Hi,
I have fresh license for JIRA 6 + AGILE with valid support to August 2016.
I have installed new empty JIRA 7 Software and during initial setup has been generated JIRA Software (Server): Evaluation license.
Now I would like to enter correct license. From this page https://confluence.atlassian.com/migration/jira-7/jira-license-compatibility-matrix I know that my JIRA 6 license should work with my JIRA 7 instance.
But when I want to preview my license in my account license manager, application requires to update Server ID.
There is even helpful message 
To get your Server ID:
- Log in as a JIRA administrator
- Click on the Settings icon and choose System
- Click on the License link
- Your Server ID is listed in the Server ID field
But of course this screen is not available in new JIRA 7 so I don't know what I should do.
If somebody could help I would be grateful.
Thanks,
Andrzej