How to make use of external drives with TrueNAS SCALE?

[dffvb]

Hi there, I have a couple of external hard drives which I would like to use in an easy way as cold backup for my TrueNAS SCALE. Are you aware of any options?

I tried a replication job, under "Data Protection" however when I tried to disconnect, the test server lost the network conenction... (even after deleting the replication job).

Any ideas?

 

[copz1998]

Hi there, I have a couple of external hard drives which I would like to use in an easy way as cold backup for my TrueNAS SCALE. Are you aware of any options?

I tried a replication job, under "Data Protection" however when I tried to disconnect, the test server lost the network conenction... (even after deleting the replication job).

Any ideas?

Did you figure it out yet? I have a fresh TrueNAS Scale install and want to use a 5TB SSD external drive as a backup. I have been unable to find clear documentation on a "howto" for setting up a USB drive.
Thanks!

 

[sretalla]

unable to find clear documentation on a "howto" for setting up a USB drive

It's not hard... plug in drive, go through the normal process to set up a pool.

Set up a replication task to do the backups you want, but don't schedule it too frequently (see below).

Problem: if you do anything other than occasional backups to that pool, you'll wind up burning out either the USB to SATA controller or the USB controller after a relatively short amount of time (months, not years) due to the intensity of transaction group IO.

 

[copz1998]

Thank you, Sretalla,
When I go to create a pool, it only gives me a stripe option. It is a single drive, so a strip format is not appropriate. Should I try to format the USB drive in a console? Which format is preferred?

Thanks again.

 

[sretalla]

For a single disk, a stripe is the only option.

 

[alugowski]

As far as TrueNAS is concerned there is zero difference between USB and internal devices. You plug them in and create a pool. If you want to remove it then you must export the pool. Replication is identical to any other replication.

I have a USB hard drive that has nightly replications of the stuff I really care about from my main RAIDz pool, it works fine. I have another NUC-style device that has a main pool from two mirrored USB hard drives. Works great despite what the naysayers say.

The "burn up" comments are valid ONLY for USB sticks. USB hard drives and USB SSDs don't burn up any faster than internal versions.

 

[copz1998]

Thank you! All working well.

 

[sretalla]

The "burn up" comments are valid ONLY for USB sticks. USB hard drives and USB SSDs don't burn up any faster than internal versions.

Not correct. USB controllers involved in data pool disks will likely fail at some point. You can get away with "infrequently used" pools like backups, but require a little luck to do so in the very long term.

a main pool from two mirrored USB hard drives. Works great despite what the naysayers say.

Mirrors aren't as bad as RAIDZ, but I wish you luck with that, you'll need it.

 

[ChrisRJ]

Mirrors aren't as bad as RAIDZ, but I wish you luck with that, you'll need it.

It is fascinating to see how "capable" people are to ignore statistics. The argument is the same like me saying that I never needed my car seat belt in more than 30 years of driving. That is anecdotal and obviously does not say anything about the usefulness (or theoretically lack thereof) of seat belts.

Of course I am happy if someone has so far(!) not run into problems with USB disks. But to claim that it is a fully reliable and working approach, based solely on personal experience with a single system, is irresponsible at best.

 

[alugowski]

It is fascinating to see how "capable" people are to ignore statistics. The argument is the same like me saying that I never needed my car seat belt in more than 30 years of driving. That is anecdotal and obviously does not say anything about the usefulness (or theoretically lack thereof) of seat belts.

Of course I am happy if someone has so far(!) not run into problems with USB disks. But to claim that it is a fully reliable and working approach, based solely on personal experience with a single system, is irresponsible at best.

I offered my anecdote to show I'm putting my money where my mouth is.

I said USB and internal are equivalent as far as TrueNAS is concerned, i.e. from a managing pools and drives point of view. That is absolutely true.

Of course there are lots of issues you can hit with USB that you won't with SATA, NVMe or SAS. Yes some controllers don't support SMART. Yes some controllers are buggy. Yes there's a small latency penalty. But also most controllers don't suffer from those issues and for the vast majority of use cases on this forum this "All USB is unusable" mindset is wrong.

If you think USB HD/SSD controllers typically burn out in a period of months then you need to provide some proof. That's just bull.

 

[danb35]

If you think USB HD/SSD controllers typically burn out in a period of months then you need to provide some proof.

Nobody's saying they do. What they are saying--because it's true--is that they're notoriously unreliable in maintaining a stable connection to the host. If you've had a good experience, great--but many others here have had contrary experiences. It's not like we own stock in LSI.

 

[alugowski]

Nobody's saying they do. What they are saying--because it's true--is that they're notoriously unreliable in maintaining a stable connection to the host. If you've had a good experience, great--but many others here have had contrary experiences. It's not like we own stock in LSI.

No, they literally said that controllers are burning out:

Problem: if you do anything other than occasional backups to that pool, you'll wind up burning out either the USB to SATA controller or the USB controller after a relatively short amount of time (months, not years) due to the intensity of transaction group IO.

