How to Create a VMware Datastore: Step-by-Step Guide (2025)…

Creating a VMware datastore means making storage available to ESXi hosts and virtualized workloads so virtual disks, ISO files, and infrastructure objects can be placed in a manageable location. The short answer is this: decide whether the datastore will be VMFS or NFS, prepare the correct local disk or network export, add the datastore through vSphere Client, and then validate that host and cluster visibility is consistent. This guide is written for administrators working in the August 25, 2025 context.

Quick Summary

Broadcom KB 409675 states that ESXi needs a boot disk of at least 128 GB to automatically create a local VMFS datastore during installation.
The same KB says that if a local VMFS datastore is required, you should either use a disk larger than 128 GB or present another disk and create the datastore afterward.
Broadcom KB 372207 explains that if the ESXi boot device is local storage and larger than 142 GB, the leftover space can be formatted and mounted as a VMFS datastore.
The same KB defines systemMediaSize values based on 32 GB, 64 GB, and 128 GB system storage footprints.
Broadcom KB 402096 shows that an NFS datastore mount can fail when the export path is missing the required leading slash (/).
Broadcom KB 323011 states that when multiple hosts mount the same NFS export, they must use the same IP address and the same mount path, or vCenter can show duplicate datastore entries.
In the August 25, 2025 context, Broadcom KB 326316 lists vCenter Server 8.0 Update 3g / 8.0.3.00600 / Build 24853646 as one visible current vCenter 8 baseline.

What Should Be Ready Before Creating a Datastore?

This guide is for teams defining new storage under a host or cluster in vCenter. The creation step itself is short, but incorrect datastore type choice or inconsistent mount standards usually creates bigger problems later.

Before you begin, answer these questions:

will this datastore come from local disk or network storage?
is the datastore intended for one host or multiple hosts?
will the storage be VMFS or NFS?
if it is NFS, will every host use the exact same export path and server IP?
if it is local VMFS, does the host storage design actually support it?

In branch, edge, or compact on-prem environments, the assumption that “ESXi installation automatically creates a usable datastore” is often wrong unless disk planning was done first.

Which vCenter Baseline Makes Sense for August 25, 2025?

Datastore operations are storage-centric, but their managed visibility still lives in vCenter. According to the build table in Broadcom KB 326316, one visible vCenter 8 baseline in the August 25, 2025 context is:

Product: vCenter Server 8.0 Update 3g
Version: 8.0.3.00600
Release date: 2025-07-29
Build: 24853646

This guide uses vCenter Server 8.0 Update 3g / Build 24853646 as the management baseline.

How Should You Choose Between VMFS and NFS?

In practical terms, datastore creation usually follows two main paths:

VMFS datastore
NFS datastore

VMFS is typically associated with local disk or block-based storage presentation. NFS relies on a network export path mounted by ESXi.

The most practical rule is:

use VMFS when the host is consuming a local or block-backed volume
use NFS when the host is mounting a file-based export from shared storage

The critical success factor is less about the name of the datastore type and more about following the exact rules of that type.

How to Create a VMware Datastore Step by Step

1. Choose the Datastore Type First

The first decision is whether this will be VMFS or NFS. That choice changes all later validation steps.

Clarify:

will the datastore be local or shared?
is the storage presented as disk capacity or exported as a file path?
is cluster-wide visibility required from the beginning?

2. Check Disk Size and Source for VMFS

Broadcom KB 409675 says that if a local VMFS datastore was not created during ESXi installation, the first thing to check is disk size. According to that KB, ESXi needs a boot disk of at least 128 GB to automatically create a local VMFS datastore.

Broadcom KB 372207 adds another important behavior:

if the ESXi boot device is local storage
and it is larger than 142 GB
the leftover space can be formatted with VMFS and mounted as a datastore

That means local datastore planning should be deliberate before installation, not discovered afterward.

3. Use `systemMediaSize` Intentionally When Needed

Broadcom KB 372207 explains that the ESXi installer boot option systemMediaSize can be used to limit system storage partition size. The supported values are:

min = 32 GB
small = 64 GB
default = 128 GB

This matters in compact system designs. But the same KB also says that a system with 1 TB of memory must use at least 64 GB for system storage, so the smallest option is not universally correct.

