Habe mein Problem selber mit diesem Beitrag Single Sign On setup failed (join-script fails with various errors) gelöst.
Die Gruppenzugehörigkeit war auf root
root@ucsbackup:/home/Administrator# ls -l /etc/univention/ssl/ucs-sso* /etc/simplesamlphp/ucs-sso*
-rw-r----- 1 root root 5440 Feb 7 19:53 /etc/simplesamlphp/ucs-sso.mydomain.my-idp-certificate.crt
-rw-r----- 1 root samlcgi 1675 Feb 7 19:53 /etc/simplesamlphp/ucs-sso.mydomain.my-idp-certificate.key
habe mit:
eval "$(ucr shell)"
chown root:samlcgi "${saml_idp_certificate_certificate}" "${saml_idp_certificate_privatekey}"
chmod 644 "${saml_idp_certificate_certificate}"
chmod 640 "${saml_idp_certificate_privatekey}"
geändert.
root@ucsbackup:/home/Administrator# ls -l /etc/univention/ssl/ucs-sso* /etc/simplesamlphp/ucs-sso*
-rw-r--r-- 1 root samlcgi 5440 Feb 7 19:53 /etc/simplesamlphp/ucs-sso.mydomain.my-idp-certificate.crt
-rw-r----- 1 root samlcgi 1675 Feb 7 19:53 /etc/simplesamlphp/ucs-sso.mydomain.my-idp-certificate.key
Nun hat der Beitritt vollständig geklappt.