Sporadically slow web client on 6.7U3 - Two VMware support cases and 60+ days later no resolution

[cpetry7c1]

I've opened two support requests with VMware in the last 60-90 days.  I've rebuilt my VCSA per their recommendation.  I still have the same issue.

I have one VCSA that started to have web client slowdowns after upgrading from 6.7U1 to 6.7U3.  I do not have OpenManage installed on the hosts.  I've manually verified that OpenManage isn't installed on each host within this vCenter. 

Logging into the VCSA via SSO/Active Directory takes a very long time (2-5 mins).  Even with workaround https://kb.vmware.com/s/article/53698 applied. 

I need to reboot my VCSA every 2-5 days to restore performance. 

Once logged into the VCSA it doesn't always behave correctly - sporadically the UI slows down to the point where right clicking to bring up a context menu takes 2-5 minutes.  This occurs on any browser even when cache is cleared.

The ESXi hosts are running the latest build of ESXi on Dell PE R740xd's.

Occasionally, rebooting the VCSA will dis-join it from the domain (Windows 2003 functional level).  I know this functional level isn't supported and it's been difficult to get an answer as to whether this would cause these issues or not.

Any ideas?

[Nawals]

In vSphere 6.7 U3 Flash-based Web Client Deprecated. May be this could be the reason for slowness. Are you facing slowness using HTML?

Goodbye, vSphere Web Client! - VMware vSphere Blog

[cpetry7c1]

This happens in the HTML5 interface.

[daphnissov]

If you are clearly in an unsupported posture with respect to the AD functional level, and it sounds like your issues may revolve around authentication, why don't you do a test and disjoin it from AD and only use local OS authentication to see if your problems go away. If they do, logic would suggest you've found your culprit.

[cpetry7c1]

I've asked half a dozen VMware engineers about that "unsupported" AD environment and none of them can tell me if that'd cause this kind of issue.  They tell me all that means is they don't test it anymore.   I have other vCenters on this domain and I do not have this issue with them.

[cpetry7c1 · Accepted solution]

Well, it turns out it was Integrated Windows Authentication.  I switched our vCenters to use AD as an LDAP source and the problem went away.  I didn't know this but IWA is being deprecated and you shouldn't use it at all.

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