Adaptec 2100s
The message:
PCI: unable to reserve mem region #1:...... for device 0000:00:09.0
is the most likely place where the system failed. The driver could not initialize properly, so the RAID cannot be used and your system goes to "waiting for root filesystem".
If the message actually tells you what the memory region is, write it down and when you're dumped to busybox, try to find out what device took that memory away:
less /proc/iomem
(Or 'more' if your busybox doesn't support 'less'.)
You may have to do things like change PnP settings via BIOS or even disable a device which conflicts with your RAID.
I have no idea why it booted and installed fine but you have problems with the reboot.
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