Identical systems IP

[Operaghost]

I know im continuing to add detailed information i should have started with..
I can get remote access for programming through the HMI. It has it built in.
This is why I wasn't going to use an E*w*n this time around. By using the HMI independently in each system as access if IPs are the same i will not know which system im in, unless I throw a comment in one of the programs maybe, then i can check.

I also am using L3x controller, which has dual IP, which i planned on leaving A2 open so they could use it for their plant whenever they decide to.

So I would still recommend changing IP addresses using whatever scheme makes the most sense. That way when the day does come that they all need to talk to each other, they will be ready.

I like the idea of keeping the last octet consistent for each device. So for each system the PLC is always at x.x.x.10 while maybe the HMI is at x.x.x.50. But it can be trickier since those would be considered separate subnets. Connecting them from your PC might be a little more involved.

Your original idea of using 10, 20, 30, etc.. for one system and 11, 21, 22, etc.. for the next system works too. And everything is on one subnet so connecting to it is very easy.

OG

 

[andrewwei]

All great responses to think about thank you.
The systems will not talk to each other directly.
Each system has its own set of ethernet switches.


I do not have a NAT currently for each system nor are we responsible for networking to the plant.
But i would like to make it as seemless as possible for them when they decide to hook to the plant.

In the automobile industry, it is very common to have identical or almost identical systems. They normally put them in different subnets. Like system 1 is on 192.168.1.0 network. and system 2 is on 192.168.2.0 network.

 

[bill4807]

So I would still recommend changing IP addresses using whatever scheme makes the most sense. That way when the day does come that they all need to talk to each other, they will be ready.

I like the idea of keeping the last octet consistent for each device. So for each system the PLC is always at x.x.x.10 while maybe the HMI is at x.x.x.50. But it can be trickier since those would be considered separate subnets. Connecting them from your PC might be a little more involved.

Your original idea of using 10, 20, 30, etc.. for one system and 11, 21, 22, etc.. for the next system works too. And everything is on one subnet so connecting to it is very easy.

OG

Thank you for the responses.

 

[bill4807]

In the automobile industry, it is very common to have identical or almost identical systems. They normally put them in different subnets. Like system 1 is on 192.168.1.0 network. and system 2 is on 192.168.2.0 network.

Ok thats interesting, and pretty easy to follow as well.

 

[bill4807]

I would do this as well. We have a lot of identical machines and the PLC is always node number 1, HMI's are always 50, barcode readers are always 130, etc.

Yes i keep the devices the same when i have done identical systems in the past.
The last one was identical IPs just like you stated.
But the customer requested that, so easy decision for me.

 

[bill4807]

I would use different IP addresses.
if you ever connected them to a plant network, nothing would work, they have the same ip address and create a conflict on the network. i had that happen to me, someone in maintenance powered up an old display board that had the same ip address as a barcode scanner. i had to create a new ip network for all our scanners.
james

Yes if whomever connects it doesn't know then big mess i agree.

 

[plvlce]

With the dual IP controllers we have started using identical setups for the machines' internal networks. Since it is a separate network from the plant connection there's no real risk of duplicate IP issues.

 

[bill4807]

With the dual IP controllers we have started using identical setups for the machines' internal networks. Since it is a separate network from the plant connection there's no real risk of duplicate IP issues.

Yes thats what i figured and why i leave it open for them to use. I just am never on the IT side to see how it ends up working.
So when you remote in - how do you know what system you are in/connected to.

 

[plvlce]

Yes thats what i figured and why i leave it open for them to use. I just am never on the IT side to see how it ends up working.
So when you remote in - how do you know what system you are in/connected to.

Sorry if it wasn't clear -- I'm one of the guys inside the plant, not remoting in. That means I get to just use the plant network side IP address, or am at the machine physically and directly plugged in.

Each controller has a distinct name though, so you can see in RSLinx whether you're looking at the right one.

 

[mk42]

In the automobile industry, it is very common to have identical or almost identical systems. They normally put them in different subnets. Like system 1 is on 192.168.1.0 network. and system 2 is on 192.168.2.0 network.

I really prefer this kind of setup to NAT. You can still have security (firewalls in the IT router connecting all the subnets), but it allows for easy networking between devices.


NAT has always felt like a bandaid to me: useful for allowing networking into an old unconnected cell, but not to be relied on if you're designing from scratch. I had one time though that it 100% made sense, where the customer actually needed the cell to change it's apparent IP often as it got moved, and so the PLC could reconfigure the NAT switch as needed.

 

[JesperMP]

I see the need for NAT routers when machines are 100% standardized, and you cannot make a custom program with different IP addresses for each machine in the same location.

 

[Phil Buchanan]

If you have a lot of identical machines I would keep the IP addresses the same from machine to machine for consistency, then use a NAT device in each panel. Only map the devices from each machine that you would actually need to connect to remotely, and give them unique IP addresses in the NAT table of the NAT device. Your IT guy will thank you.

Above is a good solution but depends on your other network config and needs and how you plan to connect remotely.

 

[andrewwei]

System1: 192.168.1.0 Sub mask 255.255.255.128
System2: 192.168.1.128 Sub mask 255.255.255.128

 

[I_Automation]

I have worked on a line of laminating machines made in Italy and every one has the same IP address for the PLC and the HMI. Also they all use the same password. They presume their machines will either not be online or one customer won;t own more than one of their machines.