17.10 wifi gets Internet, but LAN is unreachable

[lpetrov01]

I have a problem with wifi after upgrade to 17.10. I have three computers: A, B, and C that are connected to
a router. A and B are Fedora, C is Ubuntu 17.10. C (Ubuntu) starts up wifi. It gets IP 192.168.10.100,
it sees Internet, I can browse internet. Though, the router tells that host C (Ubunutu) has IP 192.168.1.27 .
Hosts A gets 192.168.1.10. A and B cannot reach C: they cannot establish connection to neither 192.168.10.100,
nor 192.168.1.27. Vice versus: host C (ubuntu) does not see LAN under 192.168.1.x, does not see A,
does not see network printer. At the same time, when I plug Ethernet connected to the router to host C,
it gets IP 192.168.1.28 and then host C sees the LAN and vice versus. Thus, this is not a firewall issue.

The problem is that wifi interface (wlo1 in my case) gets 192.168.10.x subnetwork that is isolated
from the rest of the LAN (192.168.1.x). Wired interface (eno1) does not have this problem.
This is a new behaviour in Ubuntu 17.10. I did not have this problem in earlier Ubunutu. I tried
to tweak /etc/dhcp/dhclient.conf, but this did not help.

How to fix that bug? How to make wifi to be connect to 192.168.1.x network? How to make
host C (ubuntu) that got IP via dhclient visible to the local network and vice versus? Any clues?

[wildmanne39]

Hello, I recommend that you upgrade 17.10 to 18.04 because 17.10 is no longer supported and will receive no updates not even security updates so it is at risk when on the internet.

[lpetrov01]

I solved it myself. It turned out the culprit was a repeater (Waylink AC-1200). It may work in two
modes: bridge and gateway. The last mode is default. It was configured as bridge, but then
someboody reset it to the default, gateway mode. As a gateway, it works in the isolated mode
at subnet 192.168.10.x, i.e. it does not see the rest of LAN and does not provide a route to
connect to 192.168.10.x from the LAN. After resetting it back to bridge mode, the problem
was solved.