SSO: strange behaviour (Openfire 3.6.4, Spark 2.6 beta)

Hi there!

I’m running Openfire 3.6.4 in a Fedora box and Spark 2.6 beta in our XP sp3 clients. I’ve configured SSO following the documents in the community and it is working perfectly… sometimes.

I dont know why , if nothing have changed in either client or server side, the connection goes on perfectly using SSO and sometimes (normally after a workstation reboot) it wont get through, the log file showing the message:

“javax.security.sasl.SaslException: GSS initiate failed [Caused by GSSException: No valid credentials provided (Mechanism level: Server not found in Kerberos database (7))]”

I’m quite certain the cause of this error lies in a dns problem, for I’ve changed the sso method and the problem persists no matter which one I choose (file with krb5.ini , dns or manual). And then, I need to make a modification in the workstation dns settings just as changing the dns server order or such, and then revert them back to the old settings in order to make sso work again. Until -maybe- the next reboot.

Any ideas?

Thanks!