I had several questions regarding the multiple redundancy options. While there are posts on the forum, they only address one specific topic leaving me to wonder how others might do things.
Here is my understanding of the options and questions.
1. Ignition Standard Redundancy pricing option - This is a redundant server in an Active/Passive configuration. The documentation states that both servers should be located together. The servers should not be split between on-premise and the cloud.
I assume that this is because communication errors are likely which would cause a failover to occur and possibly bad data to enter the system.
If the documentation is followed, this allows for maintenance of a server. However, if the servers are located in the same rack and something happens to the rack, then both servers are down. Some manufacturing sites are limited in network infrastructure, space, and/or are challenging environments with the product.
If it were not for the documentation, I would have preferred to have an on-premise and cloud Active/Passive configuration. Although this would not cover if the rack went down alongside the firewalls for the internet.
Does anyone do the Ignition redundancy between on-premise and the cloud?
2. Ignition Edge - I understand the concept of this product in small environments that require a couple of screens. I don’t understand why people use this in large environments when they also have Ignition servers. It seems expensive and hard to maintain.
In one post, someone mentioned they have an entire Ignition server setup and each HMI also had an Edge license. Since the Edge project has to be developed separately, this seems like a waste of time.
If you are a user that has an Ignition server, why do you also use Edge? What is the use case?
3. Local Client Fall-Back - Supposedly, one can buy a single vision client Ignition package. If the central server fails, then it fails back to an Ignition server on the local computer.
If your network or main racks fail, this has a chance of providing local control if that part of the network is still good.
If I understand correctly, this option still requires a project on the local machine. So this means that the project must be copied from the central server to the local computers when there are updates?
EAM can copy projects over to keep them in sync?
Are there folks who are doing this? Or are you using other methods?
- Active/Active Configuration - Let’s say I have the exact same full Ignition licenses with servers located on-premise and the cloud. The idea being that if I lose one server, the other can take over.
Without any changes, can I simply copy the project over to each server and have it work? Perhaps, this is done manually or perhaps this is done with EAM?
Or will changes need to be made no matter what to make it work on each server?
How would a tag historian work in this case? Would I end up with double data and/or bad data?
- What kind of methods are you using to keep your plant running?