First, I am not an Unraid expert.  I'm  just trying to use a NAS for lots of storage and redundancy, etc.  Please be kind, as if I'm a complete newb, just trying to get things working well.  If you could provide easy-to-understand advice, I would really appreciate it.  All the many configuration options can get rather daunting.

 

I am using Unraid as a NAS for my Windows 11 desktop.  My primary share is mounted as my U: drive.  I use it to store media for my Plex server.

 

I know it would be better to run my Plex server on Unraid itself, but instead I am running it on Windows and using the NAS as its storage.  Unraid is running on a very old PC with a very old video card. (I should buy it a new card.)

 

I set up my Unraid several years ago, and it has been working well, but today I started getting the "There is not enough space" error message even with minuscule files.  For example, I used Windows File Explorer to create a new (empty) Text Document.  This worked.  The file is empty.  Then I used my favorite text editor - vim - to add text to the file.  Just a few characters.  When I tried to save the changes, I got the "not enough space" error message.

 

I will reboot Unraid to see if that helps, but in the mean time...

 

I first saw the error message today when I tried to download a 2 MB file.  So I download onto local disk and tried to copy it to my Unraid share.  Same problem.

 

I have three 12 TB hard disks in my one and only array.  All three have plenty (gigabytes) of free space.  I will provide a screenshot of my Arrays.

 

I also have two 1 TB SSD's in a Pool for cache.

 

My primary share - "data" - seems to have 3.42 TB used and 33.3 TB free.  Disk1 has 2.43 TB used and 9.49 TB free.  Disk2 and Disk3 aren't listed.  I don't understand why.  I'll provide a screenshot of my Shares as well.

 

Other than that, I believe I have done minimal configuration other than to add some plug-ins and dockers.

 

I think I have plenty of free space in my share, and I don't understand the problem.

 

I'm sure that the like many newbs, I assumed that a share would just span the the array it is allocated to, and that the data in the share would be distributed - hopefully evenly - amongst the disks in the array.  Because the share info is not listing Disk2 and Disk3, I think this is not happening,  Right?  If it's not, is there a way to make it so?  I would prefer not to bang on the same disk all time.

 

 

Many thanks for any assistance you might give.

---Mark

 

Attach Diagnostics ZIP to your NEXT post in this thread.

There you go.  Sorry, my first problem to report.

 

I have rebooted Unraid and I still see the problem.  I can't edit the text file and save it.

muttraid-diagnostics-20250411-1008.zip

The space used is as expected - you need to read up here on how the default High-Water allocation method works if you want to understand why.

1 hour ago, itimpi said:

The space used is as expected - you need to read up here on how the default High-Water allocation method works if you want to understand why.

I assume this is a response to this issue. Nothing to do with the out-of-space problem.

3 hours ago, 4WoofGrrrr said:

I assumed that a share would just span the the array it is allocated to, and that the data in the share would be distributed - hopefully evenly - amongst the disks in the array.

 

You have 2 different issues you are asking about. Allocation Method, as mentioned, is the reason your 'data' share hasn't begun to use the other array disks yet. I recommend not worrying about that. Highwater is the default for good reasons. It allows all disks to be used eventually, without constantly switching between disks.

 

Which share is giving you the out-of-space error?

Your cache is very full, and you have no Minimum Free set for cache, so it can't overflow to the array.

 

https://docs.unraid.net/unraid-os/manual/storage-management/#minimum-free-space-for-a-pool

 

Also your docker.img is corrupt and so has been made read-only. You will have to recreate and reinstall from Previous Apps.

 

https://docs.unraid.net/unraid-os/manual/docker-management/#re-create-the-docker-image-file

 

https://docs.unraid.net/unraid-os/manual/docker-management/#re-installing-docker-applications

 

https://docs.unraid.net/unraid-os/manual/docker-management/#docker-custom-networks

Makes me wonder if cache hasn't also been made read-only, since you have filled it, so that might be the reason for out-of-space. Didn't really see that in syslog though.

 

You should install Fix Common Problems and let it do a scan. It will check that cache can be written. Kind of surprised you don't already have FCP if you have been using Unraid for a while.

I also recommend removing mover tuning plugin, at least until your problems are resolved. The one you have installed is deprecated anyway.

 

And your appdata backup plugin is deprecated. You should uninstall and then install the new one.

Thank you for your help.  I'm not sure I entirely understand what all of this means, but I did read the pages you referred me to and (tried to?) followed the recommendations.

