Virtual machines hosts are similar to physical machines which are hosted on ESXi Host (like a data in software). Wait, does this mean can the data i mean the Host recoverable in any case? The answer would be NO, If we delete the VM from the disk the resource files are also deleted but if we just delete from inventory, the data still exist and can be recovered as VM.

Snapshots are image of instances at that particular point of time. Can be considered as full backup of resource. we can restore to any snapshot at any point of time, with out any difficulties.

In this lab. we observer the difference between the deletion from Inventory and disk and then create different snapshots and restore at different intervals.

Task1: Unregister a virtual machine from a VCenter Appliance Inventory

Step1:VMs and Templates>VM2-3 >DataStores tab and check the storage: Shared-ISCSI-VMFS

Step2: Power off and click remove from inventory

Step3: Confirm for removal

Step4: Navigate to datastore and verify the VM

Does folder name VM2-3 exist?

Since the hot-clone VM is renamed as VM2-3 the datastore will always be with default first name which is hotclone

Task2: Register a virtual machine in the vcenter server Appliance Inventory

Step1: Click Hotclone.vmx file in datastore and rightclick to register VM

Step2: Select the Name and location to store the VM

Step3: Select ESXi1 and with default options finish

Step4: verify the VM2-3 created in LABVMs folder

Task3:Unregister and delete Virtual Machine from the Datastore

Step1: Select VM-FromLab and click delete from the disk

Step2: Verify in the datastore whether the datafiles are deleted or not

Task4: Take Snapshots of a virtual machine

Step1: Login to VM1-2 machine and drag IOMeter to recyclebin

Step2: Rightclick and select empty recycle bin

Step3: Take Snapshot by right clicking on VM and snapshots> takesnapshot

Step4:Name snapshot as “without IOMeter”

Step5:Login to VM1-2 and drag the CPUBusy file to recycle bin

Step6:Rightclick and empty recycle bin

Step7: Rightclick the VM and click Take Snapshot

Step8: Name it as Without IOMeter and CPUBusy

Step9:Select the Class-Vsphere ISO in the CD Drive from NFS DATaStore

Step10: Click on expand CD/DVD and Select Datastore ISO FIle

Step11: Open CD Drive in VM1-2

Step12: Drag CPUBusy to Desktop

Step13: Select Snapshots >Take Snapshot

Step14: Save it as withCPUBusy and description as added CPUBUsy

Step15:Click on Manage Snapshots

Step16: To Revert follow next step

Task5:Revert to Virtualmachine to a snapshot

Step1: Select All actions>revert to

Did the Virtual Machine power off and why? Yes since the memory state was not preserved .

Step2:Verify wheter ISO Meter and CPUBusy is on desktop? It wont be there since the snapshot we redirected to doesn’t have them .

Step3:Click on all actions revert to and select with cpubusy

Did the virtual machine poweroff and what is the reason? No Since it has preserved memory state .

Step4: Login to Console and verify whether CPU Busy is on desktop

IS CPUBusy on the desktop? – Yes it is since the old snapshot has

Is IOMeter on the desktop?No

Task6: Delete an individual Snapshot

Step1: Select VM>Actions>Manage snapshots

Step2: Select withoutIOMeter and CPUBusy and click on delete snapshot in actions

Did the virtual machine poweroff? No, it didn’t since it doesn’t have any effect on VM.

In the virtual machine console , is the CPU Busy file on the desktop? yes, since deleting snapshot will not effect the state of VM. It only removes an option to point back to that particular point of time.

Step3: Confirm deletion

Task7: Delete all Snapshots

Step1: Rightclick VM1-2 >Snapshots>Delete all Snapshots

Step2:Confirm by clicking yes.

Were all the remaining snapshots deleted from the tab? Yes they are all grouped and removed from the system

Step3: Login to console and verify whether CPU Busy is on Desktop

Is CPUBusy on the desktop, and why? Yes, Since there are no changes made to machine after the reversion.

Troubleshooting: This was direct lab, with simple clicks . Since we are handling a nested VM Situation, uploading data inside the VM had issues, we need to upload the data in to local datastore ,then ESXi and by setting the VM host CD/DVD as Host device, we are able to upload the documents.

Critical Thinking: Snapshots consume lots of data ,however they are best available options for full restore of instances. While building an architecture by setting milestones and taking snapshots help to reduce redoing of things.

Apart from this, in a business scenario, before new changes are added to system, snapshot is preferred, since we can restore and resume the applications without any issues ,thus helps to maintain VM environment healthy.

Naming convention should be highly considered and maintained , since the updation of VM name is not possible on disks, recovering from the disk at later stages would be confusing and annoying. A subversioning tool must be maintained with the names of the VM’s to avoid such issues.