With help from my other Q&A here, I am able to get the ISO to boot, but not install it (yet :-/).
As per some Launchpad posts, the normal initrd present in the ISO will always look for
CD-ROM. So, I replaced it with the initrd designed for hd-media from here:
http://archive.ubuntu.com/ubuntu/dists/bionic/main/installer-amd64/current/images/hd-media/initrd.gz http://archive.ubuntu.com/ubuntu/dists/bionic/main/installer-amd64/current/images/hd-media/vmlinuz
(although, I am not sure what is the exact difference)
With this, I could get past the CD-ROM mount, but installation gets into mount problem.
My ISO is on /dev/sda5, so when asked to unmount /dev/sda, I said "No", later it goes a
step further and errors out like "no root file system defined" etc.
Tried: https://bugs.launchpad.net/ubuntu/+source/debian-installer/+bug/1347726
Didn't help.
Also tried using toram in the command line as per this - didn't help.
I am using Ubuntu 18.04.4 server ISO here. However, just to try, I used Ubuntu 18.04.5 Desktop (live
CD boot) and that installed fine (even though it gave the error for mounted /dev/sda!)
What exactly is the delta that is missing in Server ISO that is present in Desktop /Live ISO
which makes this work!?
All I want is to install an ISO which is residing on one partition /dev/sda5 to another -
/dev/sda2 or /dev/sda6
