File is too large for destination file system

TrueNAS General
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I just Rebuilt my Nas of eight years on TrueNAS-SCALE-Fangtoot
I have 17 12Tb Drives two 8 drive wide raid Z2 with a hot spare and TrueNAS Mini Write Cache ~130Tb total.
Every time I try to copy my files over it creates the folders and touch files of 0 bytes then Errors out first it says “The destination has 51152 files with the same names” then “file is too large for destination file system” it doesn’t matter the size of the file (most are 200Meg to 47G in size). I did not have this issue in TrueNas Core. I am coping the files over SMB from a Windows Box and a few Qnap NAS’es. the user doing the copy has full permissions. I am coping them via mounted SMB shares.

Hardware Spec’s

Ryzen 9 9900x
128g
LSI 9305-24i
ASrock Rack Motherboard.
Unboard 10g card

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First of all, Welcome to the TrueNAS Forums. Hopefully we will be able to lend you assistance.

Second, please refer to the link “Joes Rules”, a quick and dirty set of information to help you help us to help you (that was a mouthful). It lists things like the data we find helpful in order to provide you assistance. Part of that is also forming a very clear question and what is happening on your end.

This statement is very vague. You do not specify copy files from/to. Very important. Part of Joes Rules is to do your best to not let us assume we know exactly what is going on. We have a good understanding of things however we do not know “exactly” what is going on in your system and honestly, assumptions can really drag a problem out or even cause bigger problems. Your hardware could be affecting something. In this specific case, I doubt it is a hardware issue but thanks for providing the specs, it may help.

I’m sure once you have provided better details, someone will offer to help you out. But remember, no matter how smart some of us are, it is not the same as being present on the machine having problems, so details matter.

Have you tried a search for the error message? Removing the numerical count of course. I found a few hits, it might be worth investigating while you wait on some help.

Again, welcome to the forums and I hope your problem can be addressed swiftly and without any data loss.

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Sorry I thought the line stating “I am copying them over SMB from A Windows Box from a few Qnap Nas’s” would have provided enough details.

I did try searching on here and Google those solutions didn’t help but what has helped is if I copy the files to my Workstation first, sure it is a huge PITA to copy 2.5M files 4tb at a time (amount of free space on my Workstation) but that is working which leads me to think this is some Extended ACL

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I’m sorry, it was late and apparently I cannot read when I’m tired. But I still have a question about that. Exactly how are you doing the copy? Using Windows 11 and File Explorer, then dragging the files over? I would suspect so but I need to ask.

How many files are you trying to copy in a single move? If it is 51152 files in a single move, do you think File Explorer is overwhelmed?

Permissions, I really hate those things and I am far from the ACL expert.
For your SMB settings for one shared space, do you have the ACLs set for everyone@, FULL, and ALLOWED? I suspect you do but need to ask.

Have you tried to use something like SyncToys 2.1 to copy files? I’m not certain it would make a difference but possibly worth a shot.

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Another tool you can use to copy via Windows is SyncBack free.

However, you would probably be better off using rsync and copying direct from one server to another.

And depending on the maximum speeds of network cards in each box, and the speed of your actual network, you might even be better off doing the rsync via a direct connection between the two boxes.

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I thought about that but not using rsync myself, I didn’t want to say it. But good recommendation.

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I have had a similar problem copying files between network sources via SMB on my Mac, but have had no issues copying to or from network locations.

Something is different about a network to network copy than a local to network or network to local copy.

I suspect it is not an ACL issue, but wait, when you created the dataset on the TrueNAS, which Dataset Preset did you use?

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Back to where I was, I do not suspect an ACL issue but a limitation of the tool you are using on the client side. Note that Explorer (Windows) and Finder (macOS) do more than just copy a file when they are instructed to copy a file. You may be able to use a command line tool (via Powershell) such as xcopy to copy directly between network shares (probably easier to mount them to drive letters in this case). But, I am not a Windows expect, so take this last suggestion for what it is worth.

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I have all of my NAS SMB shares mapped as drive letters on my Windows 11 system. I prefer this method due to my familiarity with the Windows interface for navigating and managing files.

Recently, I attempted to transfer several project folders to a new TrueNAS archive system. One of these folders, approximately 21.5TB in size and containing around 50,000 files, failed to copy and returned the errors I previously mentioned. I also tested a smaller transfer consisting of just 15 files totaling under 1GB, and it too failed with the same errors.

I do not believe the issue is related to File Explorer being overwhelmed. For comparison, when migrating data to the new NAS, I previously transferred over 60TB across multiple project folders—comprising more than 2 million files—using File Explorer without issue, allowing the process to run over a weekend.

To rule out drive letter mappings as the cause, I attempted to copy files directly to the SMB share using the UNC path (e.g., \\<NAS_IP>\Backup\project1974\). However, this method resulted in the same failure and identical errors.

This is the same workflow I’ve successfully used with various NAS systems when backing up to TrueNAS. These issues only began occurring after updating to the latest version of TrueNAS.

One potential variable worth noting: I am able to copy files without issue from at least one other NAS (a QNAP device). The largest data set, however, resides on a TerraMaster NAS with six nearly full 24TB drives. Interestingly, if I copy the data to my workstation first using the same method, and then transfer it to the TrueNAS system, the operation completes successfully.

When I created the Dataset, I selected SMB if I remember correctly.

I plan to conduct additional testing when I return to the office.

As a side note, I used the same file transfer method to move data off the old TrueNAS Core system without encountering any problems.

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Like I said, I have seen similar behavior on macOS. I have also seen USB drive to local fast and USB drive to NAS slow.

Good, that means the dataset should be setup for SMB ACLs instead of basic Unix permissions.

Have you attempted a command line copy?

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How long are the paths involved here (full folder path + longest file names)?
Count the characters in the source path, from the root/drive letter. If your path has letters that deviate from a-z and/or numbers, please also specifically state that.
Do the same for the destination path, from the perspective of Windows.

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Under 128 Characters most under 64 names are \projects\XXXX\ with folders under the XXXX of Week01 to Week99

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Question for the group and just for testing purposes:
Can @Belezeebub create a new dataset using Generic, UNIX permissions 777 or similar, then toss it on the network as an SMB share. If he is able to transfer files then we know it is a permissions issue.

I’m thinking of trying to isolate/identify the problem.

Does this make sense?

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I would try to copy a single file to see if it is an issue of permissions or of quantity.

If it fails on a single file, then trying different permissions seems to be a sound next step.

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Fails on a single file also, but again if I copy the file s to my workstation first it works with no other changes