Nope, that editable FAT partition is actually the EFI boot partition. IIRC, the grub config in that partition isn't actually used, only the EFI bootstrap files. Once it can access the config on the main .iso partition it loads everything from there.
Gregory Young -----Original Message----- From: CentOS <centos-boun...@centos.org> On Behalf Of Jerry Geis Sent: October 4, 2019 1:08 PM To: CentOS mailing list <centos@centos.org> Subject: Re: [CentOS] USB ISO for CentOS 8 >Then generate the .iso: ># cd /tmp/rhel7/ ># mkisofs -o /tmp/rhel7test.iso -b isolinux/isolinux.bin -J -R -l -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -eltorito-alt-boot -e images/efiboot.img -no-emul->boot -graft-points -V "RHEL-7.7 Server.x86_64" . >^^^ Change the "-V" label accordingly for CentOS 8 to match the CentOS >8 disk label. >And the critical command for USB drive booting: ># isohybrid --uefi /tmp/rhel7test.iso I was "thinking" all that was not needed - the second partition is "editable" - I change the file - I just need to regenerate grub right - not the whole ISO. I was hoping that is why they split this out into two partitions - for just such an occasion? Just want to add a menu option. THanks, Jerry _______________________________________________ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos _______________________________________________ CentOS mailing list CentOS@centos.org https://lists.centos.org/mailman/listinfo/centos
