Symptoms:

• You increased the size of a datastore in the past, but now when you open vCenter, you see the old (smaller) size displayed.  There may be low disk space warnings.
• Web client for vCenter 6.5  and vSphere 6.5  and probably vCenter 6.0 and vSphere 6.0
• If you refresh the datastore information, the correct size displays and the warnings go away temporarily.
• The problem re-occurs.

Root Cause

According to the VMWare forums, this is caused by having different ESXi versions on the hosts in the datacenter.    Such as one host has Update 1 and another host has Update 3.    The recommended fix is to simply update all ESXi to the same version.

What happens if you can’t?

In my case, I needed to use a custom HP image for some servers, and I’m not going to take down the other hosts to install that custom image.   So I kept trying things and found a good workaround.

Workaround

For EACH host in the datacenter that had a connection to the faulty storage, I performed these steps:

1. 1. Navigate to Hosts & Clusters tab
   2. Select first host

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