A very common method of setting up ftp mirrors for Red Hat is to just download the ISO images and then loopback mount them to allow people to FTP/NFS install off of your server. Since the net install doesn't try to find the second disk at a slightly offset mount point, installs fail if anything is needed off the second disk. Not critical, but it's going to cause lots of people's installs to fail until ftp admins figure it out and then the ftp admins won't be overly happy about it.
Marked as feature request.
*** Bug 25954 has been marked as a duplicate of this bug. ***
We are going to make it so on NFS installs it scans for ISO images. We haven't decided about FTP install support.
Fixed.