NoMachine entries for virtual desktops in the server session list explained (v. 4)

Transcription

1 NoMachine entries for virtual desktops in the server session list explain (v. 4) Page 1 of

2 This article applies only to those NoMachine server products for Linux supporting virtual desktop sessions. When the user creates a new virtual desktop, closes (i.e. disconnects) or reconnects a virtual desktop, the NoMachine server updates its session list accordingly. Premise It's necessary to distinguish among the following cases: 1. Lightweight Mode Enabl (default) 1.1. Creating a New Virtual Desktop 1.2. Disconnecting a Virtual Desktop 1.3. Reconnecting a Virtual Desktop 2. Lightweight Mode Disabl 2.1. Creating a New Virtual Desktop 2.2. Disconnecting a Virtual Desktop 2.3. Reconnecting a Virtual Desktop 1. Lightweight mode enabl This is the default. You can verify your settings from the NoMachine server status -> Performance GUI and the 'Use lightweight mode in virtual sessions' option. As an alternative, verify if the AgentLightweightMode key is enabl in the node configuration file (/usr/nx/etc/node.cfg). Note that in a multi-node environment, you should verify settings for each node Creating a new virtual desktop When the user chooses 'Create a new virtual desktop', the server creates a new desktop, i.e. it starts the X server on the first available display. This desktop is list in the session list and corresponds to the entry with the actual DISPLAY. Status of the virtual desktop session is 'Connect', the session type is 'unix-xsessi' Page 2 of

3 nomachine B0FD02. localhost: nomachine B0FD Connect localhost:22 unix-xsessi This virtual desktop entry in the session list corresponds to one nxnode process. You can see that by running the 'ps -ef grep nxnode' command. In the same context of the example above, the output of 'ps -ef grep nxnode' can be similar to: # ps -ef grep nxnode gdm :38 pts/2 00:00:00 /usr/nx/bin/nxnode.bin :39? 00:00:01 /usr/nx/bin/nxnode.bin -H 8 --shell Note that the nxnode process relat to the user's connection is the process running with the -H option. The nxnode process own (in this example) by gdm is the node in charge of mirroring the physical display. This nxnode process is necessary to let users connect to the physical desktop of the host machine and it's not start when the machine is headless or the X server is not up and running Disconnecting a Virtual Desktop When the user disconnects from the virtual desktop, such desktop remains running. The NoMachine server updates its entry in the session list and changes status to 'Disconnect' nomachine - 5B0FD02. localhost: Page 3 of

4 1002 nomachine - 5B0FD Disconnect localhost:22 unix-xsessi If the user logs out (i.e. terminates the session), the virtual desktop is terminat. Its entry will be remov from the session list and disappear from the nxserver list output. The session history will report such session as 'Finish'. For further information on how to disconnect or terminate a virtual desktop session and the differences between them, please consult the following: Reconnecting a Virtual Desktop When the user reconnects the virtual desktop, NoMachine server updates entries in the session list. In this case, the session list will show two entries: one for the X server start when the virtual desktop has been creat (it's the unix-xsessi session type), and one for the reconnection (it's the shadow session type). Both sessions will be in status 'Connect' nomachine A localhost: nomachine B0FD02. localhost: nomachine A Connect localhost:22 shadow nomachine B0FD Connect localhost:22 unix-xsessi 2 Note that the reconnect session will have a different Session ID from the session originally connect when the virtual desktop was creat. Additionally, it could also be reconnect on a different Display. 2. Lightweight Mode Disabl Page 4 of

5 Lightweight mode can be disabl from the NoMachine server status -> Performance GUI by unselecting the 'Use lightweight mode in virtual sessions' option. As an alternative, disable the AgentLightweightMode key in the node configuration file (/usr/nx/etc/node.cfg). Note that in a multi-node environment, you should verify settings for each node Creating a New Virtual Desktop When the user chooses 'Create a new virtual desktop', the NoMachine server executes two operations: a) It creates a new desktop, i.e. it starts the X server on the first available display. This desktop is list in the session list and corresponds to the entry with the actual DISPLAY. Let's call this entry 'display session', it's the 'unix-xsessi' session type and it has status 'Disconnect'. b) It adds the user s connection to the session list: this is the entry in the server session list showing the IP of the connect client. It's a 'shadow' session type and has status 'Connect' nomachine AD. localhost: nomachine - 949CA6F. localhost: nomachine AD Connect localhost:22 shadow 1002 nomachine CA6F Disconnect localhost:22 unix-xsessi These entries correspond to two nxnode processes: one is the display session itself, the other is the user's session connect to that display. Page 5 of

6 You can see the nxnode processes by running the 'ps -ef grep nxnode' command. In the same context of the example above, the output of 'ps -ef grep nxnode' can be similar to: lightdm :46 pts/0 00:00:00 /usr/nx/bin/nxnode.bin nomachine :4 pts/0 00:00:0 /usr/nx/bin/nxnode.bin nomachine :4 pts/0 00:00:00 /usr/nx/bin/nxnode.bin -H 6 You can recognize the nxnode process of the user's connection because it is running with the -H option. The other nxnode process own by 'nomachine' is the display session. The nxnode process own (in this example) by lightdm is the node in charge of mirroring the physical display. This nxnode process is necessary to let users connect to the physical desktop of the host machine and it's not start when the machine is headless or the X server is not up and running Disconnecting a Virtual Desktop When the user disconnects from the virtual desktop, the NoMachine server updates its entries in the session list. The display session remains running and maintains status 'Disconnect'. The session entry relat to the user's connection disappears from the output of 'nxserver --list' and it's status is chang to 'Finish' in the session history nomachine - 949CA6F. localhost: nomachine nomachine AD. 949CA6F Finish localhost:22 shadow Disconnect localhost:22 unix-xsessi If the user logs out (i.e. terminates the session), both desktop and connection entries are remov from the session list and disappear from the nxserver list output. The session history will report such session as 'Finish'. For further information on how to disconnect or terminate a virtual desktop session and the Page 6 of

7 Power by TCPDF ( NoMachine entries for virtual desktops in the differences between them, please consult the following: Reconnecting a Virtual Desktop When the user reconnects the virtual desktop, NoMachine server updates its entries in the session list. Also in this case, the session list will show two entries: one for the display session (it's the unix-xsessi session type, with status 'Disconnect'), and one for the reconnection (it's the shadow session type with status Connect) nomachine F2D5. localhost: nomachine - 949CA6F. localhost: nomachine nomachine F2D5. 949CA6F Connect localhost:22 shadow Disconnect localhost:22 unix-xsessi Note that the reconnect session will have a different Session ID from the session originally connect when the virtual desktop was creat. Additionally, it could also be reconnect on a different Display. Page of