We are running JIRA which is building data. We need to make some changes to the configuration of JIRA. We would like to change the configuration in a test environment, then import it to JIRA. While we are building our new configuration on a test environment, our production server continues to collect data. Now we have two environments out of synch.

How do we upgrade the production server without loosing any new data
How do we lock out all users except admin, while we upgrade