System Administration Guide: Security Services

Setting Up Root Authentication to Mount NFS File Systems

If users want to access a non-Kerberized NFS file system, either the NFS file system can be mounted as root, or the file system can be accessed automatically through the automounter whenever users access it (without requiring root permissions).

Mounting a Kerberized NFS file system is very much the same, but it does incur an additional obstacle. To mount a Kerberized NFS file system, users must use the kinit command as root to obtain credentials for the client's root principal, because a client's root principal is typically not in the client's keytab. This step is required even when the automounter is set up. This step also forces all users to know their system's root password and the root principal's password.

To bypass this step, you can add a client's root principal to the client's keytab file, which automatically provides credentials for root. Although this solution enables users to mount NFS file systems without running the kinit command and enhances ease-of-use, it is a security risk. For example, if someone gains access to a system with the root principal in its keytab, this person can obtain credentials for root. So make sure that you take the appropriate security precautions. See Administering Keytab Files for more information.