The query service is not available or was restarted. Please retry.
Of course retrying doesn't work. Hardware status worked fine for all hosts in my protected site. I thought maybe it was a problem with linked mode in vCenter so I logged on to the vCenter server in the recovery site, fired up the vSphere client, opened the Hardware Status tab and got the same results.
I then started another instance of the vSphere client and logged directly on to the ESXi host. The hardware sensor data worked fine here (it's not in a separate hardware tab, but looks nearly the same). Hmmm.... must be something with vCenter?
I Googled the error and found this VMware KB:
Well it's the exact same error message so this must be the fix, right? Wrong!
First of all, step 14 is incomplete. Please follow these steps to reset the vCenter Inventory database:
Secondly, this was not the only problem and probably didn't ultimately fix the issue. I found this link in the same Google search:
The above forum posting had a link to the following web site with instructions on updating the ADAM instance vSphere uses for linked mode:
While this was for 4.1, the same settings apply to 5.0. The only thing I would recommend is checking all of the common name (CN) properties to make sure the FQDNs are correct. You do not need to change these to IP addresses!
I did have to reboot the vCenter server in the recovery site after making the changes. Even then, it didn't seem to start working until the following morning so it may take some time for the changes to propagate. Not certain about that but now the hardware status tab works for all servers in the recovery site.