I did find this in RedHat's Managing Confined Services (https://access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/6/html-single/Managing_Confined_Services/index.html#sect-Managing_Confined_Services-NFS-NFS_and_SELinux) I did not yet try to run the NFS-Server without changing SELINUX bools. I'll do this tomorrow. Regards Stephan