Luke and Dahu each have a visualisation node, i.e. a node dedicated to running software environments that include graphical interfaces. Anyone can access these nodes by following the procedure below.
To access the visualisation nodes, you will need to install a VNC client on your personal computer. We do not provide support for this. From experience, TigerVNC works quite well.
Sometimes you will need software or libraries that are not installed on the visu node. In this case, please contact us at sos-calcul-gricad@univ-grenoble-alpes.fr so that we can find the best way to make them available to you.
To submit a visualization job, simply run the visu_sub command from the Dahu front end as follows:
bouttiep@f-dahu:~$ visu_sub -p admin
[VISUNODE] Adding visu restriction
[ADMISSION RULE] Modify resource description with type constraints
OAR_JOB_ID=14423394
Waiting job 14423394 to be running..
You can launch your VNC viewer on the address:
dahu-visu:1
Password: 29733519
Note: This password is only valid ONE time. If you want to generate
another
password for this session then type:
OAR_JOB_ID=14423394 oarsh dahu-visu /opt/TurboVNC/bin/vncpasswd
-o -display :1
To connect to your remote X desktop, you have to launch a vncviewer on
your
local workstation, via the Ciment ssh gateway. For example:
vncviewer -via trinity.u-ga.fr dahu-visu:1
As indicated in the output of the visu_sub command, once the job is launched, from your machine, you just have to launch your VNC client with the following command (to be adapted according to the client installed on your machine):
vncviewer -via trinity.u-ga.fr dahu-visu:1
If the connexion via trinity does not work, you can try the same command passing through the other bastion, rotule:
vncviewer -via rotule.u-ga.fr dahu-visu:1
For this procedure, you must have set up your SSH connection to GRICAD clusters as explained here
On certain operating systems, the vnc client (turbovnc on MacOS for example) uses an internal ssh client. It is not compatible with the GRICAD SSH configuration and throws a java.net.UnknowHostException: f-dahu.ciment error. If this is the case, you must ask your vnc client to use the system ssh client. For turbovnc this can be done by adding -ExtSsh=1 to the vncviewer call.