Intro: new Unraid setup

[cktulsa]

Hello community,

 

I found out about Unraid just a couple of weeks ago. I have a lengthy IT background (back to TRS80 Model I days) and I've found myself wanting to beef up my home IT infrastructure lately. I'd thought I would build a FreeNAS box and maybe run Nextcloud in a Docker container, but then I discovered Unraid. I've been tinkering with it ever since, most of the time on a totally unsuitable ShuttlePC I had laying around. But it gave me the chance to gain some understanding of Unraid before diving in.

 

A few days ago I ran across a couple of older IBM servers for practically nothing, and decided to try out building up an Unraid instance on one of them. My goals for this build are pretty minimal. I'm not that into digital media and plan to use the box primarily as a file server, as well as running some Docker containers and maybe a Linux VM or two. I'm not too interested at this point in Windows or any GPU pass-through.

 

Basic specs on the servers:

 

IBM System x3500 (huge, heavy tower case)

2 x Xeon x5450 - quad-core, 3.0 GHz, 12MB L2 cache (VT-x but no VT-d)

48 GB DDR2 ECC RAM

ServeRAID 8k SAS/SATA raid controller w/ 8-drive hot-swap backplane

Dual 835 watt power supplies

Two 64-bit PCI-X slots, three PCI-Express slots

Four Gigabit ethernet ports

 

I quickly discovered that the RAID card can handle only up to 2TB drives, so I bought four Western Digital Red NAS drives - the 5400 RPM ,256MB cache version. I also discovered that the card has no true pass-through mode (as far as I can tell). I set up the four drives as individual "volumes" using the RAID config utility, and Unraid was able to see them. I set up one as a parity drive and the other three as data drives giving me 6TB, which is more than enough for my current needs. I'm not waiting for the initial parity sync, which says it will take a long time (like 6 hours).

 

I thought at some point I may buy two 500GB SSDs and a PCI Express SATA controller for Unraid cache.

 

I suppose I'll buy an Unraid license if things go well, and sometime later might consider building up a more modern hardware platform for Unraid.

 

Any thoughts or suggestions would be appreciated.

 

Thanks.

Curt

 

 

 

 

 

[trurl]

5 minutes ago, cktulsa said:

Any thoughts or suggestions would be appreciated.

Get a different controller.

[cktulsa]

10 minutes ago, trurl said:

Get a different controller.

That would probably mean a different server. There's no good way to mount drives in this chassis without using the hot-swap backplane.

 

What's the risk with this controller as-is? 

 

Thanks.

Curt

 

[JonathanM]

13 hours ago, cktulsa said:

What's the risk with this controller as-is?

You are foregoing some of the main selling points of unraid as a NAS, specifically the ability to move your drives to new hardware without reformatting or at the very least manually figuring out which volume is assigned to which logical drive slot in unraid. Also, the native ability of unraid to monitor the health of the drives is not likely to work, so you may not have good warnings of impending drive failure.

 

There may well be other consequences which may not become obvious until later, possibly after a drive failure, which could make recovery much more challenging.

 

The normal recommendation is to be sure you keep current backups of any data you don't want to lose, because Unraid (or any RAID) only offers protection from drive failure. Data deletion or corruption from external sources can't be protected by RAID or Unraid. In the case of using a controller that doesn't allow Unraid direct access to the drives, you are also losing some of the protections against drive failure.

[cktulsa]

Thanks @jonathanm - the advice is much appreciated and makes sense. Given that I can't afford to go build a better Unraid box right now, and I can't easily run a different controller in this chassis, I am now leaning toward leaving Unraid for another time. I could load these servers up with ESXi and run Nextcloud in a Docker container, and take advantage of the RAID I already have. 

 

Sometimes Unraid just may not be the best option.

 

Curt

 

 

 

[trurl]

38 minutes ago, cktulsa said:

Sometimes Unraid just may not be the best option.

That may be true. Just thought I would mention the main advantages of the Unraid design as opposed to RAID in case you weren't completely aware of them.

1. You can mix disks of different sizes in the array.
2. You can easily add or replace a disk without rebuilding the entire array.
3. Each disk is independent and can be read on any linux.

[cktulsa]

27 minutes ago, trurl said:

That may be true. Just thought I would mention the main advantages of the Unraid design as opposed to RAID in case you weren't completely aware of them.

