2x Drives SHR (without data protection) Can I swap one?

Hi All - I've just upgraded from my VERY basic 213J to a 720+...needless to say, it's like night & day. I had 2x 3TB drives originally, but one failed a couple of years ago, replaced with a 4TB. I set them up for maximum storage rather than have redundancy, because the NAS was used as a back up for my PC Now I've found how much you can do with a faster NAS, I'm thinking of replacing the 3TB with a 6TB and having it as back up for all 4 of us in the house. I'd still use my 100GB Google Drive account though as an additional off-site solution for my pics & vids of the kids growing up etc....as my NAS box is just a few feet away from my main PC, so a house fire would mean precious memories would be lost forever! Looking at the drives in DSM I can see the larger 4TB drive is about 60% used, the smaller 3TB drive only 8%. What prep would I need to do so I can replace the 3TB with a new 6TB....is it even possible without having to start from scratch & re-copy everything over again from my PC? Thanks for any advice....

TE Terrybull asked on 18 January 2021, 16:22
2 answers / 183 views / 0 votes

Thanks for your answer Markus - I think you're right, I can't 'just swap' the 3tb with a new 6tb, so I might as well just bite the bullet and start from scratch - but with 2x 6's. I only have 2 bays in the 720+ (not got the expansion unit either) so couldn't pool the 3+4+6. Thanks for your input though, appreciate it...


I'm quite sure you cannot just swap one disk if you do not have data protection.

There could be better ideas, but I you really want to swap the 3 TB with a 7 TB, then this is my advice:

  • Buy the new 7 TB drive, connected it somewhere and copy everything over to that disk.
  • Then re-install the NAS volume with SHR (with data protection!), using the 3+4 TB disks (which will wiping everything on them).
  • You'll only be able to fit around 3 TB of data on that setup, but it seems like that should be enough.
  • Then remove the 3 TB disk and stick the 7 TB in there. Let it rebuild.

But - that approach will not give you much more space. The data protection will limit it to the size of the smaller 4 TB disk. It will, however, make sense if you at some point want to remove the remaining 4 TB disk and replace it with a 7 TB disk - you'll then get all the space available.

I would have kept the all disks, 3+4+7, but you'll still waste some TBs. See https://www.synology.com/en-us/support/RAID_calculator?hdds=3%20TB%7C4%20TB%7C6%20TB if you have not already.

Good luck!