SOLVED Pool of SMR drives? Bad, stupid or retarded idea? - It's retarded and shall be avoided if I got it correctly

[Herr_Merlin]

Hi all,

looking to upgrade one of my private servers to backup family computers and smartphones.
As it turns out that are more than 15TB to backup... Thus I was thinking of using 2.5" SMR drives.. or I have to go to SSD, which will be quite expensive as I am bound to the 2U Rackspace and the free 2.5" SAS 12G slots.

Initially it would be a long write of about 10TB of data.
Smartphone push new data (picture,chats,etc.) when they have new data.
Pool raw size would be about <30TB and initial filled with 10TB from the current system. Additionally about 5TB from other systems, which are not backed up yet.
Data growth is about 1-2TB per year.

Would just be another pool I would add the my TrueNAS.

Currently looking at: Seagate BarraCuda Compute 5TB, 2.5", SATA 6Gb/s (ST5000LM000 which are Shingled Magnetic Recording (SMR), Drive Managed SMR

What are your ideas regarding those disk?
Planned layout:
2x 800GB SAS as Meta Data
2x 480GB SAS as SLOG
3x RAID Z2 of 4 those 5TB disks.

Another option would be going SSD, as I am limited to 2.5" slots. This would lead in way higher costs.
I have the SAS drives and would only need to acquire the HDDs.

If going SSD I would pic the Micron 5210 ION 7.68TB, SATA (MTFDDAK7T6QDE-2AV1ZAB) oder Kingston DC450R Data Center Series Read-Centric SSD 7.68TB, SATA (SEDC450R/7680G). And 6 SSDs as a big RAID Z2 pool, with those SAS SSDs for SLOG added at least.

Another option would be going for just 2.4TB SAS HDD and picking the Seagate Exos E 10E2400 2.4TB, 512e, SAS 12Gb/s (ST2400MM0129).
With those I would need to make use of every free 2.5" slot. As I still have 17 slots free, I would go for with 17" drives and a single big Z3 with one hotspare. That would lead to the same raw capacity but against any sence having 16 drive within one RAID Z...

• Costs for the HDD pool with SMR drives is about: 1500€
• Cost for the SSD pool would be about: 5800€
• Cost for the HDD pool with CMR SAS drives is about: 4300€

Any suggestion or ideas regarding this?

BR

 

[Patrick M. Hausen]

SMR - asking for desaster. Look for the thread started by @Norlig

How would you do this?

Currently I am running: - 4x 4TB drives in RaidZ - 4x 8TB Drives in RaidZ I recently purchased 4x 8TB Drives that I want to replace with the 4TB ones, but I want to set up RaidZ2 with all 8x 8TB Drives. Would I need to copy all my data to a temporary storage location, set up all my drives as a...

www.truenas.com

Remove them from your options, then reconsider those that are left.

After the SMR f'up WD got their act together I think. You could look for WD Red Plus or Pro or whatever they call the documented CMR drives today. I would definitely go shopping (i.e. searching) over a couple of days - "prosumer" SATA drives have highly volatile prices.

 

[Herr_Merlin]

There are no SATA or anything with CMR left with greater than 2TB capacity with 2.5" plus even those lines with CMR are discontinued and replaced with SMR for the 2.5" market.
only go enterprise (SAS) or go SSD...

 

[Johnnie Black]

I had a pool with 8 4TB Seagate SMR for a while, they worked reasonably well performance wise, main issue was the very slow resilvers, if you don't mind that (and the smaller impact in write speed) they are fine, you won't get the timeout issues affecting the WD SMR drives, that's a WD firmware problem.

 

[joeschmuck]

The best advice here is to stay away from SMR drives for ZFS applications.

 

[Herr_Merlin]

so than the final question would be:
- go with the 2.4TB SAS or with the 7,8TB SSDs?
or extend the current pool and store all data there?
Current VM pool are 7x2TB Samsung 860 EVO SATA at RAID Z1.. would deliver the need.. but would be the cheapest with just below <3000€

 

[elorimer]

3,000 euro?? Adopt me.

I would trash whatever is limiting you to 2.5 inch and go with 3.5 inch. It's just backup, right? Heck, I would focus on something off-site to boot.

 

[Herr_Merlin]

Na I only have 2U at the datacenter not changing that nor the host.
Question is going for the cheap option with just adding more 2TB or going for expensive and have space for further upgrades and going for the 7TB SSDs

 

[Patrick M. Hausen]

We have 24x 3.5" in 2U:

6028R-E1CR24L with Part List | SuperStorage | Products | Super Micro Computer, Inc.

The SSG-6028R-E1CR24L multi-processor system is optimized for extreme large in-memory computing, and/or mission critical apps with maximum configurability and scalability.

www.supermicro.com

 

[Herr_Merlin]

Thats now going a bit off topic.
Server is an Intel system with either 12x3.5 or 24x2.5. I have both bays so I could swap..
Has 1x Vega 56, 1x gPro something GPU, 1x Tesla K20X.. 2x xeon e5-2680v2 and 384gb of memory.. 2x 480gb sata ssd for host is (esxi) ..
That's my personal private all in one box.
Having a TrueNAS VM for VM storage with 7x 2TB Samsung evo 860 in raid z1..
An upgrade would be quite pricey..

As I got the unit with the CPUs, memory and both bays for about 400e..
Adding about 300e for the gpus
Thus a new server would cost way more than and the savings of 3.5 cheaper disk wouldn't be so high

 

[Herr_Merlin]

marked this one as solved. as the conclusion is that it's retarded.