OS X vnc server problems

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OS X vnc server problems

Hello,

I've got the following setup:

A Windows Desktop PC (my main PC) to which keyboard/mouse/displays,... are connected.

A Linux PC (7 years old), that is connected to the same network as my PC. There's no keyboard/mouse/display connected to the linux (only power and ethernet). I use this linux using RealVnc viewer on my PC (works like a charm, )

Now I have added a Mac Mini, which I would like to use the same way as the Linux. As OS X has a build in VNC server I thought this to be a piece of cake but I've run into some problems:

- Keyboard: I use a 'none standard' keyboard. I set up the Mac to use the keyboard without problems, when a keyboard was connected to it during initial setup. If I use Vnc viewer, the keyboard is a US style keyboard (I guess, but I can't say for sure as the flag at the top is still the correct one). This is a major issue.

- Speed: the Vnc to the Mac is significantly slower than to the Linux (this is annoying, and I like to have it improved but if necessary I can live with it ).

- Display size: as no display is connected the the Mac, it apparently assumes that it needs to be displayd in a 4:3 factor. I have two widescreen displays so if necessary I use one fullscreen for the Linux or the Mac (but on the Mac I have two unused areas at the sides). This is not really important but if I can have it fixed, why not.

There does not seem to be much settings about the vnc server I the Mac so anybody an Idea on how to solve this?

Using another Vnc Server is possible (but if possible with the internal one its even better).

Using another Vnc client is also possible (but again, if I can stick to the client I'm already using for years, I'd like that better).

Thanks in advance for any help

Mac mini, OS X Mavericks (10.9.3)

Posted on Aug 26, 2014 7:46 AM

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Answer 1

Loner T

Level 9

59,536 points

Aug 26, 2014 8:02 AM in response to Mini13579

Keyboard - You can define a virtual keyboard, or use some of the preferences in Accessibility -> Keyboard.

Speed - You should look at the Quality tab under Screen Sharing for performance changes.

Once you connect to the Mini, can you change the Display under System Preferences?

The client can specify -geometry and X11 keyboard mappings as well.

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Answer 2

Mini13579 Author

Level 1

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Aug 26, 2014 8:30 AM in response to Loner T

Hello Thanks for the response:

Keyboard: The accessibilty does not really help me and if you mean the "on screen keyboard" sorry that's not an option.

Mappings on the client: I can map some special keys like ctrl, alt and cmd but, for instance the Q and the A are switched on my keyboard comparded to the US keyboard and the client hasn't got an option to map these.

Speed: The quality tab? Is this in OS X or in the viewer (can't find it in OS X, I'm not running OS X server but appearently I've posted in a subcategory of severs)..

Display: Yes I can change the settings but only to the resolutions 1024x768 and 1280x1024 (a bit low these days...)

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Answer 3

Loner T

Level 9

59,536 points

Aug 26, 2014 10:36 AM in response to Mini13579

The XvncServer has a parameter called -RemapKeys which can help setup custom key mappings.

This is the Quality screen, which can help influence speed.

This is the Display screen, which can influence the screen.

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Answer 4

Aug 28, 2014 1:59 AM in response to Mini13579

If there is no monitor connected to the Mac or the monitor is turned off then the Mac will 'disable' the video card and emulate a basic lower spec video in software. This will be a 4:3 aspect ratio and a fixed lower resolution. It will also be much slower drawing the screen and this includes the speed of the VNC session because it is only running in software on the main CPU instead of in hardware on the GPU.

While it might be possible with other VNC software to override the resolution and aspect ratio the speed will still suffer as detailed above.

Apple's reasoning presumably is that if there is no monitor connected then what is the point in enabling the video card since it cannot be displayed.

In the olden days when dinosaurs roamed the earth 🙂 a trick used on headless systems was to make up a special VGA plug with a resistor across a couple of pins that did nothing but trick the computer in to thinking a monitor was still attached. While the same solution is no longer possible a slightly different and more expensive approach might be. The Gefen DVI Detective+ is a device that can 'learn' the settings of a particular monitor i.e. aspect ratio, resolution, refresh rate, and then even when that monitor is disconnected it can continue to 'send' those settings to the computer. The computer will then think the monitor is still connected, it will keep the video card enabled, and it will use it to generate a screen image matching that resolution and aspect ratio. Furthermore because the video card is still being used it is faster than the software emulation of a screen.

See http://www.gefen.com/kvm/ext-dvi-edidp.jsp?prod_id=4715

You could look on eBay for a secondhand one.

A KVM switch does a some what similar thing in that it sends a signal to each computer from the monitor.

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