Report Server DNS Issue

I had an issue with my report server that the report manager URL is not working when i use it like below.
http://servername/reports
But it was working when i gave the IP address instead of hostname.
eg: http://192.168.10.1/reports
Resolution:
In order to overcome the issues with URLs and constant credential requests I changed the following settings in RSReportServer.config:

Original:
<Authentication>
      <AuthenticationTypes>
             <RSWindowsNegotiate />
             <RSWindowsNTLM />
      </AuthenticationTypes>


Adjusted to:
<Authentication>
      <AuthenticationTypes>
             <RSWindowsNTLM />
      </AuthenticationTypes>


Such changes were necessary due to the fact that there is no correct SPN set for the service account used by SSRS. If Kerberos authentication is required the correct SPN needs to be set up in prior.