As you probably know, the chattr and lsattr commands set and view file = attributes in Linux and other UNIX OSes. The immutable flag is = interesting because it prevents even root from modifying the file when = it is set. However, root can casually set or remove the flag any time = so it does not stand as a difficult barrier. =20 I understand that in HP-UX you have to be in single-user mode to change = this attribute. Is there a way to make Linux act in the same manner? = This would be a nice security restriction if critical files could not be = modified except by root in single-user mode. Does anyone know a way to = do this? Thanks, Brian