Thunderbolt won't wake from sleep on Mac Mini Server w/Lion 10.7.1

Question

I have done the firmware updates, thought the probelm was fixed, but again, the display was asleep (as far as I could tell) and would not wake up.......unplugging and replugging the TB cable made it come right back.
TB display : Firmware Version:          22.2
Mac mini:
  Vendor Name:          Apple, Inc.
  Device Name:          Mac mini
  UID:          0x0001000C1064CB00
  Firmware Version:          22.2
  Port:
  Status:          Connected
  Link Status:          2
  Port Micro Firmware Version:          2.0.7
  Cable Micro Firmware Version:          0.1.18
Thunderbolt Display:
  Vendor Name:          Apple, Inc.
  Device Name:          Thunderbolt Display
  Vendor ID:          0x1
  Device ID:          0x8002
  Device Revision:          0x1
  UID:          0x00010001001E12A0
  Firmware Version:          22.2
  Port:
  Status:          Connected
  Link Status:          2
  Port Micro Firmware Version:          0.0.21
  Cable Micro Firmware Version:          0.1.18
  Port:
  Status:          No devices connected
  Link Status:          7
  Super Port Micro Firmware Version:          0.0.21

Answer 1

Hi John,
Thanks for starting this thread!   This has happened to me about four times thus far.
I've exactly the same setup as you (Lion Server on a 2011 Mac Mini with SSD and TB display), except a Pegasus RAID is also connected.  While I've configured the display to sleep, this has happened once even after leaving the mac for only about 30 seconds.  Turned back around and the display was black.
For now, I'm using a VNC client on an iPad (Jump) to VNC to the mini to restart cleanly.
A support document in Apple's display support section suggests zapping the PRAM so I'm going to give that a shot this evening when I get home (not very hopeful though...).
One other thing I might try would be to open Display Prefs via VNC and e.g. change resolutions, or click Detect Displays, etc.  Perhaps that will prompt the mini to reestablish sync with the display?  We'll see...
Again, thanks for this thread.  At least I know I'm not alone...