Users are authenticated by mod_auth_kerb which works great. Therefore I need to set Require valid-user If there is no valid user Apache fails with an 401 Authorization Required. I would like Apache to deliver the website anyway but not providing a remote_user to the underlying script. This is related to How to tell mod_auth_kerb to do its job despite no "require valid-user". But with the important difference that on a whole subdirectory on every url a kerberos negotation should be initiated, and if it fails it should deliver the content anyway.