Spark is unable to find the principal to use for Single Sign-On

Spark is unable to find the principal to use for Single Sign-On. This will prevent SSO from working.

No changes to the server or clients that I’m aware of, when I go to test LDAP settings nothing happens to say it passed or failed. I can turn SSO off and login fine using my Windows credentials. Has anyone ever had SSO die on them out of the blue?

I can confirm that SSO works in both Spark 2.9.4 and nightly builds of Spark 3.0.0. Check your keytab, it may need to be recreated.

something change! last time it just “stopped” working was 7 years ago, and it was due to a change in java jre!

You may want to confirm your keytab/spn account is still valid or isn’t locked out. Are you using a krb5.ini file or dns. If dns, are you having any dns issues?