less than 12 and not more than 16 as far as possible. For example, 48 nodes in the cluster are recommended to be divided into four volumes and 12 nodes per volume.

2. Using RAID volumes to build virtual storage is not recommended because they generally do not support hot plugs. RAID should be configured as JBOD passthrough. If JBOD is not supported, disable RAID and use non-RAID.

Steps

1. Navigate to Storage > Virtual Storage, click New, and select the volume type as Ordinary datastore.

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2. Select the corresponding method and nodes to create a virtual datastore. Since we are creating the first virtual datastore, choose the Use disks on new hosts. You can enable RDMA for nodes as needed. For the introduction of the RDMA feature and the precautions for enabling RDMA, refer to Section 3.5.2 Enable RDMA (Optional).

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3. Select the hard disk to be added to the node. Configure hard disks and hard disk groups, and then make a detailed usage plan for each node's disk. The system will automatically detect the disks of all nodes in the cluster. By default, mechanical disks are selected as data disks and solid-state disks as cache disks. Using the default configuration is recommended. If you need to deploy multiple databases, you need to plan to reserve the disks of the second database group.

47. Select the disks that will be used to create a virtual datastore.
48. For a hybrid datastore, at least one SSD is required as a cache disk.
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4. Confirm the details and proceed.

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5. The following page displays virtual storage configurations, including available disk space, number of data copies, and the total number of disks. After confirming configurations, click OK. Then, input the administrator account password: admin. Then, click Finish to begin initializing virtual storage.
   2. Create Stretched Datastore

Steps

1. Configure the storage datastore type. Navigate to Storage > Virtual Storage and click New. Then, select the datastore type as Stretched datastore.

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2. Select the node. Select the nodes to be added to the stretched datastore. The stretched cluster requires at least 4 nodes.

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3. Specify fault domains. Add the required nodes to the corresponding fault domains. There are four nodes in this example, so two nodes are added to the Primary Fault Domain, while another two are added to the Secondary Fault Domain.

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4. Add Witness Node: Configure the witness node IP according to the pre-installed witness node after naming the Primary Fault Domain and the Secondary Fault Domain. Follow the wizard to enter the password to confirm the configuration of the witness node.

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59. After logging in to the witness node, you need to enable the SSH Port of the witness node under System > Port Management.
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5. Confirm the configuration: Confirm the configuration of the fault domain. Modifying the fault domain where the node is located after the datastore is created is not supported.

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6. Configure the Use of Disks. Next, you need to plan the use of disks, including data disk, cache disk, and spare disk. Generally, SSD is used as a cache disk to improve the IO performance of virtual storage. The system automatically recommends the type of hard disk according to the configuration. You can follow the default recommendations of the system.

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7. Confirm the configuration. Finally, the page displays the configuration result information of the virtual datastore, including the final storage capacity, the number of copies, and the number of disks. After confirming that the configuration is correct, you need to enter the administrator password and click OK to start initializing the virtual datastore.

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