I have a faew servers all hosted at a local datacenter. Each server has 3 NIC's installed. Each server has a NIC for the backup network at the datacenter, a NIC for accessing the public internet and the third NIC is for a private network. On the Microsoft SQL server, we do not have the NIC with public internet access enabled, so it access the other servers via the private network, 10.0.0.X
When I ping from server1 to the SQL server, it responds with a IPv6 address. Ultimately, I am trying to resolve this issues so they respond via IPv4. On the SQL server, it seems if all traffic is being routed out the backup network NIC and not the private network NIC as it should be. If I disable the backup network NIC and only have the private NIC enabled, I can no longer RDP between servers and they don't respond to any ping request. I've even added the private addresses to the host file and no luck. I've also disabled IPv6 in the private NIC on all servers.
Is there a way to say which NIC the server should use first?