Problem when both wireless and wired are connected

Archived topics about LMDE 1 and LMDE 2
Locked
Doovde

Problem when both wireless and wired are connected

Post by Doovde »

Hello,

I have a Dell Latitude, I recently installed Linux Mint, according to System Monitor: Release 1 (debian) kernel 3.2.0-amd64
Previously I had Ubuntu installed, but the multiple screen handling plus the amount of system failures push me to try other distributions. I have a bit complex development environment installed which requires two network connections:
1 To a customer network with different server e.g. Jenkins etc... (This connection is only available by wired)
2 To the internet through wireless

When I had the same environment in Ubuntu, I solved it by the following command:
sudo route add -net XX.XX.XX.X/XX gw XX.XX.XX.XX dev eth0;sudo route add -net XXX.XX.XX.XX/XX gw XX.XX.XX.XX dev eth0
Before using the command, I didn't get any issues or network problems while the computer was connected to both wireless and wired. I executed this command to route all the traffic from my applications to the correct server.

When I connect the wireless to Internet in Linux mint, it works, but as soon as I plug the network cable, the connection to the internet disappears, and the DNS are only the one from the wired connection, making impossible to access Internet. I have search online for a while, but I cannot find anyone with a similar problem.

The other issue is the network settings in Linux mint, in Ubuntu there is an option in the Network settings to route the traffic. This option is not available. So I try the command:
sudo route add -net XX.XX.XX.X/XX gw XX.XX.XX.XX dev eth0;sudo route add -net XXX.XX.XX.XX/XX gw XX.XX.XX.XX dev eth0
but I get the following message:
SIOCADDRT: No such device

I got this error before in Ubuntu when the network cable is not connected. Now I get even if the cable is connected and the diod blinks

Although I have some small knowledge about Linux, if nobody knows the solution, I would like some advices which parts I should read about. I search for Linux and networking, but the guides I found are not compatible with the version of Linux I have, many commands the mentions cannot be executed.
Last edited by LockBot on Wed Dec 28, 2022 7:16 am, edited 1 time in total.
Reason: Topic automatically closed 6 months after creation. New replies are no longer allowed.
g33kphr33k

Re: Problem when both wireless and wired are connected

Post by g33kphr33k »

By the sounds of it, you are not setting up your routes correctly.

Connect the cable in first and make sure this works. Once that's done, connect to the Wifi and then do "sudo route" to get your routing table.

What you will find is that Linux can only handle having one default route. If I was you I would set this to the wifi gw so you can push all the usual traffic out that way.

Can you list the current routing table as well as the content of /etc/resolv.conf for us to look at?
Doovde

Re: Problem when both wireless and wired are connected

Post by Doovde »

Hello g33kphr33k

Thanks for the reply, you give some hints until I found the nameserver was wrong. After a lot of searching, I found that I could right-click on the icon for the network connection and click "Edit connections". A menu for "network connection" shows up, on the tab "Wired" select "Wired connection 1" and press edit. The "Editing wired connection 1" will show up and on the tab "IPv4 Settings" at the bottom there is a button "Routes". Click on it and "Editing IP4 routes for Wired connection 1" will show up. In the small window there is a checkbox called "Use this connection only for resources on its network", check it and the press OK.

After these steps both network connections are working.

Thanks for the help!
Locked

Return to “LMDE Archive”