USB DOM (disk on module) in 2022?

[gvkhna]

Hey there, 

 

I setup my first unraid about a month and a half back, with a fresh San disk usb. It just died, admittedly I did a lot of searching for high quality usb sticks but couldn’t find any discernible difference, they all seem cheap overall. 
 

Especially the advice to remain on usb 2.0 seems almost outdated at this point, usb 2 drives are relatively hard to find compared to usb 3.0. 
 

After the recent Linus video about USB DOM, I started looking into it. I bought one because I really don’t want to deal with drive failure but I’m trying to harden my system from downtime and am considering a backup solution running in the server, which is inconvenient to take out of the rack and service. 
 

I was reading some Reddit threads, someone mentioned they don’t use usb DOMs anymore after their company had a lot of failures, and switched to ssds for boot drives. 
 

The costs are the same at this point, you can get a low capacity nvme ssd for  $50-80, about the same price as a DOM. Also they’re really readily available and mine have been working very reliably for years. 

I’m considering just switching a 500gb nvme to my boot drive, and upgrading the computer it’s in to a 1tb because I could use the additional space. 

Can an nvme be used as unraid boot, has GUID? And is there really any updates to the advice about usb flash in 2022? This is inconvenient to boot from usb because usb drives are quite hit or Miss, and changing them requires downtime which I’m heavily trying to avoid. 
 

im running some business applications on my unraid so I’m trying to have some semblance of reliability. Any thoughts?

[Squid]

Flash drives have a bad rep, but in practice they're one of the most reliable components in any given server.

 

SSDs / nvme are not supported as boot media.  

 

Sandisk though is also not currently recommended as they are being counterfeited and sold by major retailers https://forums.unraid.net/topic/119052-psa-on-sandisk-usbs/   Your mileage may vary though.

 

Avoid small form factor sticks as they run extremely hot, and heat is the enemy of any electronics

 

The old adage of USB2 drive in USB2 port is becoming less recommended now as the later kernel versions are handling things much better.

 

My 2 main servers run off of 10 year old sticks (USB2)  My test server runs off of a 3 year old USB3 stick.  No issues have ever happened to any of them.

 

Actual downtime though in a flash failure is minimal (minutes) -> set up a new flash drive and transfer the registration using the automated method of doing this.  Only if the automated method fails do you need to enlist the services of support, in which case I believe their average response time now is about 20 minutes through working hours 7 days a week.  

 

[primeval_god]

40 minutes ago, gvkhna said:

Can an nvme be used as unraid boot, has GUID?

No a USB drive is still required to boot unRAID.

 

40 minutes ago, gvkhna said:

And is there really any updates to the advice about usb flash in 2022?

As far as i know the recommendations have not changed. USB 2.0 is still preferred. The reasons that i am aware of are that some (possibly older now) motherboards did not like to boot correctly from their USB3 controllers whereas USB2 worked fine. Additionally the controllers in USB3 tend to run hotter than USB2, and there is some concern as to how that effects life longterm especially for physically small thumbdrives.

 

40 minutes ago, gvkhna said:

I setup my first unraid about a month and a half back, with a fresh San disk usb.

There is a PSA posted in the Announcements forum about Sandisk usb drives purchased from various vendors in recent months.

 

40 minutes ago, gvkhna said:

im running some business applications on my unraid so I’m trying to have some semblance of reliability. Any thoughts?

The USB drive i have has been running very reliably for 5+ years now. That said my personal opinion, which has nothing to do with the flash aspect of unRAID, is that unRAID should not be used for business purposes, due primarily to the robustness of its security, slow patch cycles, and limited support options. For a home NAS its a Rockstar.

 

Edit: Looks like Squid got here while i was still typing.

Edited May 2, 2022 by primeval_god

[gvkhna]

Ok so I will try the USB DOM. I had a usb header to usb plug adapter but it kept falling out so I ended up returning it. 
 

Due to clearance in the front and rear of the rack I can’t have a usb drive sticking out. 
 

Against rec. I did end up getting the tiny one for that reason, guess the PSA is for good reason. 
 

