932X - add SSDs for Qtier?

[RobAinscough]

I currently have 5 HDDs at RAID 5 and 2 SSDs at RAID 0 using Qtier. I'd like to add 2 more SSDs and use RAID 5 for all 4 SSDs. Will I have any issues with data loss from the 5X HDDs? Is the process just a matter of add the SSDs and wipe and reset to RAID 5?

Cheers, Rob.

[dolbyman]

well raid0 for qtier is basically a ticking timebomb ..so good for you switching to raid5

remove the current tier (if you have enough space on the hdds for the tiered data)
wipe the now detatched qtier volume
insert two more ssd's and attach the raid5 tier

[RobAinscough]

remove the current tier (if you have enough space on the hdds for the tiered data)

Not sure what you mean by this? I thought my SSDs assigned to Qtier were just duplicate files for quick access? If not, how do I go about moving the Qtier SSD data to my HDD?

I have about 10GB free space on the HDDs and the Qtier is only about 500GB right now.

Cheers, Rob.

[storageman]

Of course they are not duplicates, a file's blocks can sit in HDD and SSD tier if hot blocks are being moved upwards.
The HDD + SSD tiers are one shared volumes.
Remove Qtier is only available in 4.4.1 and above

Maybe watch this
https://www.youtube.com/watch?v=y0pRpG43ZX8


Caching is more like a temporary work area but completely different

[RobAinscough]

Thanks for the link, I watched the video, it was unfortunately not very helpful. For example they don't actually show you how to bring up the "Ultra-High Speed Tier Removal Wizard" (I did eventually figure it out). I also found the accents to be very difficult to hear/understand, no offense intended as the two speakers aren't native English, it's just that I have Tinnitus and even with my noise cancelling headphones it was very difficult to hear/understand.

Apparently my Ultra-High Speed Tier doesn't have enough available space to be "removed". Here is are some images of my setup:



and the "red" message indicating I don't have enough space to remove the Ultra-High Speed Tier:



I must admit, I'm not sure how useful this new feature in 4.4.1 really is ... my expectation is the "Ultra-High Speed Tier Removal Wizard" would be smart enough to copy the data TO my HDD RAID 5 (RAID Group 2) but apparently it can't and is limited to SSD RAID Group 1 only. This just seems completely useless as a "feature" as I would expect that when people want to upgrade their SSDs it's because they've run out of or close to running out of capacity. Did QNAP development team sorta "miss the boat" on practical usage with this feature?

Anyway, it seems I'm going to have to back everything up once again to another storage device as I have no idea what is and isn't on the Qtier SSD RAID group.

Cheers, Rob.

[dolbyman]

if you remove the high speed tier, your storage tier has to have enough space to take all the data from the removed tier, not quite sure why this isn't clear

you said you only have 10GB free on the spinning drives .. how are 1TB supposed to fit on 10GB ?

[RobAinscough]

You lost me there, per image above ... I have 14.52TB available space? This is why I don't understand why I can't remove the Ultra-High Speed Tier which is only 912GB?

Oh, sorry I made a mistake in the 10GB space comment, seem my snapshot images.

Cheers, Rob.

[dolbyman]

how much space is actually free on the volume ? the volume occupies 14.52TB of the pool .. but is it empty or full ?

[RobAinscough]

3.83 TB used so just over 10 TB free



Not being able to use this free space because it's on a different RAID group seems rather limiting functionality.

Cheers, Rob.

[dolbyman]

just went to Step1 myself, .. apparently QTIER removal needs available pool space, not volume space

so you could shrink your volume a bit, so there is enough space on the pool to drop the SSD group

https://forum.qnap.com/download/file.php?id=28680&mode=view

[RobAinscough]

Ah, ok so shrink the volume, do the Qtier removal, add the two new SSDs and then add Qtier and then expand the volume back to where it was before?

Cheers, Rob.

[dolbyman]

I think that should work ... never did qtier removal myself .. sorry

[RobAinscough]

Well I got lucky, everything seemed to have worked out well.

1. Shrink Volume by 2TB
2. Remove Qtier and wait
3. Installed 2 more SSDs
4. "Upgrade to Qtier"
5. Set SSDs to RAID 5 for QTier
6. Wait for sync to complete
7. Expand volume back to max
8. Wait for expand to complete

All my data still intact. So it does work, just a little different than I expected. I must admit I do love the features of this 932X and it's very responsive/fast even on slower 1Gbps LAN ... even have it on it's own dedicated UPS now.

Thanks for the assistance all.

Cheers, Rob.