Re: Why do arrays start without some components?

Simon Matthews wrote:

I have a couple of machines on which this is happening now --

When the machine boots, the RAID arrays (RAID 1) start, but each array
only has one component device. I can add the other component again
(using mdadm --add ... ) and the array will sync up, but next time it
boots, I have to do the same once more.

Why is this and how do I fix it?
  

Might that be a /etc/mdadm/mdadm.conf in the initramfs listing fewer 
devices than it should?
I am not sure (because in this case maybe it shouldn't autoassemble the 
array at all), but have a look by unpacking your initramfs. If yes, 
update it.
Or could that be a controller that shows the disks to the kernel too 
late... do you have multiple controllers?