Desktop App - NoVNC - Failed to connect to server

rachettia · September 2, 2025, 2:52pm

When attempting to launch an Interactive desktop via Open Ondemand server receiving the following message of “Failed to connect to server - NoVNC”.

I’ve looked at the documents below but have been unable to resolve the issue with the interactive desktop failing to make the connection.

I open up developer tools in Firefox and there appears to be an issue with the websockify connection and the vnc password input.

I was hoping you could take a look at the log files and let us know what we maybe missing or over looking.

developer-tools.txt (3.6 KB)

websockify.log.txt (129 Bytes)

vnc.log.txt (1.3 KB)

output.log.txt (2.4 KB)

jeff.ohrstrom · September 2, 2025, 3:17pm

Hi and welcome!

As an initial check - I’d like to ensure that node_uri and rnode_uri are enabled in the ood_portal.yml and that their Location directives are in ood-portal.conf.

If they are and that all looks good, these are the errors I’d hone in on:

error: XDG_RUNTIME_DIR is invalid or not set in the environment.
error: XDG_RUNTIME_DIR is invalid or not set in the environment.

You can see here how we set this at OSC:

github.com/OSC/osc-ood-config

ondemand.osc.edu/apps/bc_desktop/submit/slurm.yml.erb

0e47f2b61


      
          
            image = '/apps/project/ondemand/singularity/mate-rhel8/mate-rhel8.sif'
          -%>
          ---
          batch_connect:
            before_script: |
              # Export the module function if it exists
              [[ $(type -t module) == "function"  ]] && export -f module
          
              # MATE acts strange in pitzer-exp and doesn't like /var/run/$(id -u)
              export XDG_RUNTIME_DIR="$TMPDIR/xdg_runtime"
          
              # reset SLURM_EXPORT_ENV so that things like srun & sbatch work out of the box
              export SLURM_EXPORT_ENV=ALL
          script:
            accounting_id: "<%= account %>"
            native:
              <%- slurm_args.each do |arg| %>
                - "<%= arg %>"
              <%- end %>

Additionally, you can set these configurations globally for the whole cluster file in the cluster.d file:

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Desktop App - NoVNC - Failed to connect to server

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