[Samba] SMB Multichannel not working?

Carter Sheehan csheehan at vestmark.com
Thu Feb 2 21:52:09 UTC 2023


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.

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

Carter Sheehan
Cloud Engineer
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Subject: Re: [Samba] SMB Multichannel not working?

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On Thu, Feb 02, 2023 at 08:48:01PM +0000, Carter Sheehan via samba wrote:
>Thanks for the clue, but I am confused by the response and evidence. In the screenshots, as you can see there are 2 protocol negotiation requests from the client (1 of SMB protocol, the other of SMBv2). In the first request (SMB protocol) there simply is no part of the packet that mentions capabilities. Is that expected from an SMB protocol packet, should the client have specified it's capabilities? It's only when the protocol switches to SMBv2 that the capabilities are listed (and that's where the contradictory responses from the server come from).
>It's worth noting that the Get-SmbConnection command in PowerShell on my client side shows that the dialect chosen is SMB 3_1_1, and when I run the command smbstatus on my server I can see the client connected with SMB3_1_1.

You have to realize I can't read the things you posted,
and you're not giving access to the wireshark traces,
so I'm just going via your text descriptions.

So it looks like your client is doing the SMB1 -> SMB2 bootstrap
in negprot. That usually only done for "old" connections to
unknown servers.

Try just removing the SMB1 client code from your client.
Why is it even there ?

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