Trouble Installing Omniverse Nucleus -"The collaboration service appears to be unresponsive"


I am trying to set up a basic local nucleus in order to run IsaacSim on my Ubuntu 18.04.

IsaacSim is installed and runs, but can’t get the nucleus to install properly in order to get access to the assets.

When I get to the nucleus tab, and I setup a new local nucleus, the installation seems to go through without trouble.

However, it gives me this message:

Moreover, when accessing localhost:3080, I get an error message “Cannot connect to System Monitor Backend”, no services are listed under Apps, and there is no other tabs on the page other than Apps.

Finally, localhost:8080 is unable to connect.

For troubleshooting :

  1. I uninstalled the nucleus through the launcher and re-installed, no effect.

  2. I went through the cleanup procedure here : . Then re-installed first the cache then the nucleus. Same problem appears.

Here is my launcher.log :
launcher.log (16.2 KB)

And here is the system monitor logs:
logs.txt (4.4 KB)

Any Ideas why this is happening and what i could further try?


Hello @eugene.valassakis15! Welcome to the Community! I have directed your post to the development team. Thanks for reaching out!

Thank you very much for the quick reply! I appreciate the help, and am looking forward to solve this issue and start playing around with IsaacSim!

Hello @eugene.valassakis15! The dev team would like some more information to help troubleshoot your issue.

Also, try looking at localhost:3080 through Omniverse System Monitor and let us know what happens.

Omniverse System Monitor can be found here:

  • On Windows, type Omniverse System Monitor into the search bar and hit Enter
  • Also found at : C:\Users\<USERNAME>\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\NVIDIA Corporation

Hello Wendy,

Thank you very much for the help and the quick reply!

I am using Linux Ubuntu 18.04, not Windows, so I’m not sure how to get the system monitor in any other way other than the browser.

Nonetheless, as I launched Omniverse today to check if I could find the information you asked, it prompted me for an update to the version 1.2.13.

When the update completed, Nucleus started working!

So for reference it seems the issue was occurring for Ubuntu 18.04 with an Omniverse version earlier than 1.2.13.

I’m not sure if my query prompted any such version change or if it’s simply nice coincidence, but it all seems to be working now.

That’s terrific news! I am so glad it is working for you. Please don’t hesitate to reach out to us again if you need anything.