On 05/08/2025 at 10:42, Fab Stz wrote:
I have an external device with multiple partition. Among them, there is one partition with Clonezilla (which is based on Debian), and one partition with the debian trixie installer. Both copied from their respective ISO.The debian installer seems to be satisfied once it detected Clonezilla partition and seems to consider that this is the debian installer media.But installation will fail because there is no Release file on this partition (which is expected).
The "cdrom" detection is performed in cdrom-detect postinst script in two steps: 1) Search and mount the first CD, USB partition or disk which has an ISO9660 or FAT filesystem and a /.disk/info file. 2) Extract the suite and codename from the first /dists/*/Release file and fail if the file is missing or does not have the expected format.
I have seen the same flawed logic in other parts of the installer (e.g. firmware file search): stop at the first item which matches the first condition, and fail if it does not match the next condition. Instead it should check all conditions on each item until an item which matches all conditions is found.
There is another related issue: if different versions of Debian installer media are present, the installer may pick the wrong one and install the wrong version or fail because kernel modules are missing. Each installation image has a unique identifier in /.disk/id/, but the installer's initrd does not know about it. The identifier could be added to the kernel command line in the boot loader configuration or to the initrd when the CD image is built.