How can I expand a TS-869L with larger disks?

[Fred8]

Hi there,

I've a TS-869L with original FW 3.8.1 Build 20121205 (yes, that's verry old, no question) and 8 4TB disks as RAID5 with 1 spare to get around 22TB volume.
It's working fine without any issues exept it's nearly full.

So I plan to replace the disks by 8TB disks to get something around 44TB. Because the FW is unable to expand above 16TB I have to setup from scartch.
My current plan is to

1. save settings and all data
2. update FW to actual 4.3.3, check functionality and save settings again
3. switch off and remove all old disks
4. insert 4 new disks, switch on, reinitialize and create a RAID5
5. if this is working as expected I can start to copy back the data
6. then I can put in the other 4 disks and create a second RAID5 to expand the volume

Yes, I could create a RAID6 with all 8 disks at once. This would give more robustness but if I some years later want to exchange the disks again (to get 88TB ) I have to replace all 8 at once - because we talk about 1-3 days per disk a horrible vision for me.

What are the pitfalls or are I'm wrong and how can I walk successfully?
Is it theoretically possible to switch back to old or "toggle" between old and new disk set? Just as an emergency fallback if more than all goes wrong...

Many thanks in advance
Fred

[MrVideo]

What you are describing is not expanding the volume, but creating a new volume with the new RAID and adding that volume to the storage pool. Be sure and create a thick volume and turn off snapshots.

Yes, it might take 1-3 days per disk, but the NAS will still be available.

And yes, you'd be able to turn off the NAS and swap back in all of the old drives and bring it back up. Be sure to mark which slots they were in.

Personally, I'd go with all 8 and once and use RAID6.

[Fred8]

Thanks for your fast response.

[MrVideo]

You are welcome.

[dolbyman]

with that much data..make sure you have a solid backup plan