1. You can mix disks of different sizes in the array.
2. You can easily add or replace a disk without rebuilding the entire array.
3. Each disk is independent and can be read on any linux.

 

I am definitely on board with these advantages, and I'd really like to run it. But if it's not advisable to run it on the hardware I have, I'll have to go another route. 

 

If anyone thinks it would be better to run Unraid on this hardware than to go with hardware RAID (probably RAID 6), I'd be very interested in hearing about that!

 

Curt

 

[cktulsa]

OK, I made some interesting progress on this. I got a bit more serious about disassembling one of the servers, and found that I can remove the entire SAS backplane. This frees up the space to run cabling from a PCI-E controller card to a set of SATA drives mounted in the original caddies. Thinking I will follow everyone's advice and ditch the old ServeRAID 8x controller for one that's better for Unraid and keep pushing forward on a build.

 

So now I just need to source a truly appropriate controller card that will work well for my scenario. I've read some forum threads on this, and I found this list: https://wiki.unraid.net/Hardware_Compatibility#PCI_SATA_Controllers

 

My slots are labeled PCI-E x8 and one has a (x4) next to that. I assume these are PCI-E 1.0. Given all that, any obvious recommendations for a good controller card that's easy to get and works out of the box?

 

Thanks!

Curt

 

[itimpi]

Be wary of that list - it is probably badly out-of-date

 

You do NOT want to use any controller based on a Marvel chipset - they do not play well with the latest Linux kernels.   You also do not want to use pure RAID controllers.  What IS recommended is controllers based on the LSI chipset (and compatibles) and running in IT mode (not RAID mode).  Older version of these do not support trim operations and so are not suitable for use with SSDs (although they are fine with HDD).

[cktulsa]

18 minutes ago, itimpi said:

Be wary of that list - it is probably badly out-of-date

 

You do NOT want to use any controller based on a Marvel chipset - they do not play well with the latest Linux kernels.   You also do not want to use pure RAID controllers.  What IS recommended is controllers based on the LSI chipset (and compatibles) and running in IT mode (not RAID mode).  Older version of these do not support trim operations and so are not suitable for use with SSDs (although they are fine with HDD).

Thanks @itimpi ! I'm thinking of going with the LSI 9211-8i : https://smile.amazon.com/SAS9211-8I-8PORT-Int-Sata-Pcie/dp/B002RL8I7M

 

Plus a set of SFF-8087 to SATA Forward Breakout cables. 

 

I can probably handle the flashing to IT mode since there's instructions here (hopefully I can find the most current ones).

 

Curt

 

[mrbilky]

1 hour ago, cktulsa said:

Thanks @itimpi ! I'm thinking of going with the LSI 9211-8i : https://smile.amazon.com/SAS9211-8I-8PORT-Int-Sata-Pcie/dp/B002RL8I7M

 

Plus a set of SFF-8087 to SATA Forward Breakout cables. 

 

I can probably handle the flashing to IT mode since there's instructions here (hopefully I can find the most current ones).

 

Curt

 

I have 2 of these from this vendor they were plug and play with both my unRAID boxes one home built the other a Dell R710 and seem to be a bit cheaper than that card listed:

 

https://www.ebay.com/itm/Dell-H310-6Gbps-SAS-HBA-w-LSI-9211-8i-P20-IT-Mode-for-ZFS-FreeNAS-unRAID/162834659601?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

[cktulsa]

@mrbilky thanks for the great info!

 

Curt

 

[cktulsa]

Quick update:

 

I ordered and received a boxed 9211-8i, and I realized I could cable that thing right up to the hot-swap SAS backplanes in this IBM server. No need for the forward breakout cables. All I needed was two SFF-8087 to SFF-8087 cables that were pretty long, and I was good.

 

Before cabling up the drives I installed the card and followed these instructions to flash it to IT mode:

https://nguvu.org/freenas/Convert-LSI-HBA-card-to-IT-mode/

 

That part was easy. Then I cabled up the backplanes to the card and booted the server. Unraid can see all four WD SATA 2TB drives and it's now doing a parity sync.

 

So now I have all four drives directly accessed by Unraid and no more ServeRAID card in the way. Thanks for everyone's advice!

 

Curt