As a suggestion for next time. Since Jira Core is included with the Jira Software installer you could save yourself some time and upgrade both at the same time by using the Jira software installer instead.
Also here are the upgrade notes for Jira Software 8.1.0:
Background When you hear the words ‘Release notes’, almost always you think of an unsolicited email from a software vendor. But I am here to tell you that from our data, sending release notes via E...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events