Multiple Instances of 4D v18 on Windows 10

I remember reading something, somewhere, that it is now safe to launch the same copy of 4D multiple times without duplicating the application like was required in the past.

1 - Do I remember correctly? I have been launching a single copy of the 4D code multiple instances at a time to connect to multiple 4D servers and have not seen any problems. Just verifying this is safe/OK

2 - If Yes on question 1, then is 4D Server the same on a Windows Server 2016? Can we launch multiple servers on the same physical copy of 4D Server?


Upfront: we strongly recommend to deploy only as “Build Application”. Only with this concept a developer has full control over deployment, about which version the end user will use, allowing to auto update, etc.
So the following text is only true with “build”:

  1. yes. You need to set the option to allow that, see:

  2. No/Yes. You cannot launch several instances of the same build, but you can duplicate the folder and run as many copies (some people name that instances) as you want at the same time. Duplicating the Server application folder allows even to run several different versions at the same time, such as v18.0, v18.1 and v18.2 or a mix with Hotfixes, Nightly Builds, v18 R2, even v17 and v18.
    This allows slow migrations, no need to update all applications at the same time. Each copy will support auto update, to keep them up to date, if wanted.

It’s dangerous to run the same application (same name) in the same Windows session with different versions of 4D : the folder where components and plugins are compressed is exactly the same.
Build app :
C:/Users/username/AppData/Roaming/4D Server/4DC-name/4D/
Engined app :

So, to do that, we have to use different Windows session or different 4DC name.

Please 4D, it would be great to replace the 4D folder by a folder named with the 4D build number.