All SSD Unraid Server

[Vishesh Gupta]

I am planning on building an all SSD unRaid server. Is it possible to have an all SSD array? 

 

My planned config:

1) 4u, 20 bay hot swap server chassis

2) B550 motherboard with AMD Ryzen 5

3) 32GB DDR 4 ram (Non ECC)

4) Three LSI Sas HBA 9207-8i (6GBps) IT Mode, connecting it to the backplane of the drivebays via mini-sas connector SFF8087.  

5) 10GB TP-Link Switch SFP+ for networking along with 10Gig NIC in both the server & client PC. 

6) Samsung Evo 980 sata SSDs

 

The plan is to install 4 SSDs in the main array with one parity drive initially, and then add additional SSD's to the array as and when needed. 

 

My queries:

1) Does UnRaid support an all SSD array out of the box? In other words, is it just plug and play or do I need to tinker with a few settings? In the past, as per my understanding, auto-trim was absent due to which SSDs were not supported in the main array but only in the cache pools, is it the same case now?

2) Will it be the same process as setting up the array with normal HDD? 

3) What will be the performance / transfer / read - write speeds? As I understand that 10Gig network has a max speed of 1280 MBps, whereas the SAS HBA has a throughout of 6GBps, which translates to 768MBps. However, the max write speed to sata SSD is approx 500 MBps give or take. Assuming that there is no traffic on the network, and the files are being written to the UnRaid server, can I expect 500MBps transfer speed? 

4) Cache pool would be completely unnecessary, correct? OR, having an NVMe SSD (reads / write upto 7000MBps) for cache can help accelerate things, assuming the files are being transferred from the client pc having an NVMe drive with reads / write upto 7000MBps. My question is, does it translate to 875 MBps real world performance? 

 

[JorgeB]

14 minutes ago, Vishesh Gupta said:

1) Does UnRaid support an all SSD array out of the box?

It does, but trim is still not available for array devices, since now there's zfs support recommend creating one or more zfs raidz pools instead, performance will be much better, of course there are also some disadvantages, mostly to do with flexibility, but SSD pools are usually more manageable, since they are typically lower capacity and much faster.

[Vishesh Gupta]

4 minutes ago, JorgeB said:

It does, but trim is still not available for array devices, since now there's zfs support recommend creating one or more zfs raidz pools instead, performance will be much better, of course there are also some disadvantages, mostly to do with flexibility, but SSD pools are usually more manageable, since they are typically lower capacity and much faster.

 

1) So essentially I could have an all SSD array, and not having trim is not the end of the world, right? So it is plug and play just as if I were using HDDs?

2) Can you explain the difference between the main array vs pool? Can I have an SSD pool without the main array?

3) Since ZFS has been recently introduced to UnRaid, there aren't many youtube videos, please excuse me for the noob questions. Correct me if I am wrong, is it the same as setting up ZFS in truenas that is ZFS pool > vDEV (raidZ config, giving 1 parity drive within the vDEV) > Adding a dataset > Creating shares? 

4) Can I add multiple ZFS pools? 

5) If one ZFS pool is doomed for some reason, the other pools wont be affected, right?

6) For my setup, I am planning to have just one vDEV in RaidZ config per ZFS pool, and 4 SSDs per vDEV. This would effectively give me 1 parity drive per pool. 

7) Can you point me to a documentation / video that takes me through the steps of setting up a ZFS pool?

[JorgeB]

15 hours ago, Vishesh Gupta said:

1) So essentially I could have an all SSD array, and not having trim is not the end of the world, right? So it is plug and play just as if I were using HDDs?

Correct.

 

15 hours ago, Vishesh Gupta said:

2) Can you explain the difference between the main array vs pool? Can I have an SSD pool without the main array?

Array uses a dedicated parity and doesn't stripe data for the devices while btrfs/zfs pools stripe data between all devices, each has its own advantages and disadvantages, main ones are detailed here, you can have one or more pools as the main storage but for now at least one array data device must be assigned, but for example an old flash drive can be used to fulfill that requirement.

 

16 hours ago, Vishesh Gupta said:

3) Since ZFS has been recently introduced to UnRaid, there aren't many youtube videos, please excuse me for the noob questions. Correct me if I am wrong, is it the same as setting up ZFS in truenas that is ZFS pool > vDEV (raidZ config, giving 1 parity drive within the vDEV) > Adding a dataset > Creating shares? 

It's similar, you add a new pool, assign the devices, choose pool filesystem and topology, after formatting any new share on zfs will be created as a dataset.

 

16 hours ago, Vishesh Gupta said:

4) Can I add multiple ZFS pools? 

Yes.

 

16 hours ago, Vishesh Gupta said:

5) If one ZFS pool is doomed for some reason, the other pools wont be affected, right?

Right.

 

16 hours ago, Vishesh Gupta said:

6) For my setup, I am planning to have just one vDEV in RaidZ config per ZFS pool, and 4 SSDs per vDEV. This would effectively give me 1 parity drive per pool. 

Yes.

 

16 hours ago, Vishesh Gupta said:

7) Can you point me to a documentation / video that takes me through the steps of setting up a ZFS pool?

This should be a good place to start: