[blue68f100]

NOT failing, but dropped form the array at the sametime, would indicate a controller/system problem.

What did the actual log show? Can you send this to me.

It's very odd to loose 2 at the same time. Looking at the info closely both drives 3 & 4 seperated from the array, and HAVE THE SAME ID ?...... These are suppose to be unique.

Do you have 4 new drives? If so make a backup set using dd. Then work off of your backups. Then if something goes wrong nothing is lost.

You said it rebuilt after installing 1 NEW drive or 2 at the same time?
A drive will/should only join the array after being made a HOT SPARE. The snap should have auto fromat the new drive. Then you have to make it a hot spare for it to join the array. This is all done through the web interface.

"co de config raid 10000 10008 10010 10018" would build an 4 disk array, but like you don't know if it would wipe your data out.
or
You might try a "co de resync 60000", but again have NO IDEA what will happen. If the cmd is not valid it will tell you.

Contact Mister_Bill, he has several of these units and may have run into this odd problem before.