Hello, Nidhi Kumari!
You have shared very less information that's why it won't be possible to get the right answer for you. Here are some quick Q/A for you:
- Are you using **VM**?
- Which is your `ubuntu` version?
- Do you have `sudo` privileges?
If possible, please share the installation process you did.
Here is our quick documentation: https://gluu.org/docs/gluu-server/4.0/installation-guide/install-ubuntu/
**N.B:** Currently, We have [gluu 4.2](https://gluu.org/docs/gluu-server/4.2/) running. So, I would recommend you use the latest version of gluu server.