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In general I have seen such issues when there is a firewall or proxy preventing some of the data through - check that port 8010 (default and can be changed) is whitelisted (between hosts and vCenter and between vCenter and where you are accessing the GUI).
Check if same when not using https (-n switch)
Check if offline bundle generates correctly (-g switch and specify a different save location if don't want to use default)
Apologies, your question was in the topic header and I assumed it was web-access that was the issue.
Are you waiting until the run completes or using ctrl+C to end the session? Try the former and check that the file is of size.
Try opening the stats.html in another browser (with Admin rights) - I get the same in current Chrome but it works in Firefox.
Thanks Bob. It works with Firefox.
By the way, I waited until it finished writing the HTML bundle and i didn't interrupt the session.
Now the only problem is that, all the graphs have populated except the "VMs" tab. Neither "search" nor "Expand/Collapse all VMs" returns anything. Launching the stats.html in Firefox with Admin rights didn't make a difference either. I have to mention that this is the important part I was hoping I could have a deep insight. But unfortunately this doesn't work. I just don't know if it's by design or a bug with the offline bundle. How about in your system? Are you able to search a VM in this tab?
Experienced the same, firefox didn't help either.
Finally, worked with microsoft EDGE browser, except VM tab data all other graphs are visible.