my customer is connecting 34 UA Client services ( they are going to growth ) coming from the same ip address ( ERP Server ) and subscribe around 10/15 tags each, to an Ignition 8.1 UA Server. When he want to write a tag, he brings up another UA Client connection. All from the same ip. Seems that this behaviour cannot be mitigate from its side. Actually without user/pwd/certificate.
Ignition 8.1 UA Server provides the limit of 100 connection that can be adjusted and "virtually" unlimited, but it seems there is a Rate Limiter of 4 connection coming from the same IP in a time-window of 1000 ms to prevent/detect overload and mainly DoS attack. The UA Client services from ERP seems to go up in the same moment, most of them are discard, and then a retry mechanism of 5 second try to reconnect again ( I don't know if in the same second - need to investigate more ).
To solve the problem, is there any way to "elude", disabile or tweak this function? Thanks in advance, Andrea
This seems like a bad architecture but also we often run into 'it is what it is can you make it work' situations so off the top of my head:
Could you give the ERP additional secondary IPs and then group the clients into different IP connections
Or maybe install a local proxy on the Ignition server as the limiter skips loopback connections. This probably isn't wise as it would defeat the DDOS protection but would probably work.
Thank you guys for your support. @Nol more IPs was in my mind too, need to know if the "services" could be assigned to a specific NIC/IP.
I'll mark as Solved, it seems the programmer is going to rework his services to make just one connection. It will anyway not subscribe to the tags, only READ all of them every 1 seconds.
