HCX vSphere Web Client plug-in will not load in vCenter UI post 8.0 upgrade.
Impression:
This may happen in two possible scenarios:
HCX plugin is now supported as a remote plugin from vCenter 8.0.0 onwards and if user is unable to resolve secondary hostname used for vCenter plugin isolation that is "vcenter-plugins.####.com" in that case the HCX plugin UI does not load from the browser.
Note: Starting from vCenter 8.0.0, vSphere Client Local plugins are deprecated. Refer to local plug-ins are being deprecated with the 8.0 release.
We have also identified that the "index.html" page for HCX plugin could be opened in a new browser tab but it could not be loaded in the plugin "Iframe" hosted in the vSphere UI page.
In this case, the vSphere UI content is loaded from "https://vcenter.####.com/" whereas the HCX "index.html" page is loaded from "https://vcenter-plugins.####.com/", which prevents the browser from displaying the HCX plugin "Iframe" content inside the vSphere UI.
Fixed in HCX 4.6.1 release.
For case 2 only: You can open a Service Request with VMware Global Support Services and include the required information to work on remediation if running HCX 4.5.0.
Alternatively, you are also recommended to view the HCX dashboard using HCX hybridity Standalone(443) UI for all versions and continue with the operations.