I have also encountered this bug on CentOS 7 running inside a Virtualbox development environment. Refreshing as @kanshi suggested sometimes solves the problem.
The problem was partially fixed in 5.8.3 in the issue
Unfortunately, I can see it still persists in some way in 5.8.4. I have opened a new issue
Can you please confirm which OpenNebula version are you running (5.8.1 or 5.8.4 or different)? Do you have any patches applied (e.g., Jorge’s
export.js above)? Thank you!
This worked for me.