3

My work network is a little weird. I have a Wireless connection that is primary, but I have a ethernet connection for LAN that also connects to the Internet.

For some reason, the network always connect to the WiFi first, even when I have the connection below Ethernet in the Network System Preference.

Does anyone know how I can fix this? It happened with Big Sur and Monterey.

Current Setting in Network System Preference described in question

2 Answers 2

4

The order in which the various network interfaces connect is not really important. Even though WiFi connects and get an IP address before another interface, does not mean that traffic will flow through that WiFi interface for that reason.

The service order essentially means that if you want to establish an outgoing connection and have two routes of identical specificity towards the destination, then the service order determines which route to take.

Some examples:

You open a connection for "google.com" and the most specific route for that is your default gateway. You have one for the WiFi interface and one for the Ethernet interface. As you have prioritised Ethernet higher in your service order list, the data will travel out the Ethernet port.

You open a connection for "192.168.10.1", a NAS server that is connected directly to your WiFi-router. The most specific route is for 192.168.10.0/24 via your WiFi router. In this case, the data will travel out via WiFi.

Another computer connects to your computer via WiFi for a file transfer. Your computer knows that the other computer is accessible both through WiFi and Ethernet - however the service order does not come into play here - the data is sent back via the same route the connection request came through. That is, the file is transferred via WiFi.

3
  • You are a fount of great information jksoegaard.
    – IconDaemon
    Apr 2, 2022 at 1:06
  • That is all correct. My issue is that it's not actually following that logic. The wireless is what is being used to make the connection. It's easily shown by when Iturn off wireless, the actual transfer speed goes to full 1Gb to sites such as Apple's downloads. Apr 2, 2022 at 13:08
  • It is following that logic. Please give more details about your problem, otherwise it is really hard to help you. I.e. what do you mean by “connection”, what are you transferring and how (protocols, source/destination, etc). Share routing tables if you have changed anything there.
    – jksoegaard
    Apr 2, 2022 at 15:39
1

It turns out that IPv6 affects the network order separately. If IPv6 is turned off, the network priority behaves as expected. IPv6 was only on for my wireless network. Turning IPv6 to a local only link made it "work".

I'd consider this a bug, but may be that it prioritizes IPv6 over everything, and would follow the rules if both networks.

Theory of actual results for my case's network priority

  1. Ethernet IPv6
  2. Wireless IPv6
  3. Ethernet IPv4
  4. Wireless IPv4

If someone has a network they can test this on, please post a reply or an answer.

Credit to Michael Lowry from Network service order not honored from the Apple Discussion site

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .