How to debug SPNEGO on Tomcat

I have setup SPNEGO in tomcat.

I am getting the message "Downgrade NTLM request to Basic Auth." and the client 开发者_运维知识库is prompted for user name and password.

But I want single sign on.

How can I debug this?

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SPNEGO is up and running. Obviously you don't know what SPNEGO exactly is. It simply wraps several technologies. E.g, Kerberos or NTLM crap. Since your server does not support Kerberos, it tries NTLM for some reason. double-check your env.

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You aren't using a browser on the same host as your Tomcat, right? SPNEGO does not work locally; only remotely. This is the first thing to check, although there might be other reasons.