iSCSI volume on windows 11 getting corrupted

TrueNAS General
1

Hi,

I connect my Windows 11 machine to my NAS using an iSCSI connection. This setup works well most of the time, especially when using a large MTU size (9000). However, every once in a while, my Windows machine displays an error indicating that the volume is corrupted. I find myself needing to run the Chkdsk command every few weeks to restore read/write access.

I searched online for solutions but only found articles related to older versions of Windows, such as 2012 and 8.

Do you have any suggestions?

Itamar

2

By any chance are there more than one client that is configured to access this iSCSI target? Also hope the filesystem in use is NTFS (just clarifying)

3

Yes, but what I did was to ensure the permission model was to allow everyone full access to the volume.

4

Or at least that I thought I did… I refreshed these permission now. Was the problem?

5

Mounting an iSCSI volume on multiple clients at the same time is akin to an undefined situation and will corrupt data in short order.

Since it’s iSCSI each client assumes it’s the only one working with the volume and whenever anything needs to change, metadata for example, it assumes it is the only one modifying it. If this isn’t the case, and another client is changing things affecting the same metadata, chaos ensues.

There are ways to do multi-user iSCSI but that typically takes specialist software working as a gatekeeper/wrapper, actively preventing above mentioned corruption. This goes far beyond the iSCSI implementation included in TrueNAS and most other similar software.

Edit: I recommend rethinking your approach. Consider if SMB may be a better access method.

4 Likes
6

Thank you very much, I will switch to SMB

1 Like
7

I have the same or related issue. During iSCSI test I performed today between Windows 11 PRO and TrueNas Scale using mtu of 9000 as well, Windows did crash all ready four times.

Also during transmission of data towards the NAS. So there are definitively bugs in windows. !!

Bug reports are send to Microsoft automatically. I hope they fix it on short term!!

(iSCSI disk on ElectricEel-24.10.2.2, gpt formatted with NTFS 16kb clustersize, I think I saw the same problem with 4K cluster size)

8

How so?
Are you also connecting to the same iSCSI share from multiple clients at the same time?
If so, there’s nothing to fix regarding iSCSI - your usage is invalid.

Swap to a different protocol that supports multiple concurrent clients.

9

I’m basically going to concur with neofusion’s comments. Anecdotes follow.

I’ve had my Windows 11 main system connecting to iSCSI targets for all my storage needs for close to a year now. Not a single issue. Now granted, that was/is a TN Core installation. I’m working on moving everything over to a TN CE/Scale installation and so far no issues.

As correctly pointed out, iSCSI is not by its nature “compatible” with multiple initiators unless something else more intelligent in can work around those limitations.

1 Like
10

I noticed that the crashes I had where related to file transfers in general also local file transfers. I still have to find the cause.

Whatever my reaction somewhat higher was not correct. Sorry