# Desktop App - NoVNC - Failed to connect to server

**URL:** <https://discourse.openondemand.org/t/desktop-app-novnc-failed-to-connect-to-server/4500>\
**Category:** Get Help\
**Created:** [September 2, 2025, 2:52pm UTC](https://discourse.openondemand.org/t/desktop-app-novnc-failed-to-connect-to-server/4500 "2025-09-02T14:52:58Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![rachettia](https://sea1.discourse-cdn.com/flex015/user_avatar/discourse.openondemand.org/rachettia/32/2960_2.png) [@rachettia](https://discourse.openondemand.org/u/rachettia)\
**Post date:** [September 2, 2025, 2:52pm UTC](https://discourse.openondemand.org/t/desktop-app-novnc-failed-to-connect-to-server/4500/1 "2025-09-02T14:52:58Z")

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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](https://discourse.openondemand.org/uploads/short-url/e1p7SQHtNIXDnaz7zVziJslpzIC.txt) (3.6 KB)

[websockify.log.txt](https://discourse.openondemand.org/uploads/short-url/tev9Ox2KOBiv0hZNejdiSXdO9N3.txt) (129 Bytes)

[vnc.log.txt](https://discourse.openondemand.org/uploads/short-url/uG7czNP02vIdWHmWT26st4yZy7B.txt) (1.3 KB)

[output.log.txt](https://discourse.openondemand.org/uploads/short-url/pn5rJ4wOwdf2AAvm8d0fBDUQvNn.txt) (2.4 KB)

> [@Desktop app fails to connect](https://discourse.openondemand.org/t/desktop-app-fails-to-connect/2954):
>
> Hello, I am working on a fresh install of OOD on Ubuntu 22.04 (migrating from CentOS 7). All dependencies seem to be installed but running into the following issue: Setting VNC password... Starting VNC server... WARNING: n006.cluster.pssclabs.com:1 is taken because of /tmp/.X1-lock Remove this file if there is no X server n006.cluster.pssclabs.com:1 Killing Xvnc process ID 754372 Xvnc process ID 754372 already killed Xvnc did not appear to shut down cleanly. Removing /tmp/.X11-unix/X1 Xvnc did…

> [@noVNC: Failed to connect to server](https://discourse.openondemand.org/t/novnc-failed-to-connect-to-server/2304):
>
> Hi all, I have recently managed to get an installation of OOD going on my hpc. I have added a desktop app by cloning the “bc\_desktop” repo [here](https://osc.github.io/ood-documentation/master/enable-desktops/software-requirements.html). The desktop app successfully launches but I get a “Failed to connect to server” on the noVNC page. The output.log is below: Setting VNC password... Starting VNC server... WARNING: n002.cluster.com:1 is taken because of /tmp/.X1-lock Remove this file if there is no X server n002.cluster.com:1 Killing Xvnc process ID 158023 Xvnc process ID 158023 alrea…

> [@Unable to start xfce desktop](https://discourse.openondemand.org/t/unable-to-start-xfce-desktop/2920/7):
>
> I solved it! The error above was overcome by fixing the permissions on /tmp (it was not writable for some reason). I found that this was an issue by running Xvnc manually and seeing that Xvnc failed to create a “/tmp/.tX1-lock”. There was no other system error log, so it was tough to figure out until I did this manual run. After that, the “Launch Desktop” button was finally visible. But, clicking it resulted in “Failed to connect to server” in the VNC console. By reading a prior topic here, I f…

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**Author:** ![jeff.ohrstrom](https://sea1.discourse-cdn.com/flex015/user_avatar/discourse.openondemand.org/jeff.ohrstrom/32/136_2.png) [@jeff.ohrstrom](https://discourse.openondemand.org/u/jeff.ohrstrom)\
**Post date:** [September 2, 2025, 3:17pm UTC](https://discourse.openondemand.org/t/desktop-app-novnc-failed-to-connect-to-server/4500/2 "2025-09-02T15:17:09Z")

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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:

```auto
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:

> <https://github.com/OSC/osc-ood-config/blob/0e47f2b6192d020734d6cc358effc6391f03ce2a/ondemand.osc.edu/apps/bc_desktop/submit/slurm.yml.erb#L82>

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

> **[submit.yml.erb — Open OnDemand 4.0.0 documentation](https://osc.github.io/ood-documentation/latest/reference/files/submit-yml-erb.html#setting-batch-connect-options-globally)**

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**Author:** ![system](https://us1.discourse-cdn.com/flex015/uploads/osc/original/2X/b/bae70bd0ed39a3ae769c2108155f4cb3e9da8385.png) [@system](https://discourse.openondemand.org/u/system)\
**Post date:** [March 1, 2026, 3:17pm UTC](https://discourse.openondemand.org/t/desktop-app-novnc-failed-to-connect-to-server/4500/3 "2026-03-01T15:17:57Z")

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