Windows 8.1 - multichannel SMB 3.0 - no switch?

[boed]

Hello,

If I have 2 PCs, can I use SMB 3.0 multichannel without a switch?

My PCs are both win 8.1

They have 3 network connections - 2 onboard realtek and 1 addon card - Intel CT.

I'd like to have 2 cables going between the 2 PCs just for the SMB Multichannel and use a 3rd port for internet with a gateway. I'm not familiar with MS's built in solution or if it can be done without a switch set up for LAG.

 

[azazel1024]

As I mentioned in my PMs, yes, you can do that, but since they'll be connected to the same gateway/router, you must enter routing rules on both machines so that they will only talk to each other using their direct connected NICs, otherwise they can/might/will try to talk to each other over the 3rd network connection, which might not end up playing well with SMB Multichannel/networking in general.

My suggestion, get a cheap 5 port or 8 port gigabit dump switch for $15-20 and hook them up that way. SMB Multichannel does not need link aggregation to work (in fact enabling it "breaks" SMB Multichannel as a link aggregation group is treated as a single network interface).

 

[boed]

Thanks - I haven't gotten tot he PMs yet. I'm doing this without a switch so they won't go through the same router. I'm using just enthernet cables between each nic - no switch in the middle.

So for example on nic one I have an IP 192.168.101.22, 255.255.255.0 GW 0.0.0.0 next nic 192.168.101.23, 255.255.255.0 GW 0.0.0.0 etc for the 4 nics.

The third nic isn't plugged in on the second PC and the the 3rd nic on the first PC has a gateway but it is on a 10.10.100 network.

This is how it is configured now but no increase in speed so I'm guessing I have to do something to make the SMB 3.0 multichannel the nics.

 

[boed]

Only problem is even though under my network settings advanced - both show rss as enabled, powershell doesn't see them as rss capable. They have the latest drivers.

PS C:\Windows\system32> Get-SmbClientNetworkInterface
Interface Index RSS Capable RDMA Capable Speed IpAddresses Friendly Name
--------------- ----------- ------------ ----- ----------- -------------
19 False False 1 Gbps {192.168.101.105} Ethernet 2
18 False False 1 Gbps {192.168.101.100} Intel LAN
17 False False 1 Gbps {10.100.100.100} Ethernet


Yet Netsh looks good

C:\Windows\system32>netsh int tcp show global
Querying active state...
TCP Global Parameters
----------------------------------------------
Receive-Side Scaling State : enabled
Chimney Offload State : disabled
NetDMA State : disabled
Direct Cache Access (DCA) : disabled
Receive Window Auto-Tuning Level : normal
Add-On Congestion Control Provider : none
ECN Capability : disabled
RFC 1323 Timestamps : enabled
Initial RTO : 3000
Receive Segment Coalescing State : disabled
Non Sack Rtt Resiliency : disabled
Max SYN Retransmissions : 2
Not sure what the solution is.

 

[boed]

Another place in Win8 it appears I should have RSS showing good under smbclient interface but doesn't is if I run
Get-NetAdapterAdvancedProperty
Intel LAN Receive Side Scaling Enabled *RSS {1}

 

[avos]

As I mentioned in my PMs, yes, you can do that, but since they'll be connected to the same gateway/router, you must enter routing rules on both machines so that they will only talk to each other using their direct connected NICs, otherwise they can/might/will try to talk to each other over the 3rd network connection, which might not end up playing well with SMB Multichannel/networking in general.

My suggestion, get a cheap 5 port or 8 port gigabit dump switch for $15-20 and hook them up that way. SMB Multichannel does not need link aggregation to work (in fact enabling it "breaks" SMB Multichannel as a link aggregation group is treated as a single network interface).

Multichannel actually still works with NIC Teaming enabled.

http://blogs.technet.com/b/josebda/archive/2012/05/13/the-basics-of-smb-multichannel-a-feature-of-windows-server-2012-and-smb-3-0.aspx

It is the SMB-Direct which uses RDMA that breaks if you turn on NIC teaming.

 

[azazel1024]

Multichannel actually still works with NIC Teaming enabled.

http://blogs.technet.com/b/josebda/...ature-of-windows-server-2012-and-smb-3-0.aspx

It is the SMB-Direct which uses RDMA that breaks if you turn on NIC teaming.

That is funny, because when I enable teaming with my Intel Gigabit CT adapters, SMB multichannel stops working with that team. I supposed you could create two seperate teams and then the teams would work together through SMB Multichannel, but other than that, it appears to break it.

On the mixed NICs with SMB Multichannel not working, I haven't tried anything other than same manufacturer, with the sole exception of trying my USB3.0 GbE adapter with the onboard NIC on my laptop, and that did not work.

I have not tried the Realtek NICs on my server or desktop along with the Intel Gigabit CT adapters in both machines to see if they'll work (yet).

 

[boed]

I ended up fresh installing Windows and RSS is now working.

 

[azazel1024]

I ended up fresh installing Windows and RSS is now working.

Well that is certainly a good thing. Odd though, but then again plenty can be odd with Windows (especially networking stuff!!!)