The session directories in the user's home/.nx server side explained

Added on: 2013-12-13 Last Modified: 2015-02-03
ID: AR12K00765 Applies To: NoMachine Server

For each connection, NoMachine creates a number of session directories in the user's home/.nx directory on the server host. These directories contain files necessary for the client-server connection, and also log files. NoMachine's default setting will delete these files once the connection is terminated, unless NoMachine is configured to preserve old session files, for example for debug purposes.

The directory types and their purpose

If you look at your .nx directory on the server while you have a connection running, you can see one or more C-hostname-display-sessionID directories and a S-hostname-display-sessionID directory.

The C-hostname-display-sessionID  directories are for managing the connection to the physical desktop or to the virtual desktop. 

The M-hostname-display-sessionID  is related to the client monitor run for each connection.

For example, when creating a new virtual desktop, you will have directories similar to:



To know why the server creates two entries for each new virtual desktop please read here:

When you terminate a session,  all the session directories are deleted from your .nx on server side unless NoMachine is configured to preserve them. When you disconnect your virtual desktop, a C-* and the S-* directory is left in your .nx to be ready for the reconnection.

When NoMachine is configured to keep old session files, a session that is correctly terminated is renamed as T-C-*. For example:

C-nxtest30-1002-EBB6F9F1F366DC8240D8560F2829A228 will become: T-C-nxtest30-1002-EBB6F9F1F366DC8240D8560F2829A228

When you find a F-C* or a F-S* directory in your .nx , it means that something went wrong and the session or the client monitor has been terminated unexpectedly or in an unclean way. 

Deleting directories

You can safely remove all T-C*-*,  F-C-* and F-S-*  directories.

Deleting a C-* or a M-* directory can cause the sudden termination of your current connection to the session.

Here's how to configure NoMachine to delete the old session directory (this is the default behavior) or keep them. Edit the node configuration file, namely node.cfg, uncomment and set the SessionLogClean key as you need.

- Delete all the session directories when the session is terminated:   SessionLogClean 1 

- Keep the session directories for future references:   SessionLogClean 0

When SessionLogClean 0 is set, the session directories will be renamed as T-C-* .