I will try the USB dom and hope for the best, that seems to be the best solution for my use case. 
 

I was also looking at an exotic pcie dom, because I have a spare x1 pci bus available. Any idea if that will work, I don’t want to use that though because it’s so rare but curious if it would work.

[whipdancer]

In the 10 years I've been using unRaid, I've had at least a dozen drive failures (HD & SSD) - but no issues with the thumb drives that I started with.

[trurl]

30 minutes ago, gvkhna said:

I will try the USB dom...I was also looking at an exotic pcie dom

Probably neither will have GUID needed for licensing.

[Squid]

3 minutes ago, trurl said:

Probably neither will have GUID needed for licensing.

I hope it does since Linus stated they'd be good for Unraid

[JonathanM]

1 hour ago, gvkhna said:

Due to clearance in the front and rear of the rack I can’t have a usb drive sticking out. 

For multiple reasons it's preferred to have the stick inside the case, typically using motherboard header adapters if the motherboard doesn't have internal USB headers. Many server boards have native USB connectors on the motherboard inside the case.

[SpencerJ]

24 minutes ago, JonathanM said:

For multiple reasons it's preferred to have the stick inside the case, typically using motherboard header adapters if the motherboard doesn't have internal USB headers. Many server boards have native USB connectors on the motherboard inside the case.

Sounds like a new poll topic: Are you an Innie or an Outie? 😜

[gvkhna]

5 hours ago, JonathanM said:

For multiple reasons it's preferred to have the stick inside the case, typically using motherboard header adapters if the motherboard doesn't have internal USB headers. Many server boards have native USB connectors on the motherboard inside the case.

This is a good point, many motherboards do have USB’s inside, but most of them are unused, as they will probably NetBoot. 
 

the general lack of options is my gripe with the situation, having to have something like a yubikey or a hardware pcie card for licensing is relatively fine, but constraining boot options makes it more inconvenient for just administrating your setup however makes sense to you IMHO. I guess it’s a small issue but something like a yubikey for licensing, and allowing booting off of whatever makes sense to you (even netbooting) would be great!

[JonathanM]

2 minutes ago, gvkhna said:

have something like a yubikey or a hardware pcie card for licensing

What would something like that cost per instance? Some people already gripe about the cost of Unraid, so any realistic option must be rather low cost.

[gvkhna]

1 hour ago, JonathanM said:

What would something like that cost per instance? Some people already gripe about the cost of Unraid, so any realistic option must be rather low cost.

Fair point, I just looked and yubikeys to my surprise cost almost $50, but the sheer longevity considering their simplicity might be worth it. 

[ChatNoir]

Cost of the key, plus cost and complexity of shipping worldwide.  🤪

This would require probably several more LT employees and a warehouse ; or realistically a subcontractor. Probably one for each large bodymass.

The added cost would be what, 50 to 100$ ?

 

3 hours ago, gvkhna said:

but the sheer longevity

Are Yubikeys really that more reliable ?

 

The current flashdrive system is one of the many imperfect possible solutions to a very complex problem.

[gvkhna]

*sigh* I guess so. It looks like the generic FIDO2 keys can be had on Amazon for $22. Not a bad option, the problem flash has is yield, so most usb flash keys are bargain bin flash. I doubt something as simple as a FIDO key has such issues. 
 

[gvkhna]

Installed the USB DOM, works great.

[garrett hamonic]

On 5/5/2022 at 3:24 PM, gvkhna said:

Installed the USB DOM, works great.

Can you show us which USB DOM you decided on. 

[gvkhna]

I looked but can't find the receipt for the one I purchased. If i remember correctly I ended up going with the exact model number mentioned in the LTT video by Anthony. It was pricey but haven't had any issues so well worth the cost if it lasts many years which I'm hoping.

 

There's a good reddit thread on the topic with some more info.

 

 

[FlyingTexan]

Necro posting here but how did you setup the DOM? Did you use a desktop first then move it to your unraid? Or is it possible to install it and go into unraid and have everything transfer over?

[gvkhna]

I used another PC yes, put it in the motherboard of a server running windows. Did the install. Took it out and put it into the unraid server. Still working!