Booting the RHEL "boot" ISO works fine, but during installation, the installer pops up the following error message:
I "unplugged" the virtually mounted boot ISO and loaded the "Red Hat Enterprise Linux" install DVD and hit "OK" to retry.The Red Hat Enterprise Linux disc was not found in any of your CDROM drives.
Please insert the Red Hat Enterprise Linux disc and press OK to retry.
Didn't work.
On the console terminal 3 (Alt+F3), I saw the following:
In console terminal 4 (Alt+F4) I saw that unplugging/replugging the DVD ISO registered a virtual CDROM properly as /dev/sr1 - instead of /dev/sr0.INFO: trying to mount CD device /dev/sr0 on /mnt/stage2
ERROR: Couldn't open /dev/sr0: No such file or directory
[SOLUTION]
I unplugged/replugged the DVD ISO. Then I choose "Back" and re-selected to install from local CD/DVD drive.
Now, it "found" the virtual drive and continued the installation.