[Samba] SMB Multichannel not working?

[Carter Sheehan]

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.

Is there any more info I can provide to you?

Carter Sheehan
Cloud Engineer
o: +1 (781) 224-7753<tel:+1%20(781)%20224-7753>
e: csheehan at vestmark.com<mailto:csheehan at vestmark.com>

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________________________________
From: Jeremy Allison <jra at samba.org>
Sent: Thursday, February 2, 2023 5:04 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 Thu, Feb 02, 2023 at 09:52:09PM +0000, Carter Sheehan wrote:
> Jeremy,
> My apologies, and thanks again for all the help!
> My client is just Windows Server 2019 with nearly default settings for the
> SMB Client (which should use SMBv3 by default hence the dialect 3_1_1). I
> have been able trigger SMB Multichannel when connecting via SMB to
> another windows host so I know my client is capable in its current
> hardware configuration.

I think you need to stop the "old" SMB1 -> SMB3 negprot upgrade
path from this client. I don't understand why it's doing that and
not just starting immediately with SMB3. I think that might have something to do
with the issue. I'm exploring further.

> As for the wireshark packet capture, I'd love to share that with you, do
> you have a preferred place for file sharing?

Nope, any place you can upload/share works for me.