Configure multiple NICs

Network profiles are identified and assigned during computer startup and each time a connection changes. The three profiles currently in use in the supported Windows operating systems are:

• Domain profile: Active only when the computer can authenticate with a domain controller on all active interfaces (for example, LAN, wireless, and VPN). The domain profile may be more or less restrictive than the other two profiles depending on network security policies.

• Private profile: Active whenever the network type for all active network connections on the computer are identified as private networks. The private profile typically is used in a more trusted environment and is less restrictive than the public profile to allow for network discovery.

• Public profile: Active in all other circumstances. The public profile typically is more restrictive than the private profile because the computer often is connected to the Internet in an insecure location. Network discovery and remote access are disabled rather than explicitly blocking specific traffic.

All programs allowed to communicate through the firewall are blocked if one or more network interface cards (NICs) are configured as "Public Network." When the IP address of a network card changes, the NIC is automatically updated to "Public Network." If even one NIC in a computer with multiple NICs is configured as "Public Network", the firewall exceptions are disabled.

This is particularly important for computers configured to run as a redundant pair. If the TCP/IP properties for a network card are set to obtain an IP address automatically, there is a possibility that the network address will change when the computer restarts. The computer may suddenly change from having a "Private Network" to having a "Public Network," and potentially block the programs that were previously allowed to communicate through the firewall.

Note: An exception to this would occur if the NICs are configured and set to the Public Profile before Application Server is installed. The Application Server installation would allow the necessary programs to communicate through the firewall in the current (Public) profile.

The following describes the key NIC settings for a redundant pair. You configure these settings for both the primary and backup computers. These settings apply if more than two NICs are installed for redundancy (RMC) or other networking purposes, such as networking PLCs.

Important! When configuring NICs for a redundant pair, speed and duplex settings for the standby NIC must match the settings for the primary NIC.

For detailed instructions on how to configure multiple network interface card binding order settings, see Define the NIC order and Configure IP address and DNS settings.

To configure multiple NICs

1. Under Internet Protocol Version 4 (TCP/IPv4) Properties, select the Use the following IP address option and provide an IP address, subnet mask, and default gateway.

   1. For the primary computer, the default gateway should be the IP address that you configure for the backup computer. For example:

      IP address: 100.100.100.94

      Subnet mask: 255.255.255.0

      Default gateway: 100.100.100.95

   2. For the backup computer the default gateway should be the IP address that you configure for the primary computer. For example:

      IP address: 100.100.100.95

      Subnet mask: 255.255.255.0

      Default gateway: 100.100.100.94

   3. A NIC acting as Redundancy Message Control (RMC) does not require a default gateway. The IP address and Subnet mask can be configured as described for the primary and backup computers. The IP address must be configured for a different network than the primary and backup computers. Windows will identify this NIC and assign it a private profile. For example:

      IP address: 192.168.1.100

      Subnet mask: 255.255.255.0

2. Under Advanced Settings, check that the Register this connection's address in DNS option is not selected.

To set the binding order

Windows uses the InterfaceMetric number to determine priority.

To check the existing priorities of your network cards:

3. Launch the Windows PowerShell as administrator.

4. To view the current priority, enter the following cmdlet:

   Get-NetIPInterface

   

   This displays the Interface List. An InterfaceMetric number is listed for each network interface card/adapter. Note that the lowest number has the highest priority.

5. Identify the NIC cards and define the binding order (priority). Check the InterfaceIndex numbers for each NIC. It could be that your cards already have the correct priorities (higher InterfaceIndex numbers have lower priority).

6. If you need to change the priority of your interface cards, use the following cmdlet to change the InterfaceIndex for one or more network cards. For example:

   Set-NetIPInterface -InterfaceIndex 2 -InterfaceMetric 100 (lower priority)

   Set-NetIPInterface -InterfaceIndex 5 -InterfaceMetric 10 (higher priority)

7. Close the PowerShell.

If the two computers are set up properly, you can install Application Server and other System Platform software, and the OSConfigurationUtility sets up the firewall exceptions appropriately.

If you install Application Software and other System Platform software before configuring the NICs properly, configure the NICs as described in this section and then run the OSConfigurationUtility again. To do this, run the OSConfigurationUtility.exe, located in the C:\Program Files (x86)\Common Files\ArchestrA folder.

To verify that the firewall exceptions are set, open Control Panel and then open the Windows Firewall application. Verify that the executables for the System Platform products you have installed are allowed to communicate through the firewall.