I installed OpenSuse Tumbleweed on a computer that previously only ran Kubuntu 18.04. With Kubuntu 18.04, I can still browse the internet and access other computers in my LAN with 20 to 30 MB/s.
With OpenSuse, I can access the internet perfectly fine as long as I don't access computer in my LAN. While I access other computers, however, the internet connection for all devices in my network breaks down completely. I cannot even load example.com on my phone then. Access to other computers only happens at 0.3 MB/s if I connect to the router via an Ethernet cable, and with 0.6 MB/s if I connect to the router via wifi. As long as I don't do that, I can access the internet with 20 MB/s (I have a 160 Mbit/s contract).
Now that I can't access the internet with any device as soon as one device starts misbehaving seems like a problem with my router. But my OpenSuse installation is misbehaving.
I checked that all the graphical network settings are the same on Kubuntu and OpenSuse. At least as far as I can tell (same desktop environment but different versions of the configuration tool, so it doesn't look exactly the same but everything is as equivalent as it seems to get).
> ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: enp24s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state DOWN group default qlen 1000 link/ether 00:d8:61:2e:62:65 brd ff:ff:ff:ff:ff:ff 3: wlo1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000 link/ether 18:56:80:e5:68:98 brd ff:ff:ff:ff:ff:ff inet 192.168.0.130/24 brd 192.168.0.255 scope global dynamic noprefixroute wlo1 valid_lft 2794sec preferred_lft 2794sec inet6 2a02:8071:219d:a600:41c1:49fb:eeb3:cb9/64 scope global temporary dynamic valid_lft 603997sec preferred_lft 85197sec inet6 2a02:8071:219d:a600:ef73:ed77:fb48:cfe2/64 scope global dynamic mngtmpaddr noprefixroute valid_lft 1146360sec preferred_lft 541560sec inet6 fe80::992:178b:39ed:13dd/64 scope link noprefixroute valid_lft forever preferred_lft forever
When I connect the computer via an Ethernet cable to a different computer, I can transfer data at a rate of 10 MB/s. I can use wifi to connect to the router and access the internet at the same time.
How do I get OpenSuse to work normally in the network without a hacky setup as described in the previous paragraph?