O Coraid, Coraid, wherefor art thou Coraid?
Well, it is sad that coraid has gone… Sadder still that their support is gone.
I was working on a coraid for a friend and they had two disks fail at the same time, good old raid 5 doesn’t like that too much. The new one’s are raid 6, but how to recover data off these raid5 ones? Old notes to the rescue!
First your remove the lun:
Now you need to recreate the raid but make sure to keep one drive as missing so that it will not initialize the whole array. (in this case we are leaving dirve 6 as missing and drive 0 as an optional spare – if we want to risk an attempt at a rebuild)
make -r 1 raid5 2.1-5 missing 2.7-15
Now you need to online the lun in order to see it on the servers
Now you can start copying off, but keep in mind, you may find yourself needing to do this several times to recover all the data. I have seen some successful rebuilds, others not so much so it can take a long time to copy off that data. Make sure you use a good rsync script that will pick up where it left off every time you have to resetup the array.