Once the networks have been configured, the next step is to ensure the computers and devices on either side of the firewall can communicate with each other. It is assumed that you have worked with your IT department to complete the firewall configuration worksheets and that you have set up the necessary routing information on the external workstations and routers. Further, it is assumed that the DeltaV workstations' NICs have the default gateway defined as the firewall's IP address. We will use the standard network ping command to verify that the workstations on either side of the firewall can communicate with each other. Before testing, you will put the firewall in Allow all mode so you can easily ping between the computers or devices. The firewall's Allow all mode allows any computer on either side of the firewall to communicate through the firewall. The firewall essentially acts as a simple router and does not block any communications. During operation the Allow all mode is used only if there are problems with critical applications that must remain working. The firewall is set to Allow all mode temporarily as the problem is resolved.
We will use Allow all mode during setup so that we can test communications between the computers on either side of the firewall so there is no chance of the firewall configuration impacting the communications.
In Allow all mode, there is no logging and no connections are listed unless you create protection rules to allow pinging between computers. As rules are not necessary to verify communications we will not build rules now.