 

Firstly, I apologize for bringing up two different topics in the same request.  I should have known better.

 

In answer to your question: the share that is giving me the out-of-space error is "data".

 

I have recreated docker.img and have (automatically) re-installed the previous apps.

 

After that, I shut the Array down, changed the Minimum Free Space to 1GB, and restarted the array.  I can save files now.

 

The help for Minimum Free Space confuses me.  It says:

 

Quote

This defines a "floor" for the amount of free space remaining in the volume. If the free space becomes less than this value, then new files written via user shares will fail with "not enough space" error.

 

So now, because I have changed the setting to 1GB (it was previously "0", which I thought would mean there was NO minimum) if free space gets BELOW 1GB, new files will fail???  Does that mean that I can save a file now only because I restarted the array and the cache got emptied in the process???  And if free space gets below 1GB in the future, saves will start to fail again?

 

I have also read more about this on the Storage Management page you referred me to.  It makes me believe that if the space drops below 1GB, the cache will be bypassed and data will be written directly to the array.

 

I am sure I am fundamentally misunderstanding how the cache works.  I had thought it would be simply be used to cache the most-recent and/or most-frequently-used data and anything else would be automatically moved to the array.

 

Could you please refer me to more basic information - an overview, perhaps - of how this all works?

 

Thanks again.

 

New Diagnostics might clarify some of what you did without additional questions.

2 hours ago, 4WoofGrrrr said:

The help for Minimum Free Space confuses me.  It says:

That quote is at the very least incomplete, and I can't find that quote in the help I linked. Where are you looking?

OK, I see you got that from the help in the webUI. 

 

If cache has less than Minimum, and the user share being written has no Secondary storage, then it is true that it will fail. But if the user share has secondary storage, it will go to the secondary storage. Typically this is the array. This is known as overflow.

 

https://docs.unraid.net/unraid-os/manual/shares/user-shares/#primary-and-secondary-storage-unraid-612

Each user share also has a Minimum Free

https://docs.unraid.net/unraid-os/manual/shares/user-shares/#minimum-free-space

 

For pools (such as cache), if it has less than Minimum, new files are written to Secondary storage if that is set.

You should set Minimum for cache to larger than the largest file you expect to write to cache. (1G is not nearly enough).

 

Some examples. The user share is configured Primary:cache; Secondary:array.

 

1) Minimum Free is set to 20G, cache has 25G free.

You write a 15G file to the user share. Cache (Primary) has more than Minimum, so it will be chosen. After the file is written, cache will only have 10G free. If you write another file to the user share (no matter the size), the array (Secondary) will be chosen.

 

2) Minimum Free is set to 20G, cache has 25G free.

You write a 30G file to the user share. Cache (Primary) has more than Minimum, so it will be chosen. The write will fail when cache runs out of space.

 

Minimum for user shares is similar. You should set Minimum for each share to larger than the largest file you expect to write to the share.

 

If the array is chosen for the write, and a disk has less than Minimum, another disk will be chosen for writing.

In the general case, Unraid can't know how large a file will become when it chooses a pool or disk to write the file to. After it chooses a disk, it will try to write the whole file there, and if there isn't enough space the write will fail.

 

So Minimum must be larger than any file you expect to write to the pool (or share).

6 hours ago, trurl said:

Makes me wonder if cache hasn't also been made read-only, since you have filled it, so that might be the reason for out-of-space. Didn't really see that in syslog though.

 

You should install Fix Common Problems and let it do a scan. It will check that cache can be written. Kind of surprised you don't already have FCP if you have been using Unraid for a while.

I guess I was kinda looking more for a set-it-and-forget-it solution?

 

Anyway, I installed FCP and ran it.   The dialog said it may take a minute.  It' been more than 10.  Am I being impatient?

 

6 hours ago, trurl said:

I also recommend removing mover tuning plugin, at least until your problems are resolved. The one you have installed is deprecated anyway.

 

And your appdata backup plugin is deprecated. You should uninstall and then install the new one.

Done.  Thanks.

39 minutes ago, 4WoofGrrrr said:

Anyway, I installed FCP and ran it.   The dialog said it may take a minute.  It' been more than 10.  Am I being impatient?

I read up on this, and it seems some people have needed to reboot to get FCP working.  So I rebooted and re-scanned.  Worked great this time.  Just a few warnings which I fixed.

 

Thank you so much for helping me with all this.  I learned a little and I fixed a lot.