Hello.
I have upgraded a host to Fedora 28. Using the new dracut to rebuilt initramfs, new kernel and old kernel would fail to boot. If I use the old kernel without touching the initramfs, it would boot.
I tried downgrading to old dracut and the problem persist.
The boot problem is that I can see my RAID but it failed to activate the root (/) LVM on the mdraid.
It had error message like this in dracut shell:
+ lvm pvdisplay
WARNING: PV mphetV-LMWe-se6x-86Bv-osHk-rVk2-K01UNk on /dev/sdb2 was already found on /dev/sda2.
WARNING: PV mphetV-LMWe-se6x-86Bv-osHk-rVk2-K01UNk on /dev/md126 was already found on /dev/sda2.
WARNING: PV mphetV-LMWe-se6x-86Bv-osHk-rVk2-K01UNk prefers device /dev/sda2 because device was seen first.
WARNING: PV mphetV-LMWe-se6x-86Bv-osHk-rVk2-K01UNk prefers device /dev/md126 because device size is correct.