I have seen this issue now multiple times especially in vCenter 6.0 setup of enhanced linked mode, and thus sharing the solution implemented in the scenario.
Issue : Two sites , let’s say DC and DR. Each site having it’s own vCenter appliance with an External Platform Services Controller . The PSC are part of the Single SSO domain in two different sites and hence forming an Enhanced linked mode configuration.
Now, everything works fine, but as we know till vSphere 6.0 update manager is still installed on a separate windows machine and is linked to the vCenter. The same was done at each site where independent Update manager was deployed and connected to it’s respective vCenter at DC and DR. However, after this once we login to the web-client > Click update manager we are not able to see the update manager plugin from DR vCenter and also unable to manage the DR update manager from DC site.
After exploring the configurations for update manager/web-client on both vCenter’s at DC and DR, it was found that there is a permission issue on vSphere-client folder at DR site along with missing plugin files.
Working vCenter at DC :
Under the directory : etc/vmware/vsphere-client/vc-packages/vsphere-client-serenity# ls -lh
drwx—— 3 vsphere-client users 4.0K Oct 11 17:12 com.vmware.vcIntegrity-18.104.22.168963
Non Working vCenter at DR:
There was no directory as vc-packages under /etc/vmware/vsphere-client. Hence created the directory and copied the same file from DC vCenter.
Under the directory : /etc/vmware/vsphere-client/vc-packages/vsphere-client-serenity# ls -lh
drwx—— 3 root root 4.0K Oct 11 11:40 com.vmware.vcIntegrity-22.214.171.124963
But if you look closely, the permissions are owned by root and not vsphere-client users . Thus , used the below commands to modify the permissions.
chown vsphere-client /etct/vmware/vsphere-client
The above command also changes the owner to the underlying directories and files from root to vsphere-client
chgrp -r users /etct/vmware/vsphere-client
Now , when we check the same location /etc/vmware/vsphere-client/vc-packages/vsphere-client-serenity . It shows the same plugin and permissions as the working vCenter at DC.
Next step for the changes to take affect was to restart the vSphere-client service on the appliance , and relogin to the web-client and validate.
As we did, we are able to manage the update manager configuration from web-client at both sites now.
Thanks, hope this helps !!