I need help configuring eth0 and wlan0. The “Warning” message below appears each time I open “Network Settings” in YaST. Sure enough the systems hangs periodically during heavy network usage.
What I have tried:
I set the Ethernet card to “Hot Plug” and changed it to a static IP thinking that would remove the conflict. no luck.
I checked the eth0 and wlan0 configuration files to insure the network card was configured for a static IP and the wireless adapter was configured as DHCP. See Below.
Then I rebooted the system: no luck., “Network Settings” continues to display the “Warning”.
My question: Why is ifcfg-eth0 still indicating it is using DHCP in the warning message? What Do I need to do to resolve the conflict?
This is a new install of OpenSUSE Leap 42.2. I install it using a Network Install and the Network card. Once it was installed I added the Wireless (WUSB600N Version1) adapter.
Warning
More than one interface asks to control the hostname via DHCP.
If you keep the current settings, the behavior is non-deterministic.
Note what the warning says exactly.
It’s not saying that you have an IP address conflict, it’s saying that the same Hostname is assigned to both network interfaces.
This is because when your machine is online, Hostnames are supposed to be unique and right now you are configuring multiple active interfaces using the same name… So when other machines want to access your machine by Hostname, they’ll find multiple active IP addresses and won’t know which to use.
Solution:
Only use one network interface on any network at a time.
You can disable your wireless if you have a hardware (or software in the OS) switch if you wish to use your wired connection.
You can physically unplug your wired connection if you’re using your wireless.
You can use rfkill as a software switch to disable or enable any networking interfaces.
Note that if your network devices connect to <different> networks you won’t have that problem and could theoretically have more than one network connection, but in that case only one network connection should be assigned a Default Gateway.
Thanks tsu2, you gave me what I needed to figure it out. All I needed to do was go to “Network Settings”->“Hostnames/DNS” tab and change “Set Hostname via DHCP” to “yes:any”. This cleared up the conflict.
Go to the Network Settings › Hostname/DNS tab in the System module in YaST.
Enter the Hostname and, if needed, the Domain Name. The domain is especially important if the machine is a mail server. Note that the host name is global and applies to all set network interfaces.
If you are using DHCP to get an IP address, the host name of your computer will be automatically set by the DHCP. You should disable this behavior if you connect to different networks, because they may assign different host names and changing the host name at runtime may confuse the graphical desktop. To disable using DHCP to get an IP address deactivate Change Hostname via DHCP.
Assign Hostname to Loopback IP associates your host name with 127.0.0.2 (loopback) IP address in /etc/hosts. This is a useful option if you want to have the host name resolvable at all times, even without active network.