Player.cfg is overwritten, changes are reverted

[nfitzkee]

Hi!

I’m running NoMachine free version 8.11.3 (amd64) on Ubuntu 22.04 LTS. For reasons (see below), I need to run the NoMachine player with hardware accelerated decoding disabled. This parameter is set in ~/.nx/config/player.cfg. However, this file is overwritten whenever I try to connect to another machine, and the parameter setting reverts back to “true”.

My current workaround is to set the permission of the player.cfg file to 400 (read only). If the permissions are set this way, the config file is unchanged, hardware decoding is disabled, and the player works. If the permissions are 600, the file is overwritten, and the player exits shortly after my password is authenticated.

This is not an elegant solution, and I’m wondering if I’m approaching the configuration file in the wrong way. Is there a way to do this that desn’t involve “hacking” the file to ensure it isn’t overwritten?

Thanks!

 

* Reasons:

My institution uses a firewall, so I can only access the primary server through SSH. The free version of NoMachine doesn’t work (directly) via ssh, so I create a tunnel from my machine to the primary server. This allows me to point my first client at localhost, and it tunnels into the primary server. From there, I need to access the desktop of another computer behind the firewall, the secondary server. So I startup the NoMachine client again on the primary server, and I then connect to the secondary server via a second connection. It is this second connection that fails when hardware decoding is enabled, presumably because the first connection is tunneled through SSH.

Once it’s set it works quite well, even if it is a bit of a hack. I totally understand if this isn’t supported, especially since I’m using the free version.

[Tor]

Hi. I can think to a couple of reasons:

• CFG file is edited while a player is running, so on saving current process overwrites your manual editing

This is easy to check, and honestly I think you verified it already, but it’s better to be sure.

• CFG file gets corrupted and the player creates a new one with default values

This would require more investigations, but we can start by doing two things: check if you see segmentation faults reported for nxplayer process in your system log, and try to edit more key values in the CFG so you can verify if they all change when the “overwrite” occurs (assuming you excluded the first possible issue I listed above). Also, check if in the $HOME/.nx/config folder you see files with extension .BCK or .RECOVER

[nfitzkee]

Thanks for the response!

I think I may have figured this one out on my own. Eventually, after searching around the server settings, I found an option where I could disable hardware acceleration. Clicking this seemed to result in a persistent selection. Since NoMachine is normally always running, I suspect you’re right that this was getting clobbered for that reason, even though this is technically the player, not the server. (I’m still a little confused on what all the apps do and how they integrate).

I also think I found a better way to log in through a firewall that involves chaining SSH tunnels. Essentially, one creates a tunnel to the first machine; then one creates a tunnel to the second machine. Once the chain is established, you connect your viewer from the originating port on your local machine, which “magically” connects to the desired client beyond the firewall.

There are a couple of ways to do the chaining, one of which is more secure (with more overhead) and one of which could involve someone using your tunnel (but with less overhead). Metaphorically, the first is like a tunnel within a tunnel, where each link is telescoping as the reach gets farther into the remote network. The second is like cramming two straws together at each connection point (no telescoping).  Both approaches seem to work. It’s pretty nifty and should save me a lot of time driving to work to check on things.

Thanks again!

[Britgirl]

Thanks for letting us know. SSH tunnels aside, if you have any other questions about player and the server, or other components of NoMachine software, let us know here 🙂

[Author]

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