Error: The file size exceeds the limit allowed and cannot be saved" Error

[rob_4X4]

Case #07602337

I am backing up from a Windows 11 PC to a QNAP TS-431 NAS using NTFS for the connection.
The NAS Storage volume has a capacity of 21.2 TB and currently has 13.3 TB Free Space.
There are no errors or warnings in the NAS Logs.
Have you any suggestions as to what caused the errors below and how to fix them ?
I am a new user of Veeam and this is my fist test backup so I have not yet managed to perform a successful backup with it.

"10/02/2025 8:03:12 AM :: Initializing
10/02/2025 8:03:15 AM :: Preparing for backup
10/02/2025 8:03:18 AM :: Required backup infrastructure resources have been assigned
10/02/2025 8:04:00 AM :: Creating VSS snapshot
10/02/2025 8:09:30 AM :: Getting list of local users
10/02/2025 8:09:37 AM :: New Volume (C:) (3.6 TB) 2.2 TB read at 46 MB/s
10/02/2025 9:54:31 PM :: Recovery partition (disk 2) (802.0 MB) 718.6 MB read at 69 MB/s
10/02/2025 9:55:29 PM :: EFI system partition (disk 0) (100.0 MB) 100.0 MB read at 9 MB/s
10/02/2025 9:55:39 PM :: New Volume (E:) (14.6 TB) 7.3 TB read at 44 MB/s
12/02/2025 10:16:47 PM :: New Volume (D:) (7.3 TB) 772.1 GB read at 48 MB/s
13/02/2025 2:54:07 AM :: Finalizing
13/02/2025 2:54:08 AM :: Error: The file size exceeds the limit allowed and cannot be saved. Failed to write data to the file [/rob/VeeamAgentUser03560274-043c-0571-4306-5a0700080009/Agent_Backup_Policy_1_-_Office-Desktop/Agent Back2025-02-10T080316.vbk] [size = 1048576] [offset = 8796092698624]. NFS error: File exceeds server max (code: 27). NFS4.1 error. Failed to download disk '9f8b9238-a349-4c3b-8e82-9cf8112b708c'. Reconnectable protocol device was closed. Failed to upload disk. Skipped arguments: [EmulatedDiskSpec>]; Agent failed to process method {DataTransfer.SyncDisk}
13/02/2025 2:54:12 AM :: Processing finished with errors at 13/02/2025 2:54:12 AM
"

Any suggestions on how I can resolve the problem ?

Thanks in Advance

[david.domask]

Hi rob_4x4, welcome to the forums.

Looks like it's the backing filesystem because there's an NFS error being returned:

NFS error: File exceeds server max (code: 27). NFS4.1 error

This seems to map to NFSERR_FBIG which points to the backing filesystem for your NFS repository. Check the backing filesystem behind the NFS share, likely it's ext3 or ext4, but looks like this is being returned by the NAS device when Veeam Agent tries to write data.

[rob_4X4]

Thanks for the advise and suggestion. I will run a disk check on the vol and see how that goes. For others hitting the issue, for a Qnap it is StorageManager->Storage->Storage Space-> Volume then under actions select check file system

[Regnor]

How much data in total are you trying to backup? And how big has the VBK become? As David says it's rather a limitation of the filesystem of the QNAP itself.

[rob_4X4]

Does veeam create one large monolithic file for the backup or is it split across multiple file ?
(PC being backed up does have 3 drives/filesystems on it )

[Regnor]

A single file is created per restorepoint. Fullbackups are stored in .VBK and incremental backups are stored in .VIB files.
Looking at your Volume sizes, I would guess that VBK is getting too big; maybe 16 TB?

[rob_4X4]

The PC does have a log of storage but overall it is less that 16 TB. Also I have high compression enabled to further reduce the storage requirements.

However I do think that the backup in one monolithic file for a device with multiple disks/volumes/filesystems is a significant shortcoming in the architecture Veeam software . Other backup tools do have the ability to store backups over multiple files. Even simple compression/archiving tools like 7zip offer that functionality.

To Veeam staff reading this an enhancement request would be to allow backups to be stored across multiple files rather than one monolithic

I note there are other forum posts discussion this issue and similarly suggesting that being able to split backups across multiple files would be useful

[Gostev]

Please note that we don't recommend using consumer-grade NAS as backup targets in principle, as our support statistics clearly shows they are too prone to data loss. Therefore we're also not planning for introducing any capabilities to accommodate peculiarities of this type of storage, as this will only drive more people to use such targets, which is not something we want to happen. Thanks

[Zweistein]

Hello Rob_4x4,

i think you don`t use NTFS on your NAS, becouse you are reciveng a NFS-Error.
Can you discripe the connection bitwean Windows 11 PC, Backup Server and NAS with more details?