IT Operations Management (ITOM)

How to reclaim your storage from unused VMs in 2 easy steps!

How to reclaim your storage from unused VMs in 2 easy steps!


Guest post by Vijay Ram S, 


Storage is lost in a lot of places and finding lost storage can get incredibly complex in large environments. More often than not, finding reclaimable storage takes significantly more time than performing the actual task of reclamation. However with the right set of information, we can figure out where we have reclaimable storage in a matter of seconds.


It is like having a map to the lost storage.


Thin Provisioning in the Servers

With the wide spread usage of thin provisioning in virtual servers, the task of finding lost storage gets a bit more complicated. For example if we find a powered off VM that is no longer needed, the question is how much storage would we get by deleting that VM? The answer is not as straight-forward as looking at the virtual disk sizes for the VM. If we need to do this across of thousands of VMs in the managed environment, we will end up feeling like Mario trying to find the princess in different castles.


Power of Inventory Workspace

HP Storage Operations Manager has an all-new Inventory workspace. This seemingly unassuming workspace is really powerful and offers information in different table views. Answers to everyday questions can be obtained from the inventory workspace in a matter of seconds by using the filter and sort functionality available in the table views.


Find Reclaimable Storage from Powered Off VMs

Storage Operations Manager makes it easy to find reclaimable storage. Begin your search by navigating to the Virtual Machines table view under Hosts group in Inventory workspace. Once in the table view, filter out powered off VMs by right clicking on the Powered Off value for Virtual Machine State field and selecting equals this value. See Figure 1.


Figure 1 – Virtual Machines view


Now that we have the list of powered off VMs, let’s look at the Size on Server (GiB) field. This field indicates the actual amount of storage consumed by this VM. It takes thin provisioning, snapshots etc. into consideration.  Click on the field (table view header) to sort by its value. A little arrow next to the field label indicates the sort order. See Figure 2.


Figure 2 – Finding the VMs with the largest storage consumption


Congratulations! We have just found the amount of storage that can be reclaimed from powered off VMs. Once we confirm which of these VMs can be deleted, we can precisely determine how much storage we can reclaim through this process.


The reclaimed storage can be used to create additional VMs at the server level or returned to the storage pool on the array by using the vSphere VAAI Thin Provisioning Block Space Reclamation (UNMAP) Primitive or a similar command.


Join us at HP Discover to learn more about Storage Operations Manager or visit the Storage Operations Manager product page to learn more.


About the author: Vijay Ram S, Software Designer, HP Software Storage Management


As a member of the HP Software Storage Management R&D Team, Vijay has nearly 9 years of experience developing software and solutions in the storage resource management domain - covering all facets of engineering and design, including development of HP Software’s next generation heterogeneous storage resource management platform, Storage Operations Manager.


Vijay has a Master’s Degree in Software Systems, from BITS Pilani, India


You can register for HP Discover, June 2-4 in Las Vegas here.


Michael Procopio Procopio
  • infrastructure management
About the Author


HPE Software Product Marketing. Over 20 years in network and systems management.