Hi, i wrote: > > What ISO exactly did you use ?
Gianmarco wrote: > i downloaded ISO files from here (i have tried both format): > https://cdimage.debian.org/debian-cd/current/source/iso-dvd/ That's 11.3.0 meanwhile. But as you report to have used 11.2, i assume that it is the same ISO as i downloaded from the archives and tested a few hours ago. > I used brasero, for example. > I selected: burn ISO image. That's the correct choice. If you still have the 11.2 DVD: What do you get from dd if=/dev/sr0 bs=2048 count=1903144 | sha256sum I get 022370f066bc91b2cdac3837ff5fa9f3822c5afb2fc34f68084416079fe5a408 - as with debian-11.2.0-amd64-DVD-1.iso from which i got the count of 1903144 blocks (dividing 3897638912 bytes by block size 2048). > > So it did not actively offer you the DVD but rather you told it to prefer > > DVD over hard disk ? > yes: what you wrote is right. All in all this looks like the DVD drive does not tell the BIOS that a medium is loaded or that the BIOS does not recognize the El Torito boot record and the boot catalog on the medium. (But exactly this stuff has not changed between Debian 8 and 11.) Insofar it would be very interesting to see what above dd | sha256sum yields. Have a nice day :) Thomas