mdadm - Swapping 500GB disks for 1TB

Hi,

I have a three disk raid 5, with 500GB disks.

This is close to being full, and whilst I can just add another disk and rebuild to add another 500GB, I would prefer to replace with 1TB disks. So i have some questions.

Can I replace these disks one by one with bigger disks? I understand there is a risk here, as there was when I went from RAID 0 to RAID 5, but I am happy to accept them.

I plan to buy 2x1TB disks, and pair two of the old 500GB disks into a 1TB volume. Giving a raid 5 over 3 1TB disks.

I figured it was possible doing the below, but it will take me a week! Is there a better way?

Converting 1TB raid (3x500GB - Raid 5) to 2TB raid (3x1TB)

1) Add new 1TB disk to box
2) Copy data to new 1TB disk from old 1TB raid.
3) Remove old array
4) Add another 1TB disk and create RAID 0 with other disk.
5) wipe the old array, add two 500GB as 1TB volume
6) Convert 2TB RAID 0 to Raid 5.

I have done something similar, i.e. raid 0 - raid 5, but it took alot of time, and its a high risk strategy.

Anyone got any ideas?

Cheers

Si

An easier way might be this. If you have enough space on the 1TB drive to fit all your data, then add 1 1TB drive after failing out 1 of the RAID 5 drives. Copy your data. Remove the other drives in the RAID 5 and use the remaining drives to create an md RAID 5 with 1 drive missing. You can specify that you are doing so
Copy the data from the single 1TB drive to the array, then add that drive to the array after initializing it.