Invalid Hostname Error when going to JIRA (Server version)

[Adam White]

We just started getting this error when trying to log into JIRA:

Bad Request - Invalid Hostname

---

HTTP Error 400. The request hostname is invalid.

I made no changes to JIRA since yesterday, and I tried restarting the service. JIRA does not indicate any errors in the log file either. Any ideas on what this could be? I tried seeing if I could connect to Confluence and that seems to work out fine. Is there a specific log file that can help me here? I looked at pretty much all of them.

[Justin Alex Paramanandan]

1. Are you using IIS or any server to redirect JIRA + Confluence? Or just standard deployment (using Tomcat)?
2. What are the port numbers for:
   • JIRA?
   • Confluence?
3. Any context path for both of the mentioned applications in (2)?