 

[sretalla]

If you think USB HD/SSD controllers typically burn out in a period of months then you need to provide some proof. That's just bull.

I have a small graveyard of external USB enclosures from years back when I was dumb enough to think I knew better and USB was fine because "look, it's working!".

Seems you're in that phase... so I'll just wait for you to join me on the other side. I implore you to have good backups of any data you care about in the meantime. I haven't lost data as the USB enclosure failures were recovered by connecting the disks directly to SATA, but I consider myself lucky.

Anyway, folks own their own hardware and data and the software is open-source, so do what you want, my advice is given here for free in the hope that it helps somebody. Good luck with your theories.

 

[sretalla]

Also... there's this in the official documentation (https://www.truenas.com/docs/core/gettingstarted/corehardwareguide/#storage-media) :

Avoid using USB-connected hard disks for primary storage with TrueNAS. You can use USB Hard Disks for very basic backups in a pinch. While TrueNAS does not automate this process, you can connect a USB HDD, replicate at the command line, and then take it off-site for safekeeping.

 

[heisian]

Sorry to resurrect this thread.

I am coming across this because I started hearing some noise from my trueNAS box. At first I thought it was one of the internal HDD's but turns out it's my external Seagate 10T backup drive.

I replicate to this drive once per day... is this going to experience the burnout mentioned? It has started making some alarming clicking sounds in the past few days, but SMART data (when plugging it into a different system since SMART can't get any data over uas) don't show any issues.

I'm wondering if at this point it's worth breaking the hard drive (and the warranty), out of its OEM enclosure and connecting it directly via SATA...

 

[Arwen]

If the drive has already started making noise, it may be too late.

One of the more serious problems with using external drives, (USB or eSATA), is cooling. ZFS would want to perform a scrub on it's pool data, which is a ton of I/O and head movement. That can and does create a lot of heat. Which many external enclosures lack proper cooling. I searched long and hard to find some with active / fan cooling, just for this exact ZFS scrub reason.

Of course it is possible that you never setup ZFS scrubbing for that external backup disk.


On the other hand, ZFS replication can also cause a ton of I/O & head movement. Though, perhaps less that a ZFS scrub, it would still likely cause a bit of heat.


For the thought of removing it from its OEM enclosure, I can't advise you.

 

[alugowski]

Sorry to resurrect this thread.

I am coming across this because I started hearing some noise from my trueNAS box. At first I thought it was one of the internal HDD's but turns out it's my external Seagate 10T backup drive.

I replicate to this drive once per day... is this going to experience the burnout mentioned? It has started making some alarming clicking sounds in the past few days, but SMART data (when plugging it into a different system since SMART can't get any data over uas) don't show any issues.

I'm wondering if at this point it's worth breaking the hard drive (and the warranty), out of its OEM enclosure and connecting it directly via SATA...

Clicking means mechanical failure is imminent. If the drive still works then use the warning to gracefully replace it.

USB is a red herring here, such failures are not uncommon regardless of how the drive is connected.

 

[alugowski]

You can try taking it out of the enclosure, but more as education rather than saving the drive. It'll still click. Even if it briefly doesn't, that drive should not be trusted anymore, the mechanical parts are near failure not the interface.

If the drive is a 2.5" (laptop size) then it's almost guaranteed that it doesn't even have a SATA port on it. If you disassemble it you'll see that the USB port is on the same board as the drive controller. Bummer since the SATA versions of the same drives are a lot more expensive than the USB versions, but you can't just shuck them anymore. If it's 3.5" then it might be be SATA with a USB adapter.

 

[derlinus]

I aways get back into this thread when looking for a solution to connect a big external USB storage to do infrequent DR backups. I really find the processes involved too tricky. Would be great to have an "Auto" action that automatically detects if external drive is connected, identifies if it's external media 1 or 2, mounts it, starts the replication, drops a message once done, and unmounts the drive. Having to export and import is utterly unintuitive. Would be great if there was a more simple way of doing this.

 

[Arwen]

I aways get back into this thread when looking for a solution to connect a big external USB storage to do infrequent DR backups. I really find the processes involved too tricky. Would be great to have an "Auto" action that automatically detects if external drive is connected, identifies if it's external media 1 or 2, mounts it, starts the replication, drops a message once done, and unmounts the drive. Having to export and import is utterly unintuitive. Would be great if there was a more simple way of doing this.

Yes, while that would be nice, iXsystems does not have any reason to develop such a function in their Enterprise side. And what you describe will take more than trivial configuration. Like some people might need 2 external drives in a ZFS Stripe for their backups. While others can do it with 1 external drive. Then wanting some data on one backup set, but other data on a different backup set.

Those complications are probably the reason why no one has created such a tool for the home / small business users of TrueNAS. I know I would not create such a tool, as what I have is already quite reasonable for me;

How to: Backup to local disks

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