[Samba] SMB Multichannel not working?

[Carter Sheehan]

Jeremy,

That's what is so vexxing about this, the SMB client in Windows Server 2019 has SMBv1 disabled by default. Using the articles you provided, I can confirm that SMBv1 is not enabled for the SMB server/client.


Carter Sheehan
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________________________________
From: Jeremy Allison <jra at samba.org>
Sent: Monday, February 6, 2023 2:17 PM
To: Carter Sheehan <csheehan at vestmark.com>
Cc: samba at lists.samba.org <samba at lists.samba.org>
Subject: Re: [Samba] SMB Multichannel not working?


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On Sun, Feb 05, 2023 at 09:11:41PM +0000, Carter Sheehan wrote:
> Jeremy,
> I am clearing the contents of the packet capture with my security team and
> I'll have it available to you some time tomorrow.
> Regarding protocol negotiation, I have tried using some of the available
> server/client min/max protocol config options for smb.conf hoping it would
> "force" the use of SMB3+ but I still see the same SMB/SMBv2 packets in a
> wireshark capture and both the client and server display the connection as
> using dialect 3_11, so that doesn't seem to have any impact whatsoever for
> me.

This is a clients feature I think, not controllable on the server-side.

When connecting to an unknown server a Windows client tries the SMB1->SMB2+
upgrade.

Just remove SMB1 from this client.

https://learn.microsoft.com/en-us/windows-server/storage/file-server/troubleshoot/detect-enable-and-disable-smbv1-v2-v3?tabs=server<https://learn.microsoft.com/en-us/windows-server/storage/file-server/troubleshoot/detect-enable-and-disable-smbv1-v2-v3?tabs=server>

https://learn.microsoft.com/en-us/windows-server/storage/file-server/troubleshoot/detect-enable-and-disable-smbv1-v2-v3?tabs=server#how-to-remove-smbv1-via-powershell<https://learn.microsoft.com/en-us/windows-server/storage/file-server/troubleshoot/detect-enable-and-disable-smbv1-v2-v3?tabs=server#how-to-remove-smbv1-via-powershell>