How to connect computers directly with ethernet?

Question

I try to connect two linux computers via a crossover cable. I need help at troubleshooting.

I configured ip-address , and on PC1 ifconfig-command shows

enp0s7: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.0.1  netmask 255.255.255.0  broadcast 192.168.0.255

On PC2 it shows

en01: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
        inet 192.168.0.2 netmask 255.255.255.0 broadcast 192.168.0.255

when i run ping 192.168.0.2 on PC or 192.168.0.1 on PC2, i get "Destination Host unreachable".

When i ping the wireless devices, it works.

Edit

Sometimes i try to restart or/and shut down NetworkManager. Then it works. i use ubuntu.

Disable network manager. Or better yet, tell it not to touch those interfaces. — Konrad Gajewski, Feb 24 '20 at 21:46

score 1 · Answer 1 · answered Feb 19 '20 at 09:44

1

I'm guessing your wireless devices are also in 192.168.0.0/24 - if that's the case then that's your problem.

Ideally you should specify a different IP range for the direct connection (eg 172.16.0.1 and 172.16.0.2) or - and I don't recommend this - change the netmask for the directly connected machines to 255.255.255.252 - which will be a more specific route and thus preferred. (It will come back to bite you if you want to set up routing to other systems though.

answered Feb 19 '20 at 09:44

davidgo

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Both methods don't work for me. But thank you for the help. – Karl Feb 19 '20 at 22:23
Can you share your route table on PC1 and PC2? (route -n) – davidgo Feb 19 '20 at 22:41
I turned down my wireless devices with "ifconfig down". Then the routing table was empty. – Karl Feb 20 '20 at 11:10
I don't need these wireless devices, because i just want to have a direct cable connection. – Karl Feb 20 '20 at 11:11

How to connect computers directly with ethernet?

1 Answers1