When use agent based installer to bringup an openshift cluster on bare matel, if the server's BMC support lan over USB. It will create a virtual interface on the operating system with IP address in the 169.254.0.0/16 range, typically 169.254.0.2, and the iDRAC will be at 169.254.0.1.
For example:

# ip a s
...SNIP...
6: idrac: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UNKNOWN group default qlen 1000
    link/ether ec:2a:72:04:23:87 brd ff:ff:ff:ff:ff:ff
    inet 169.254.1.2/16 brd 169.254.255.255 scope global idrac
       valid_lft forever preferred_lft forever
...SNIP...

Then the assisted installer agent will pick such a interface to check the connectivity. Because the link-local address is a network address that is valid only for communications within the subnetwork, it will not reach the other node's eth0(for example, ip address is 20.12.32.10). Therefore, the connectivity check fails. 

The "LAN over USB" interface is only used to communicatie between node and BMC. So, it should not be pick to do connectivity check.

4.11.0

100%

1. Mount agent.iso or discovery.iso to a server support Lan over usb.
Or
1. Mount agent.iso or discovery.iso to an VM.
2. Create a dummy interface with link-local address.

connectivity check fails