How to Connect to a Remote Do-more PLC Behind a VPN

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..

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