Has anyone upgraded their parity drive from 4TB to 8TB and has been successful? What brand 4TB did you come from and what 8TB did you end up buying and why? I want to make that change, but I would cost me quite a bit. I'm currently sitting around 42TB with %74 full.  The SSD market to catch up since those manufactures will milk every penny  out of the market for well over a few years so that's out of the questions, but I'm alright with that using mechanicals for a while.

 

Maybe I'm missing something (so please pardon me here) but what would make upgrading from 4TB to 8TB unsuccessful?

I thought it's a matter of removing the old parity, add the new parity, sync parity, done.

Maybe I'm missing something (so please pardon me here) but what would make upgrading from 4TB to 8TB unsuccessful?

I thought it's a matter of removing the old parity, add the new parity, sync parity, done.

 

Because every action I do now will affect what I do later on. If I keep the 4TB drive as a parity, then that's the highest drive size I can get and would probably save some money. If I buy a more expensive 8TB parity, I know in my mind I'll end up spending more money on a couple 8TB "just for the heck of it". And I can even release a couple 2TB drives.

 

I try to think ahead on what I'm going to do, but certainly can't predict the future.

Has anyone upgraded their parity drive from 4TB to 8TB and has been successful? What brand 4TB did you come from and what 8TB did you end up buying and why? I want to make that change, but I would cost me quite a bit. I'm currently sitting around 42TB with %74 full.  The SSD market to catch up since those manufactures will milk every penny  out of the market for well over a few years so that's out of the questions, but I'm alright with that using mechanicals for a while.

 

I have my first parity drive on 8TB, the second one is stil 6TB..  Ony my backup system I only have 1 parity drive, its an 8Tb..

 

They work great..

 

Btw: the reason for the second parity drive still beiing 6TB is that I do not need more drive space at the moment... Whenever I need more space I buy the largest available drive and make that my parity drive, then promote the old parity to a data drive..

I would do what Hellmonder do. If I run out of space, I just buy the largest (affordable + available) HDD plop it as the new parity and use the old parity as data drive. There's an added benefit that (if the new parity is larger than your old parity) you will be utilizing the faster end of the new parity.

 

So I would say there's really no reason not to get an 8TB. You can simply preclear the 8TB, unplug the old 4TB, plug the 8TB and rebuild parity (but I'm sure you know that). If nothing wrong then done.

 

I would say though, wait a couple more months for the 10TB model to push prices of all other models down.

There's an added benefit that (if the new parity is larger than your old parity) you will be utilizing the faster end of the new parity.

 

 

So writes to the array potentially could be faster then??

So writes to the array potentially could be faster then??

Keyword is potential 

... There's an added benefit that (if the new parity is larger than your old parity) you will be utilizing the faster end of the new parity.

 

It's true that writes will avoid the inner cylinders if the parity drive is larger than all others; but when you do a parity sync or parity check the entire parity drive is still used, so there's no benefit with regards to those operations. 

As for which 8TB drive to use ...

 

=> Many folks have used the shingled Seagates without issue; but these could have significant performance deterioration if your useage pattern was to "hit" the point where the drive had to clear the persistent cache.  While these drives are fine for most data drive usage patterns; I'd be inclined to play it safe and use a standard PMR drive for the parity drive(s).

 

=>  I've been VERY happy with the 8TB WD Reds, which are excellent, helium-filled units that perform very well.

 

=>  The newer Seagate units, as well as the WD Red Pro, are 7200 rpm drives, so these should have even better performance, but I have not personally used any of them.    I'm happy enough with the performance of the Reds, and don't want the extra power consumption and heat generated by 7200 rpm drives, so if I was buying more drives of this size I'd stay with the Reds.

 

 

 

As for which 8TB drive to use ...

 

=> Many folks have used the shingled Seagates without issue; but these could have significant performance deterioration if your useage pattern was to "hit" the point where the drive had to clear the persistent cache.  While these drives are fine for most data drive usage patterns; I'd be inclined to play it safe and use a standard PMR drive for the parity drive(s).

 

=>  I've been VERY happy with the 8TB WD Reds, which are excellent, helium-filled units that perform very well.

 

=>  The newer Seagate units, as well as the WD Red Pro, are 7200 rpm drives, so these should have even better performance, but I have not personally used any of them.    I'm happy enough with the performance of the Reds, and don't want the extra power consumption and heat generated by 7200 rpm drives, so if I was buying more drives of this size I'd stay with the Reds.

 

I am using the 8TB shingled as DATA drives in my backup system, for parity I use 8TB Seagate's (non shingled desktop drives).. For some reason I think using the shingled ones as parity drives is not a good idea.. Might be feeling only... The ST's are behaving fine, for the rest I am using mostly WD RED's..

There's a fairly extensive discussion of the shingled Seagate drives in UnRAID here:

https://lime-technology.com/forum/index.php?topic=39526.0

 

Basically, the mitigations that Seagate implemented on these drives seem to work very well for MOST use cases in UnRAID, and the performance is fine.  What IS true is that if you get outside those bounds, the performance degradation is SEVERE ... it will eventually recover as the drive empties the persistent cache; but it's not something you'd really want to encounter.

 

I think the safest thing to do is, as Helmonder does, limit any use of the shingled drives to data drives; and use standard PMR units for the parity drive(s).    As I noted above, I'm a big fan of the 8TB WD Reds for this purpose; although the new 10TB Seagate Ironwolf units are very attractive ... and are reportedly also helium sealed (like the 8TB Reds).