Out of Space on DS918+ ARPL X99 ALL FLASH Build. Need help deciding how to add Storage to massive SHR

[Captainfingerbang]

I knew this day would come, I've been dreading it.

I'm out of space on DS918+ ARPL Baremetal DSM 7.1.1-42962 Update 4 

In SHR i have 3- 1TB SSD's and 5-2tb SSD's  Total=8 2.5 inch sata SSD's. Gives me a little over 10GB usable. 

Not thinking it through, and being lazy, i bought a 4tb SSD for $175 @ Newegg thats in the mail. (bottom pic)

 

So i just ran raid calc and it SAYS the 4tb will do me just the same good as a 2tb! No difference then adding a 2tb.?...

Understandable if this were 6.2. I reread Synology website for adding SSD to 7.1+  and it says I CAN add 2tb or larger (since 2tb was biggest)

So there's what Synology is telling me for 7.1 which is different then the raid calc. Which to trust?

So how many gb's  will i really get if i add this 4tb ssd to my system? Can i expect the increase to 13gb or 15gb?

 

 

 

 

p.s. i have a couple of extra (2) pcie 3.0 m.2 ssds @ 1tb each, i'll also like to add those eventually, for storage

 

 

 

 

 

 

 

 

 

 

 

Edited April 16, 2023 by Captainfingerbang

[dj_nsk]

2 часа назад, Captainfingerbang сказал:

So i just ran raid calc and it SAYS the 4tb will do me just the same good as a 2tb! No difference then adding a 2tb.?

Yes. It will start using all 4Tb after you add at least one more disk of at least 4Tb.

2 часа назад, Captainfingerbang сказал:

it says I CAN add 2tb or larger (since 2tb was biggest)  So there's what Synology is telling me for 7.1 which is different then the raid calc. Which to trust?

That's right - you can add a 4Tb disk, but only 2tb of them will be used so far.

 

2 часа назад, Captainfingerbang сказал:

So how many gb's will i really get if i add this 4tb ssd to my system? Can i expect the increase to 13gb or 15gb?

Much better! you will get 13Tb (not gb  )!

 

2 часа назад, Captainfingerbang сказал:

i have a couple of extra (2) pcie 3.0 m.2 ssds @ 1tb each, i'll also like to add those eventually, for storage

No, it isn't possible to add a disk less than 2Tb to the same resource pool right now.  And if you add 4Tb, then the next disk should be at least 4Tb.

But you can create new JBOD resource pool from disks 1+1+4 =6 TB for storing data that doesn't require crash protection.

 

[Captainfingerbang]

12 hours ago, dj_nsk said:

Yes. It will start using all 4Tb after you add at least one more disk of at least 4Tb.

That's right - you can add a 4Tb disk, but only 2tb of them will be used so far.

 

Much better! you will get 13Tb (not gb  )!

 

No, it isn't possible to add a disk less than 2Tb to the same resource pool right now.  And if you add 4Tb, then the next disk should be at least 4Tb.

But you can create new JBOD resource pool from disks 1+1+4 =6 TB for storing data that doesn't require crash protection.

 

What I was getting at is, aren't the rules different now with 7.1? like possibly I will get 15tb?

 

why is adding those nvme storage not going to work? I already have 1tb drives in this, I cannot add more 1tb drives?

[dj_nsk]

1 час назад, Captainfingerbang сказал:

What I was getting at is, aren't the rules different now with 7.1? like possibly I will get 15tb?

 

why is adding those nvme storage not going to work? I already have 1tb drives in this, I cannot add more 1tb drives?

1. no. You'll get 13Tb

2. Sorry my mistake (I confused it with the disk replacement situation). At any given time, the rule applies: "For RAID 5, RAID 6, and RAID F1: The capacity of the drive you wish to add must be equal to or larger than the smallest drive in the storage pool. For example, if your volume is composed of three drives – 2 TB, 1.5 TB, and 1 TB respectively – then the capacity of the new drive must be at least 1 TB." - so You can add 1Tb.

But be careful! It is impossible to reduce the number of disks included in RAID SHR in the future (if you want to) without deleting the resource pool.

[Trabalhador Anonimo]

Any raid system will use the smallest disk as reference for raid capacity. if you put this 4Tb on a raid with 1Tb disks, only 1 TB of 4 Tb will be used. To get all TB used, you have to replace all SSD for the same size.

You can start replacing 1Tb at a time and rebuild your raid and after replace all 3, you will get more space.

[dj_nsk]

8 часов назад, Trabalhador Anonimo сказал:

Any raid system will use the smallest disk as reference for raid capacity. if you put this 4Tb on a raid with 1Tb disks, only 1 TB of 4 Tb will be used. To get all TB used, you have to replace all SSD for the same size.

You can start replacing 1Tb at a time and rebuild your raid and after replace all 3, you will get more space.

Wrong! SHR allows you to add disks of different sizes to RAID - see here.

[Trabalhador Anonimo]

26 minutes ago, dj_nsk said:

Wrong! SHR allows you to add disks of different sizes to RAID - see here.

 

You had misunderstood the concept. You have to look into colors on the same line. Look at dark blue line, only 1tb is used. On disks of 2TB you can use the rest of thew space to create another volume and so on.

[dj_nsk]

3 минуты назад, Trabalhador Anonimo сказал:

 

You had misunderstood the concept. You have to look into colors on the same line. Look at dark blue line, only 1tb is used. On disks of 2TB you can use the rest of thew space to create another volume and so on.

no, You're wrong, read more carefully

[Trabalhador Anonimo]

Lets put an end on SHR and disk spaces. SHR get the smallest hdd size and creates a space named "chunk" on every bigger disk. I.E: if you have a raid 5 with 1x 1tb and 2x2TG, SHR will create 2 "chaunks" in each 2TB disks. This means you will have 5 spaces of 1TB. SHR will split your data into the "chuncks" as much equally as possible. If your smallest disk is full, SHR will continue to put your data on the other disks. This means your raid protections will fail because the information will not be split as it should be.

Back to what I said before, replace your smallest disk (1tb), one at a time, with 2tb and rebuild your raid. This will give you more space and security.

Edited April 18, 2023 by Trabalhador Anonimo
Correct some type mistakes.

[dj_nsk]

1 час назад, Trabalhador Anonimo сказал:

If your smallest disk is full, SHR will continue to put your data on the other disks. This means your raid protections will fail because the information will not be split as it should be.

You have a very strange understanding of the article I mentioned about SHR (read for example: "Unlike classic RAID, SHR divides each drive's storage space into smaller chunks and creates additional redundant storage"). Try to check it in the calculator (I filled in the disk information there for example from @Captainfingerbang) and you will be surprised.

There is no threat that "raid protections will fail"