Description of problem: Currently firefox is not accepting any kerb tickets. On fedora 25 this was working. No changes have made to my krb5.conf. And currently I am able to use my kerb tickets for ssh and other applications. Just not via firefox. Version-Release number of selected component (if applicable): [alemay@wopr ~]$ rpm -qa | grep firefox firefox-55.0.1-1.fc26.x86_64 [alemay@wopr ~]$ rpm -qa | grep ^krb krb5-workstation-1.15.1-22.fc26.x86_64 krb5-libs-1.15.1-22.fc26.i686 krb5-devel-1.15.1-22.fc26.x86_64 krb5-libs-1.15.1-22.fc26.x86_64 How reproducible: 100% Steps to Reproduce: 1. kinit 2.open firefox to a website that requires kerb ticket 3. Actual results: Site to fails properly authenticate Expected results: Site to properly authenticate Additional info:
Switching [libdefaults] dns_canonicalize_hostname = false to [libdefaults] dns_canonicalize_hostname = true Fixes this problem.
*** This bug has been marked as a duplicate of bug 1481655 ***