cd /etc/postfix/certs
openssl x509 -subject_hash -noout -in telekom.crt
ln -s telekom.crt 812e17de.0
openssl x509 -subject_hash -noout -in dfn.crt
ln -s dfn.crt 6107e209.0
openssl x509 -subject_hash -noout -in fhs-ca.crt
ln -s fhs-ca.crt 74f0e817.0
chmod 644 812e17de.0 6107e209.0 74f0e817.0