Discovered hosts not registered into Foreman

Problem:
The setup is one Foreman server, which is also the TFTP server, DHCP server, DNS server and DHCP Smart Proxy, and multiple hosts all within the same subnet. I am trying to provision the hosts using the single Foreman server. When using eth0 and eth2 on the Foreman server, the discovered hosts are all registered successfully into Foreman.
However, when using eth1, while the hosts can see the discovery menu, they are not registered into Foreman. The Discovery Status is Failure, with the error 1001: Invalid argument - connect(2), body: N/A.
When doing the switch to eth1, I have changed the following configuration options to complement the change in interface:
foreman-proxy-dhcp-interface
foreman-proxy-dhcp-server
foreman-proxy-dhcp-pxeserver
foreman-proxy-dns-interface
foreman-proxy-dns-server
foreman-proxy-dns-reverse
foreman-proxy-tftp-server
Expected outcome:
Hosts can be successfully discovered and registered into Foreman when the Foreman server is using eth1.
Foreman and Proxy versions:
2.1.4
Foreman and Proxy plugin versions:
foreman_discovery is 16.1.2
Distribution and version:

Other relevant data:

Something is wrong with your network configuration.