I just installed Jira 7.2.12 on a Google Cloud Compute virtual machine. I can log in to the Jira instance from Chrome on the virtual machine. I established a security rule that allows all inbound traffic on all ports from all IPs:

However, I cannot successfully log in to Jira from any other computer. I can see the login page, but when I enter my correct username and password, the page just clears my entries and returns to the original home page as if I had entered nothing. It doesn't say incorrect username or incorrect password, login failed, or anything. It just acts as if I had done nothing. Any ideas?