Screen Sharing/VNC Stops Working

[super_kev]

Hi folks,
I have a headless Mac Mini running 10.11.6 with Plex for years, and in the past 6 months or so I've noticed that I can no longer use Screen Sharing or Remotix to log in - it just times out. Same with trying to connect via network/filesharing. If I plug in a keyboard/mouse and restart, I'm good for awhile, then it stops responding again after some time. Got any ideas as to what's going on? Running a Tomato router, haven't really had any changes there. I've turned off Screen Sharing and File Sharing, restarted, turned back on, restarted and still no change. It works for a bit (hours? days? don't know don't access it very often) then just stops and times out. Interesting thing is that I can still use Plex and access my iTunes shared library from this computer even though I can't connect to it.

 

[super_kev]

*bump*

 

[jtara]

Sounds to me like it’s not VNC and file sharing that is quitting - it’s your Mac Mini that’s quitting!

when you plug in the mouse/keyboard/screen, is is responsive? That is, before you reset?

My 2012 Mac Mini was occasionally freezing, at first every few days, and eventually hourly.

replaced heatsink paste, and the problem has not recurred.

 

[super_kev]

Nope, not freezing, still functioning just fine. I finally thought of port scanning last night after bumping this thread, and sure enough, port 5900 is not open on the Mac Mini in question even though it's enabled through system preferences... how can I reset this so that it works? Some network settings must have gotten corrupted...

 

[jeyf]

maybe one of the computers has a power save mode that is timing out?
research into looking at the headless system error log? see if it is shutting down w/a hardware error
get the ios free network app Fling. look at what is going on lan side of your router
i had an older mac mini burn up smoke.
sounds stupid; show the headLess mini some love, maybe take it off wifi and or new ethernet cable

 

[vixster1901]

I would toggle the remote button (under sharing). turn it off, reboot, turn it back on. let us know how it goes.

 

[jeyf]

restart the app, see if the 5900 port becomes open
maybe something else is controlling this port
again the ios app "Fling" is handy, it is an outside view of your network

 

[jtara]

Did you check Activity Monitor to see if there are any processes that aren’t responding?

 

[super_kev]

Ok, so it's fixed and I figured I'd post the solution in case others have a similar problem, I dug all around, and noticed right after restarting that port 5900 was open, but then closed. Hooked up a monitor to it, and low and behold something got corrupted during the restore open applications / windows part of the bootup after automatic login. The mouse would move around on the screen, but the Finder, iTunes, and other apps appeared frozen/unresponsive (yet I could still access their data from other computers). So, I made sure not to restore the windows upon reboot (clicked cancel, otherwise it'll automatically do it), and bingo, all is well. Filesharing and Screen Sharing work. So perhaps it was a "soft freeze" if there is such a thing? Weird.

 

[vixster1901]

estore open applications / windows part of the bootup after automatic login.

I hate that function. I tell all not to use it. When things start up on their own, it makes debugging much more difficult; such as in your case. I want to control what apps start up. Glad you got it working and thank you for sharing your fix.