unable to login status 537 connection to the netbackup database was not successful

I know this is marked as solution provided. But you can use nbdb_ping to check if the dababase is up and responding.

Hello suparman7 

You may want to look at this article:
https://www.veritas.com/support/en_US/article.100051777

This is a good place to start troubleshooting. Please help us help you by providing as many details as possible about your environment to include the version of NBU that you are running.