No. I do have it set-up as a server, and both the system and disks are set to never sleep. (Energy Preferences).
And it is also set for "Wake for network access" -- which "theoretically" should wake it up on the Share Screen request, even though that option is, to the best of my knowledge, only meaningful for Ethernet connectivity. (Wake-on-Lan -- WOL).
I suspect that the NIC in the Mini is set to recognize WOL only from ethernet, but do not know.
Apple instituted WOL for Airport/Wifi some time ago, not on a later OSX right now to find that setting, but...
Oh yeah, Wake on Wifi requires an Apple Router...
Additionally, newer Mac’s have the ability to use their built in Airport Express cards to receive magic packets while they sleep. To see whether your system supports the service, navigate to system information and check under Wi-fi tab for “Wake on Wireless” support (Apparently WOL via Wifi only functions with networks using the Apple Airport Extreme router).
Looks like half of the issue is answered... The WiFi in the mini DOES support WOL, as does the iMac.
However, the basic problem still remains --
The Mini is NOT sleeping, but actively running as a server 24x7 -- web and mail (I run my own domain) -- and I can log in to the mini via ssh -- but it is NOT visible as a shared device in the Finder on the iMac, and I cannot use screen sharing. Since the mini has neither keyboard nor monitor, I have to remotely reboot it via ssh - i.e. "shutdown -r" to get it to re-appear so I can screen share.
The timing is an isue. This "disappearence" seems to happen infrequently and irregularly, but has happened twice since I acququired the Mini on "Black Friday," not quite 30 days ago. If it were a simple "sleep" issue, I would have expected it to happen "hourly" or on some such frequency.
So, since WOL does not appear to be an issue in and of itself, I suspect I'll have to try to find out if "Shared Screen" is an "Advertised Service" via BSP.
Your link to http://superuser.com/questions/306651/wake-macbook-on-wi-fi-without-airport-extr eme is providing a lot of pointers. Now to spend some serious "Google time."
Since I'm working with the Verizon/ActionTec MI424WR-GEN3I router (FIOS), which seems to handle all of the various protocols without issue, I may have to dig out my old Airport Extreme.
Now retired, I sold my old 4 story Victorian and moved into a one-floor one-bedroom, and don't need the multiple routers I used to run to inorder for WIFI to cover the house. Sigh.
And to think "I thought" I retired from the world of System Administration
I have a query in to ActionTec to see if they have a configuation Option I have not "deciphered" which will deal with the WOW issue.
Got a response from ActionTec --
The router should support all of the WOW and WOL actions. No known issues.
However, it seems that Verizon just updated the router firmware about 2 weeks ago. (344 hours prior to my query, to be exact.)
In particular, that would have resulted in a "wipe" of "all router tables" maintained in the router; requiring the source of things like WOW to re-identify themselves to the router. (Both sides -- the iMac and the Mini.) The router is simply passive in those protocols.
So, I'll keep an eye on things and see if it happens again. That firmware update/reboot might have been the entire issue. At least this time, I know to check the "router uptime" parmeter.
Sigh, guess I'll dust off "MisterHouse" (sourceforge.com) and dig out the ActionTec monitor perl script.