After setting up a vSphere with Kubernetes Cluster, customers have the option of enabling a built-in private container registry that can be used with the Supervisor Cluster. This private container registry uses the popular Opensource Harbor solution which is also a Cloud Native Computing Foundation (CNCF) project.
Although this is a convenient capability, one thing to be aware of is that the embedded Harbor registry is limited in functionality compared to a standalone Harbor deployment and this is by design. When logging into Harbor with your vCenter SSO user, you will be able to do perform basic operations such as pushing and pulling images from this registry. For customers that require additional functionality from Harbor, it is recommended that you setup an external Harbor instance which can also be used as a common registry for both the Supervisor Cluster as well any Tanzu Kubernetes Grid (TKG) Clusters that you may provision.
With that said, I have heard from a few folks who were interested in accessing the Harbor UI using the "admin" account, mostly from an exploration standpoint. The admin credentials for Harbor are dynamically generated each time the service is enabled and it is stored as a K8s secret within the Supervisor Cluster. This means the admin password is unique for each environment and the instructions below will show you how to obtain the credentials.
UPDATE (12/16/20) – I was informed by Engineering the ability to read K8s secrets was actually a bug and this has since been fixed in the latest release of vSphere with Tanzu. If you need the harbor credentials, you will need to directly login to the Supervisor Cluster from the VCSA (instructions have been updated below) to retrieve this information.
Disclaimer: This is not officially supported by VMware and the behaviors described below could change in the future without notice.