I have NAT 1:1 configured on MX100 for an internal server using the secondary link, Inbound traffic work fine but when I make a traceroute from the internal server to the public network the server uses the primary link.
Note that traceroute won't produce accurate results in this case. Most likely, the actual traffic from inside of your network to the public IP will never leave the MX or use either WAN port. It will get redirected internally.
Note that traceroute won't produce accurate results in this case. Most likely, the actual traffic from inside of your network to the public IP will never leave the MX or use either WAN port. It will get redirected internally.