Resolved Network Service Order - Ethernet ahead of WiFi - but WiFi gets chosen even if Ethernet is available

[Gwendolini]

Hello.

I have a 2021 16" MBP and an OWC Thunderbolt 3 Dock for the Ethernet connection.
When my MBP is in clamshell mode and has the TB Dock connected, Ethernet is available and the Service Order is set to have Ethernet on top, but nonetheless, WiFi gets chosen for data transfers, which is a difference of 80+ MB/s (walls of steel).
Shutting off WiFi helps almost instantly, Ethernet gets chosen almost immediately.

I am also using the latest 12.3 macOS version.

Does anyone have any pointers for this rather stupid problem?

SOLUTION/WORKAROUND - see Chancha's post below.

 

[Chancha]

Is your file transfer over SMB network shares? One scenario is if they were mounted when your MBP was not docked thus on WiFi, the connection "remembers" the NIC to route with, that even when you do dock the MBP where the wired connection is supposed to overtake, the actual file transfer would not switch over since there is no action to trigger the switch. We face this issue all the time in our studio, have to manually switch off and on WiFi, for the brief seconds the only connection will be the ethernet then it is safe to turn WiFi back on.

 

[Gwendolini]

Is your file transfer over SMB network shares? One scenario is if they were mounted when your MBP was not docked thus on WiFi, the connection "remembers" the NIC to route with, that even when you do dock the MBP where the wired connection is supposed to overtake, the actual file transfer would not switch over since there is no action to trigger the switch. We face this issue all the time in our studio, have to manually switch off and on WiFi, for the brief seconds the only connection will be the ethernet then it is safe to turn WiFi back on.

According to GET INFO of the mounted shares AFP is used. But I guess the same principle applies there?
I will do a check.

Yes, switching on the WiFi again while a transfer at 110 MB/s is happening does not switch the adapter.

And a new transfer, initiated after WiFi was turned on again, also did use Ethernet.

That is a solution I can work with - not beautiful but useful. Thanks for the tip.

 

[Chancha]

AFP and SMB probably are handled the same in recent macOS versions.

For our case our wired ethernet is 10G so this issue is immediately obvious to us. Sometimes we would start a 100GB footage / audio file offload to the team server and leave for a coffee, only to come back with the progress bar hardly moved whereas with the 10G it would have been done 5 times over.

I am not happy with how Apple (not) handling this but at least there is a solution.