WiFi/LAN Conflict

I wasn't sure where to put this question, but this seemed like the best place.

I've recently started running an HP Elitedesk 800 G2 Mini (65W i5-6500) with a Mesa 7i96e on my CNC router. The HP came with a LAN nic but no WiFi. I found a USB WiFi adapter that uses the Realtek RTL8812BU chipset and was able to install fairly easily. I'm currently running LinuxCNC 2.9.2 Debian 12 Bookworm PREEMPT-RT ISO. The WiFi works great on the HP.....as long as I'm not using the LAN to 10.10.10.10, my Mesa card. When the Mesa card is active and Linuxcnc is running, I cannot use WiFi. As soon as I shut the Mesa card down and stop using the LAN, the WiFi returns and is fully operational. This situation is not a deal breaker, but it would be nice to be able to access my home network and the internet while Linuxcnc is running.

Does anyone have any ideas on how to resolve this? 

Thanks,Dean
 

maybe the default route is switched to the ethernet !?!?
check this command with and without mesa configured:

$ ip r s

default via 192.168.80.1 dev enp2s0 proto static metric 100

Make sure you are running network manager and not wicd

wicd is brain dead and cannot manage 2 links at once properly
 

No idea if this will solve your issue however if you plan on prioritizing the wifi over nic, then the metric needs to be set for both option. And so you might want to set that first. 

### The lowest the metric n is, the highest priority it will be given.
### To find both "your_wifi_conn_name" and "your_wired_conn_name", use:

maybe the default route is switched to the ethernet !?!?
check this command with and without mesa configured:

$ ip r s

default via 192.168.80.1 dev enp2s0 proto static metric 100

I'm not a Linux guy so be patient with me.  I ran this in terminal with and without Linuxcnc running and got the following:

dean@CNC-Computer:~$ ip r s
default via 192.168.0.1 dev wlx347de44fe0f7 proto dhcp src 192.168.0.68 metric 600 
192.168.0.0/22 dev wlx347de44fe0f7 proto kernel scope link src 192.168.0.68 metric 600

and then:
dean@CNC-Computer:~$ ip r s
default via 10.10.10.1 dev eno1 proto static metric 100 
default via 192.168.0.1 dev wlx347de44fe0f7 proto dhcp src 192.168.0.68 metric 600 
10.0.0.0/8 dev eno1 proto kernel scope link src 10.10.10.11 metric 100 
192.168.0.0/22 dev wlx347de44fe0f7 proto kernel scope link src 192.168.0.68 metric 600 

Thanks. Went back and verified I'm definitely running network manager.

The problem is that the 10.10.10.1 address is a default route
That's an error in setting up the 10.10.10.1 interface

Mecanix wrote:

No idea if this will solve your issue however if you plan on prioritizing the wifi over nic, then the metric needs to be set for both option. And so you might want to set that first. 

### The lowest the metric n is, the highest priority it will be given.

$ sudo nmcli connection down "your_wifi_conn_name"
$ sudo nmcli connection modify "your_wifi_conn_name" ipv4.route-metric 100
$ sudo nmcli connection up "your_wifi_conn_name"

$ sudo nmcli connection down "your_wired_conn_name"
$ sudo nmcli connection modify "your_wired_conn_name" ipv4.route-metric 200
$ sudo nmcli connection up "your_wired_conn_name"


### To find both "your_wifi_conn_name" and "your_wired_conn_name", use:
[code]$ nmcli connection show

[/code]
 

Thanks mecanix!  That seems to have made the difference.  I can now run Linuxcnc and get to my network and the internet all at the same time.

You guy are the best!

Dean
 

PCW wrote:

The problem is that the 10.10.10.1 address is a default route
That's an error in setting up the 10.10.10.1 interface

I set up the nic based on tommylight's sticky on "Mesa ethernet setup for 7i92, 7i96, 7i76E and other ethernet Mesa boards".  The nic is set with an address of 10.10.10.11 and the gateway is set to 10.10.10.1.
Everything seems to be working great now.

That might be the error, no gateway should be setup
on the real time link. In other words I think setting up
a gateway address gives you this:

default via 10.10.10.1 dev eno1 proto static metric 100 

Which is the issue (general internet traffic is routed out eno1)