title: Openvpn client can only ping one of two interfaces in the same AWS Linux 2 instance
body: <p>I have an AWS Linux 2 instance, with two interfaces in different subnets, where I installed <strong>Openvpn</strong> using the <strong>172.23.0.0/24</strong> network. <strong>Openvpn</strong> is working and I can connect to it. However, from the remote client I can only ping the interface connected to the Internet and the <strong>Openvpn</strong> tunnel interface which has the <strong>172.23.0.1</strong> address. I can not ping the other interface with the <strong>10.0.0.8</strong> address. From the instance, I can ping all addresses. If I run tcpdump, I can see the packets arriving from the remote client, but the interface does not respond.</p>
  <p>I have stoped source and destination check and I have also activated ip forwarding with <code>sysctl -w net.ipv4.ip_forward=1</code> and even tried <code>sysctl -w net.ipv4.conf.all.proxy_arp=1</code> and <code>sysctl -w net.ipv4.conf.all.proxy_arp_pvlan=1</code>. This is a brand new instance where the only thing installed is Openvpn. No firewall.</p>
  <p>Can not figure this out and would appreciate some help.</p>