Unable to boot after modifying grub.cfg

[jmwoo]

Hello,

I am currently testing kickstart. It failed on CentOS 8.5, but succeeded on CentOS 8 Stream. However, a different issue occurred on CentOS 7.9, which is not the same as the one on CentOS 8.5.

I modified the ISO file using UltraISO, and I have identified some of the causes of the issues. I changed "set default="1"" to "set default="0"" in grub.cfg and added the following entry, resulting in two identical command lines:

menuentry 'Install CentOS 7' --class fedora --class gnu-linux --class gnu --class os {
linuxefi /images/pxeboot/vmlinuz inst.stage2=hd:LABEL=CentOS\x207\x20x86_64 quiet
initrdefi /images/pxeboot/initrd.img
}

I saved the modified grub.cfg file using UltraISO, and when I boot from the modified ISO, I encounter the following message:

starting dracut initqueue hook

Is there an issue with the way I modified the ISO file? The modification worked correctly for CentOS 8 Stream using UltraISO.