Discovering the Names of ‘Unknown’ VMs

If you have had any issues with storage failing then you may have seen this issue – the virtual machines appear in vSphere as being ‘Unknown‘ and ‘(inaccessible)‘, as seen in the image.

Usually if the storage comes back up and the host has the storage rescanned then these will revert back to their correct name and the everything is fine again.

In some circumstances, though, they don’t come back up correctly in vCenter and they appear in the same format when connecting directly to the host… you may have your management team breathing down your neck wanting you to get it fixed as soon as possible and you think ‘I’ll recover them from a backup’ – if only you knew the name of the virtual machines!!!

unknownHopefully the following information will assist with going through and discovering the names of the virtual machines…

  • Even when a VM is in an ‘Unknown‘ state in vCenter, it is still registered against a host… if you switch to ‘Hosts & Clusters’ view and then click on ‘Virtual Machines’, you will see the ‘Unknown’ VMs listed and also what host they reside on – this will be the host that you get an inventory from
  • Next you should utilise WinSCP or something similar to connect to the host discovered earlier.
  • Once connected you should download a copy of the vmInventory.xml file from the following location: /etc/vmware/hostd
  • With this file downloaded, I would open it in Wordpad (to keep the correct formatting) and adjust the size of the text ( you may wish to print this out to work through and it is likely to run across multiple pages)
  • Print out the document, this will now become your reference for the virtual machines
  • Go back to the vCenter client, utilising the same view from earlier (you may wish to order the virtual machines by name to make the next task easier) – this should still be performed at the ‘Cluster’ level, as the virtual machines may have been vMotioned to other hosts since the ‘Unknown’ status occurred
  • For each entry on your document, see if you can find the corresponding virtual machine – I tend to go through and tick them if they exist and star them if they do not exist (just to make it easier to reference later)
  • After plowing through all of the VMs listed on the document, you should have a list of virtual machines that still exist ticked on your sheet and the virtual machines that are in the ‘Unknown’ state starred.
  • You can now use this information to perform a restore as required, the ‘Unknown’ virtual machines can be removed from the inventory by right mouse clicking on them and selecting ‘Remove from Inventory’

About the Author


I have been in IT for the past 15 years and using virtualisation technologies for around the past 8 years. I started, as quite a lot of people do, working with PCs after playing with such iconic systems like the ZX81, ZX Spectrum and then progressing through 386s, 486s, Pentiums etc. After being headhunted at sixth form to work for a small company based around Hertfordshire, UK. I began working with small businesses and gaining a lot of hardware experience. Three years later, after helping to increase the size of the business, I needed to gain exposure to a larger environment to progress my own career. I joined a large manufacturing company around Electronic Test and Measurement which progressed my skills onto more PC work, hardware work and then onto Server Operating Systems. I progressed again onto a consultancy company based in Reading, UK. Initially working as an engineer performing hardware / software installations for larger companies contracted out to the consultancy company, I moved up into a Consultant position continuing my travel across the UK assisting and providing solutions to companies. I finally moved on again to my current position, working back in Hertfordshire, UK. Again working for a large manufacturing company, this time with over 50,000 users worldwide. I am responsible for the datacenter hardware, the storage environment, the vmware environment and also implementing their new Citrix XenApp farm. My days are busy but also productive, its a friendly environment and in my four years of being with the company, I have seen many changes in technology and infrastructure in use within the company. About the site I started this site as I had been thinking of having more of a presence on the web for a while. On a daily basis, I perform tasks and use tools that others may not use or may not think to do and therefore I thought that I would share some of these experiences and tips with others to help with their day to day work. Currently, my main focus of work is around VMware and Veeam Backup & Replication but hopefully as my tasks progress, I’ll be able to share useful bits of information about other areas of IT as well.

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