4. Create the VMFS Datastore

If the local or presented disk is ready, you can proceed with VMFS datastore creation. Broadcom KB 409675 recommends either installing on a disk larger than 128 GB or presenting another disk and creating the datastore separately if local VMFS is needed.

At this step, validate:

the correct disk or LUN is visible to the host
the boot disk is not being selected incorrectly
the datastore name follows standards
visibility expectations across the cluster are clear

5. Validate NFS Export Path Syntax Before Mounting

Broadcom KB 402096 shows a small but critical NFS mistake: if the export path does not start with the required leading slash (/), datastore mounting can fail even when network connectivity looks fine.

Before adding an NFS datastore, confirm:

the export path begins with /
the NFS server IP or hostname is correct
ESXi can reach the server
the expected ports are open

6. Mount the Same NFS Export Consistently Across Hosts

Broadcom KB 323011 states that if multiple hosts mount the same NFS share, they must use the same IP address and the same mount point.

That rule matters more than it seems. If different hosts mount the same export differently, vCenter can display duplicate datastore records for what is actually the same backend share.

7. Verify Visibility and Consistency After Creation

After the datastore is added, the work is not finished. Check:

is the datastore visible on the intended host or cluster?
do all required hosts see the same datastore?
are the name, path, and visibility consistent?
did any duplicate NFS entries appear?

A datastore that technically mounted but behaves inconsistently across hosts is not production-ready.

Most Common Datastore Errors and Fixes

ESXi installed but no local VMFS datastore was created

According to Broadcom KB 409675, the most common reason is that the boot disk did not meet the 128 GB requirement. The usual fix is to use a larger local disk or present another disk and create the datastore afterward.

NFS datastore cannot be mounted

Broadcom KB 402096 shows that one very common cause is a missing leading slash (/) at the beginning of the export path.

The same NFS datastore appears more than once

Broadcom KB 323011 explains that this often happens when the same export is mounted from different hosts using different IPs or different mount paths.

NFS datastore records cannot be cleaned up properly

Broadcom KB 323011 recommends removing the NFS share, re-adding it with the correct standard, and if needed restarting relevant vCenter services or ESXi management agents.

First 15-Minute Checklist

The datastore type was chosen correctly: VMFS or NFS
VMFS disk size and source were validated
The NFS export path was checked for the leading /
The same NFS share is mounted with the same IP and path on every host
The datastore is visible on the intended host or cluster
No duplicate datastore entry appeared
A basic test file or VM operation behaves as expected

Next Step with LeonX

After the datastore is created, the right next step is to define storage policy, backup behavior, performance monitoring, and host-cluster visibility standards together. That is how the datastore becomes operable rather than merely attached.

Related pages:

Frequently Asked Questions

Do you need external storage to create a VMware datastore?

No. Broadcom KB 409675 and 372207 show that a local VMFS datastore can exist when the disk design supports it.

Why was no datastore created automatically during ESXi installation?

The most common reason is disk size. Broadcom KB 409675 says that automatic local VMFS datastore creation requires at least 128 GB on the boot disk.

Why is the NFS path syntax so important?

Because Broadcom KB 402096 shows that leaving out the leading slash (/) can block the mount even when connectivity and ports look correct.

Why does the same NFS export show up as multiple datastores?

Broadcom KB 323011 says this can happen when the same export is mounted using different server IPs or different mount paths across hosts.

Why does `systemMediaSize` matter for datastore planning?

Because Broadcom KB 372207 explains that system storage reservation can be limited to 32 GB, 64 GB, or 128 GB, which directly affects how much local space remains available for VMFS use.

Conclusion

Creating a VMware datastore is not just attaching storage. It is about choosing the right storage model and then applying that model consistently. In the August 25, 2025 context, the safe approach is to validate disk sizing and system storage behavior for VMFS, enforce path and mount consistency for NFS, and verify visibility across all intended hosts before production use.

If you need help defining datastore standards, storage policy, or cluster-wide visibility design, you can contact LeonX.

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How to Create a VMware Datastore: Step-by-Step Guide (2025)

Quick Summary

Table of Contents

What Should Be Ready Before Creating a Datastore?

Which vCenter Baseline Makes Sense for August 25, 2025?

How Should You Choose Between VMFS and NFS?