This is normal behavior as you have to authenticate with kerberos on your client and negotiate kerberos with your browser.
On the local host, where web browser is running:
1. Configure krb5.conf with correct hadoop domain info.
2. Run kinit to obtain a kerberos ticket from KDC server.
3. Configure web browser to use the kerberos ticket, which depends on different type of web browser (More details on http://crimsonfu.github.io/2012/06/22/kerberos-browser.html).