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What is a Datastore in VMware?

 What is a Datastore in VMware?


A datastore in VMware is a logical storage container used by ESXi hosts to store and manage files related to virtual machines (VMs) and other components. It abstracts the physical storage devices and presents a uniform storage interface in the vSphere environment.

Think of a datastore like a shared folder or hard drive where all VM-related files are kept — regardless of whether the underlying storage is local, SAN, or NAS.

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🗂️ Common Files Stored in a Datastore

Here are the main types of files you’ll find in a VMware datastore:

File Extension Description Purpose

.vmdk Virtual Disk File Contains the VM's data – like a virtual hard drive
.vmx VM Configuration File Contains settings (CPU, RAM, devices) for the VM
.nvram BIOS/UEFI Settings File Saves the state of the virtual firmware
.log Log File Records VM operations for troubleshooting
.vmem VM Memory File Stores the VM's memory during suspend or snapshot
.vswp Swap File Used when the VM runs out of allocated RAM
.vmsd Snapshot Metadata Tracks information about snapshots
.vmsn Snapshot State File Saves the state of VM at snapshot time (RAM + device state)
.iso ISO Image File Disk image of OS installers or tools
.flp Floppy Image File (Legacy) Floppy disk image used for boot tools or drivers
.rbs, .dmp, .ctk Various backup, crash dump, and change tracking files

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📁 Examples of What’s Stored in a Datastore

1. Virtual Machines

.vmx (config), .vmdk (disks), .nvram, .log, .vswp, etc.

2. Snapshots

.vmsn, .vmsd, delta .vmdk files

3. Templates & ISO Images

OS installers, VMware Tools ISOs

4. Scripts and Other Files

Custom scripts, backups, exported OVF/OVA files

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🔧 How a Datastore is Used

Deploy VMs from templates or ISOs

Store VM data persistently

Backup/restore operations

Snapshot storage

vMotion and shared VM access across hosts (for shared datastores)



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