I experienced this issue while working on a particular platform. It was a weird one so thought I would document it.
Trying to remote console to a VM using the vRealize Automation (vRA) portal would fail with the message…
Cannot establish a remote console connection , verify that the machine is powered on if the server has self-signed certificate, you might need to accept certificate, then close and retry the connection.
I found this weird as it was not an issue in any of my lab environments running on the same version. Neither was it an issue on my existing vRealize Automation (vRA) 6.x in the same environment. It appears to affect any vRealize Automation (vRA) 7.x version.
I had taken multiple steps to diagnose, including putting everything on the same vlan as the vSphere hosts (bypassing firewalls & load balancers etc) but no matter what I did the issue remained.
The fix was an undocumented timeout setting provided by the VMware engineering team. The default timeout setting is 10 secs (10000 ms).
/etc/vcac/security.properties file on the vRealize Automation appliance(s).
Add the below line to the end of the file and save.
Then restart the vcac service:
service vcac-server start