SharePoint 2013 Crawl Access Denied Error

I usally can fix these crawl errors fast. DisableLoopbackCheck, Check Web App permissions, check DB permmisions…

But all was configured correctly. All other web apps were being index and running smooth. I just had one web app that would not get indexed. I even deleted the web app and recreated the site since it was a QA server.

Even the logs were not very clear. Just some access denied to robots.txt. I dont even use robot.txt files…

After many hours i decided to ping the FQDN and that when i noticed the issue. Someone in Networking team created the DNS as a C-Name alias. Which means it would return the name of the computer and not the proper name. It was also pointed to an incorrect WFE server.  Once they changed it to a A- Record DNS Search was able to index.