For the board, look at the sharing options and make sure they are only granted to the project, or a group with those six users.
For the project, it's a bit more complex. Look at the permission scheme for the project, and look at who can "browse project" - you need to make sure it is only your six users who can do this.
If you have a good scheme, it will probably say "browse project: role (users)". This is good because it means you can go to the "people" section in the project and remove any group or user you don't want to see this stuff (e.g. the "jira-software-users" group, which is the same as "anyone who can log in"). If it says something else, you're going to have to think a bit more about it.
The Jira Marketing team is putting together an ebook on migrating to Data Center. We're looking for pro tips on how you staffed your project team and organized your Proof of Concept. Share yo...
Connect with like-minded Atlassian users at free events near you!Find a group
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no AUG chapters near you at the moment.Start an AUG
You're one step closer to meeting fellow Atlassian users at your local meet up. Learn more about AUGs