I am reviewing a proposal where a Compact Logix processor needs to be on three (3) separate Ethernet networks. For the sake of argument, say that these networks will will be these IP address ranges: 192.168.x.x, 172.16.x.x, and 10.x.x.x.
In the past we have generally used Control Logix, where each network gets its own ENxT module. All is good with this approach, but that is not an acceptable option for (non-technical) reasons in this case.
This proposal calls for a 5370 processor, which only has a single IP address. In these cases we use one of the Rockwell NAT devices for a second network. When the integrator was questioned about the third network, the answer was to "just" add a second 1783-NATR to the 192.168 network.
This has me a bit nervous about whether it will actually work. For example, when using a single NAT on a private network, its private-side address is the gateway for the devices on the network. This implies one-NAT-per-private network to work as expected (implicit messaging, OPC, remote program access).
It's not too late to re-design with a 5380, but this also has resistance for non-technical reasons.
Questions:
. Has anyone ever used multiple Rockwell NAT devices to provide access to a single private network from more than one external network?
. Can the dual IP addresses of a 5380 be used, functionally, like two ENxT modules in a Control Logix system (e.g., do they separately appear in the I/O tree)? If so, will the NAT allow access to the processor from the third network?
. Not that I want to go here: But is there a way to accomplish this more-than-two network capability for a 5370 processor using Stratix switch(es) or third-party equipment?
In the past we have generally used Control Logix, where each network gets its own ENxT module. All is good with this approach, but that is not an acceptable option for (non-technical) reasons in this case.
This proposal calls for a 5370 processor, which only has a single IP address. In these cases we use one of the Rockwell NAT devices for a second network. When the integrator was questioned about the third network, the answer was to "just" add a second 1783-NATR to the 192.168 network.
This has me a bit nervous about whether it will actually work. For example, when using a single NAT on a private network, its private-side address is the gateway for the devices on the network. This implies one-NAT-per-private network to work as expected (implicit messaging, OPC, remote program access).
It's not too late to re-design with a 5380, but this also has resistance for non-technical reasons.
Questions:
. Has anyone ever used multiple Rockwell NAT devices to provide access to a single private network from more than one external network?
. Can the dual IP addresses of a 5380 be used, functionally, like two ENxT modules in a Control Logix system (e.g., do they separately appear in the I/O tree)? If so, will the NAT allow access to the processor from the third network?
. Not that I want to go here: But is there a way to accomplish this more-than-two network capability for a 5370 processor using Stratix switch(es) or third-party equipment?
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