Mac Pro sleeps after being woken up by WOL

Question

Hi Folks
In order to wake up my Mac Pro on demand, I have set up Wake Over LAN (WOL) over the network and enabled "wake for network access" at System Preferences > Energy Saver on the Mac Pro. Now I am able to wake up the machine from my local router or across the Internet, but just wake up for a little while only.
The issue is, after the Mac Pro is being woken up by WOL for about 30 seconds, the machine always goes into sleep mode again for no reason. During the short alive period, the virtual machines running on the Mac Pro are pingable   but the monitors are not on and the replaying YouTube video has no audio.
However, if I click the mouse or press the keyboard, the Mac Pro can be woken up as expected: the monitors are powered on, YouTube video is audible, all VMs are pingable too.
Why does my Mac Pro get woken up this way? How to fix it?
Thanks heaps in advance.
Regards,
B

Answer 1

> Now I am able to wake up the machine from my local router or across the Internet, but just wake up for a little while only.
From my local router, I use below way to wake up the Mac Pro.
I can also wake up the Mac this way over the Internet.
For your information, I can successfully wake up other WOL enabled Windows machines this way on the same network with no problem.
As mentioned, both ways can only wake up the Mac Pro for about 30 seconds, then machine will automatically sleep again though at System Preferences I have set the computer to sleep after "3 hrs" or "never", as shown below.
What I expect is just to make the Mac Pro back to work the same way like I locally press the keyboard or click the mouse, not to automatically sleep again in seconds.
Any thought please? Thanks!
R C-R wrote:
bengmugenr wrote:
The behavior is normal when clicking the mouse or pressing the key to wake the Mac, the issue only occurs when trying to wake via WOL. Never thought the same wake process could have different results.
Please explain specifically how you are trying to WOL, what you want to accomplish by doing so, & how long you think whatever it is you want to accomplish should take.
Also, what VM's are you running & by what method do they run (like via Parallels or whatever).