I have a Dell R720.
when energized the server. The button with the letter "i" that is in front stays on and does not go out more. Then the server does not turn on.
The energy comes from a UPS and is within normal parameters.
as I can I know that problem?
To confirm your issue is that your R720 not able to turn on althought power is supplied from the UPS right?
When the "i" is lid, there is a button on the "i", when you press it, does the LCD display any error?
Are you able to by pass UPS power to connect direct power to check?
Is this server working previously? Have you setup the iDRAC? Can you connect to the IP and check for the error message?
You might need to bring the server down into minimum POST components to verify the issue.
Unplug all power cables connected to the server, press and hold on the power button for 10 seconds.
Then remove the server components leaving only:
Try to turn on the server, if it powers up, then keep adding the components in while the server is off to check what is the root component issue.
Sorry for the late reply.
Did you manage to arrange any resolution to your service no POST?
If no, could you PM me your contact details, email and phone, I'll arrange someone to call or email you.