DS1819+ ---> 8 x 6tb to 4 x 16tb

[BoosterT]

My DS1819+ is at 84% capacity. It currently holds 8 x 6TB drives and gives me about 42TB which Synology reports as 36.6TB (given that it reports 6TB drives as 5.5TB drives). It is used to backup contents, not as an active server. The cost of larger drives is insane in that a 16TB Seagate Exos X18 drive is only $40 more than an 8TB drive. My idea would be to buy 4 of the 16TB drive and have 48TB (which I expect Synology would see as about 42TB) ... the $64 question is how? My intuition says that I will need to basically rebuild the replacement volume elsewhere and then move the drives to the DS1819+. Moving terabytes of data is not my idea of fun, even with 10GB ethernet.

On the other hand, I still have sufficient free space to manage for a while ... so am I being overly sensitive to the capacity issue? I also have 3 x 6TB drives I can use for replacement if one of the current drives dies. What's really frustrating is that I'm an accountant and I *know* sunk costs are irrelevant.

Thanks ... Stephen

 

[EAZ1964]

First I would like to correct something: You seem to turn things around.
Your system holds 36.6TB, which is incorrectly reported by the marketing of the disk manufacturers as 42TB.

Then, I you run at SHR, you can swap a 6 tb out for a 16TB, and rebuild.
Repeat this 4 times you should end up with something like 72 TB.
In case you run RAID 5 that will not work

 

[BoosterT]

Thanks for the quick reply ... and yes, you're correct about capacity and the misleading information manufacturers offer.

I know I can do what you suggested as I am running SHR. I was thinking that I wouldn't keep the other 6TB drives in the unit. It's just that it takes a long time to rebuild and to do that 4 times is metaphorically painful. Further, it puts a lot of strain on the remaining drives as it goes through the rebuild process. Maybe I should sell the unit and get another DS1621+ and just rebuild it. Does anyone want to buy a DS1819+ with 8 6TB drives? I'm in Canada.

 

[Deleted member 673]

If all data on your backup DS1819+ is available from original sources, you might consider replacing the 6TB drives with 16TB, configure your new SHR or RAID, and then run a full backup from the original sources. That way, the backups are never in jeopardy of a rebuild failure. Also consider using SHR2 on the new volume. That will provide robust protection against drive failures, as well as flexibility for future expansion.

For what it is worth, here in the U.S., used HDDs sell fairly well on eBay at 35-50% of new price. Used Synology NAS sells very well on Amazon - you may recover as much as 75-80% of new price on a DS...19,20, or 21 model. Ron

 

[esbenvb]

Just curious: Did any of you manage to migrate from a high number of small disks to a low number of large disks?

I have 3x6TB SHR with a 12TB volume
Just bought 2x18TB disks

I wonder if it's possible to replace and rebuild the 6 TB disks one by one, and then convert the RAID5-ish volume to RAID1-ish on the 2 new 18 TB disks?

 

[BoosterT]

I am still waiting for the delivery of the replacement hard drives. FedEx says they're supposed to arrive today ... but they said that yesterday also. It depends on how many drives your NAS can handle. It is possible to replace the 6TB drives one by one, and once they've been replaced. expand the volume. Be aware that if you use SHR, then the NAS will use one of the largest drives as the "redundant" drive. So your available space will be 1 x18 and 2 x 6. I would stick with SHR as it is more flexible than RAID-5. If you can add one or more of the 18tb drives, then do that and then expand. Does that make sense?

Stephen

 

[esbenvb]

Be aware that if you use SHR, then the NAS will use one of the largest drives as the "redundant" drive. So your available space will be 1 x18 and 2 x 6. I would stick with SHR as it is more flexible than RAID-5. If you can add one or more of the 18tb drives, then do that and then expand. Does that make sense?

That's not the issue

I now have a volume that takes up 3 disks. I'm replacing those 3 disks with only 2 disks that are much larger.

And I want to change my current volume to something that takes up 2 disks instead of 3, which should be physically possible now when I install 18TB disk instead of 6 TB

 

[BoosterT]

That's not the issue

I now have a volume that takes up 3 disks. I'm replacing those 3 disks with only 2 disks that are much larger.

And I want to change my current volume to something that takes up 2 disks instead of 3, which should be physically possible now when I install 18TB disk instead of 6 TB

Ok but again it depends on how many drives you can add. If you could physically add both 18TB drives to the NAS but not add them to the existing volume, create a new volume for those two, and copy the material over from the old volume. If not, then you're faced with the same issue I have. My NAS has 8 x 6TB drives. replacing any of the 6TB drives creates the conundrum. I would love to create a new volume and copy the material from original sources, which is best, but that would take forever. If you could do that, you have the three old drives in case anything goes wrong.