Learn how easy it is to connect to a Do-more PLC that is behind a VPN router in this brief step by step tutorial! Includes and overview of how VPN routers work.
A Virtual Private Network – or VPN - is a great way to access your Do-more PLC remotely. And it’s super easy to use with the Do-more Designer software, but before we do that, let’s backup and take look at the big picture. Here’s our PC with Do-more Designer Software and we want to connect to a Do-more PLC out on the internet someplace. With a VPN, you typically have a router that the Do-more PLC is behind that acts as a VPN server. Then over here you either have a dedicated VPN Box – which is just a fancy router - that connects to the VPN router to on the internet or a regular router and a client app on your PC that connects to that VPN router. We’re going to use this software approach in this demo and I’m using a popular Cisco VPN Client to do it. Using the VPN client app you create a connection to the VPN router that your Do-more’s behind using your network specifics. I’ve already created one using my VPN networking details for our demo. The IP Address is blurred out because this is AutomationDirect’s VPN test network and we really don’t need a bunch of folks messing with it. Once you have that setup, you just connect the client app to the VPN router. It will take a few seconds to establish a secure connection. Keep in mind I’m just showing you this to give you a feel for how to get access to a typical VPN router. Your network will probably be different so work with your IT guys to get access to your VPN – AutomationDirect’s tech support can’t help you with that end of things. But, the good news is, once you DO establish the connection to your VPN router, connecting to the Do-more PLC that’s behind that router is easy. Start Do-more Designer. Start a new project. Give it a name. We want this series of Do-more and we’ll be using an Ethernet CPU. Now we just connect to the PLC like we would any local Do-more PLC – PLC, Connect. We want to add our new VPN link. Normally I would hit this Link Editor button right now to create that link, but I want to show you why so we’ll hit next and walk down that path for a bit. Select Ethernet and hit next. This is fine. So normally we would just select the Ethernet adapter we want to use, in this case it’s the new Cisco VPN adapter we just created, right? And we would expect to see a list of all the Do-mores on that network. But there aren’t any here – why not? Well, because you can’t auto detect Do-mores on the other side of a VPN. The stuff Do-more Designer needs to detect those PLCs is hidden by the mechanics of the VPN. So we hit this link editor button – which we could have hit in the previous step – to tell Do-more Designer how to find the Do-more PLC. Give it a name. We want this kind of Do-more and an Ethernet capable CPU. The Do-more’s IP address goes here – NOT the router it is behind. This is the IP Address of the Do-more that’s behind the VPN router. While we are here let’s make sure the default Do-more port number is correct – this 28784 – that’s perfect. When using a VPN this always needs to be this number which is the listening port on the Do-more, assuming you are using the primary Ethernet port. If you are using the secondary Ethernet port, you can actually configure the Do-more with any port number you want. We’re using the primary port so we have to use this one. Go ahead and double check that we’re using the Do-more protocol. It should be but it can’t hurt to be sure. You may find that you need to adjust the timeout. Especially if your Ethernet messaging has to travel through lots of routers to get to the Do-more. So how do you know what to put here? Easy. Once your VPN is connected, just go to the command prompt and ping the Do-more. That’s how long it typically takes to get messages between my PC and the Do-more behind the VPN router I’m using. If I ping the Do-more that Host engineering setup for anyone to try – it’s in in Tennessee, I‘m in Georgia – looks like the ping time is about three times as long. Regardless this 1000ms time out should be MORE than enough to cover either of those. So all we did was give it a name, selected Ethernet, entered the IP Address of the Do-more that is behind the VPN router, verified the port number, protocol, and timeout. Looks good, so accept that. So we select that link and just like that we are now talking to a Do-more over a VPN that is out on the internet someplace. Easy. If you need any help with the Do-more PLC please contact AutomationDirect’s FREE award winning tech support during regular business hours. But please don’t call them about networking or VPN stuff – they aren’t setup or trained to help you with your network. And don’t forget the forums – there are lots of folks there that love to share their years of experience. Again, just don’t post any questions directed at AutomationDirect’s tech support team there – they don’t monitor the forums on a regular basis.