Access to the ELvis cluster nodes is restricted using IP whitelisting, as a security measure. This means that in order to connect to an ELvis node, you need to have one (or more) of the IP addresses from which you want to connect registered. You can request access at email@example.com. Note that in general IP ranges for the Dutch universities will have been registered already, so just try to connect first, it may already work.
Once you're logged into
elvis.surfsara.nl and you have secured a reservation for a render node you can log on through to that node, if needed. Note that for general usage you only need to access
elvis.surfsara.nl, make a node reservation, start a VNC session and connect to it with your VNC viewer. Command-line access to the other nodes usually isn't necessary for this kind of usage. Within your VNC session you can, of course, open a terminal to perform command-line operations.
The render nodes have hostnames of the form
Normally, an OpenGL-based visualization application running on your local machine will send OpenGL rendering commands to the GPU and let it handle the rendering and displaying of the output. The ELvis cluster is slightly different in this respect, as the rendered output needs to be transfered back to the user. To accomplish this in a fairly user-transparent manner the packages VirtualGL and TurboVNC are used on the cluster. VirtualGL provides a way to intercept the rendering output of an OpenGL-based application with high performance, while TurboVNC is capable of compressing and serving that output on-thy-fly. OpenGL applications do not have to be modified in any way in this scheme, but the user does need to use an extra command when starting applications, which will be described below.
In general, the steps to use the service are shown below. For a detailed walk-through of a remote visualization session see the document at the end of this page.
/opt/TurboVNC/bin/vncpasswd. Please use a password different from your SURFsara CUA password! . Please check if the directory
$HOME/.vncexists, and if not, create it by hand and again set the VNC password.
/sara/sw/remotevis/scripts/rvs_vncto request a VNC session on a node from the resource allocation system for a certain amount of time, e.g
<hostname>:<displaynumber>part will be the same, though.
-r <w>x<h>option to
rvs_vnc. Or set the
RVS_VNC_RESOLUTIONenvironment variable in your
.bashrc(or similar config) file, to not have to use