Good Afternoon,

I'm trying to re-roll a RHEL9 iso to remove the media check and 60s timeout  that occurs because rd.live.check is baked into the kernel command line and grub menu. I'd like to use the result with an unattended install.

I start by loop mounting the OEM iso image and extracting the contents to a working dir. In the working directory, I've attempted to edit EFI/BOOT/grub.cfg an isolinux/grub.cfg before rerolling the disk with:

mkisofs -o output.iso    -b isolinux/isolinux.bin -c isolinux/boot.cat    -no-emul-boot -boot-load-size 4 -boot-info-table  workingdir

But after editing either or both, I'm still presented with the 60s default timeout and the media check (rd.live.check) in the kernel commandline.

Is there something akin to grub2-mkisofs that I need to do for my changes to the grub.cfg for this iso prior to my re-rolling it?

Thank you,

Dan