This issue occurs if the VA Hostname/FQDN is defined in the system with UPPERCASE characters. The nodes information will not be displayed due to a case-sensitive validation.
Resolution
This is a known issue affecting VMware vRealize Automation 7.3.
This issue is resolved in VMware vRealize Automation 7.3.1 and VMware vRealize Automation 7.4, available at VMware Downloads.
To work around this issue, log in to vRA VAMI page with the appliance IP address instead of the FQDN/Hostname.
Additional Information
This behavior should not break anything else besides loading the cluster tab.
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