I have a CentOS setup with sw RAID5 that holds my data. Well, the server died, so I bought another box to migrate my drives to. Only thing is, I cannot get the RAID array rebuilt (not even sure it needs rebuilding, might just need the /dev/md0 mapping created... but I don't even know how to determine what I need!)

Some details:

• RAID5 software (used mdadm)
• 4x 250GB drives (2 are SATA, 2 are EIDE -- would this matter? It worked fine in the other box...)
• latest CentOS distro
• built using mdadm

I've got a decent amount of experience with standard linux stuff, but the hardware level stuff runs me in circles. I've spent some time googling and elsewhere here on SF, so please be kind for my newbie questions :).

My question is this: how can I diagnose the problem? For all I know, I'm using the wrong device blocks when I try to rebuild the array, but I can't find the command to display only the devices that have some physical attachment.

Is there some simple way for me to run mdadm, having it scan over all my physical drives, and say "hey, drives 2,5,6,7 are a software array, want me to mount it?"

I basically just took the drives from my old box and put it into my new one. They show up in the BIOS. What steps do I need to take in order to get the array up, running, and mounted?

Thanks in advance!