Hi Denis,
Probably the kerberos authentication is not enforce because some things are missing. To know if the user is authenticated, run this : eos whoami
Do you have a file /etc/krb5.keytab containing the key of the principal you use to authenticate against (host/np02ss18@CERN.CH), you can check by running klist -k /etc/krb5.keytab.
Your user should also have a valid kerberos ticket created by kinit.
For what I know, you shouldn’t need any map set.