I’m trying to use EventStore but we have a problem. We have only two datacenters and we must continue to work if one of the two datacenters does not respond (LAN issue, etc…).
If we create two instance of EventStore (one on each datacenter), we cannot use clustering because we do not have 3 instances (2n+1).
But I’ve tried the following and it seems to work :
Lets say we have instances 1 and 2 on the first datacenter and instances 3 and 4 on the second datacenter.
I’ve declared that instance 1 is in a three nodes cluster with instance 2 and instance 3
I’ve declared that instance 2 is in a three nodes cluster with instance 1 and instance 4
I’ve declared that instance 3 is in a three nodes cluster with instance 4 and instance 1
I’ve declared that instance 4 is in a three nodes cluster with instance 3 and instance 2
When my four instances are up, I’ve a master, two slaves and one clone. With this configuration, I can have 2 instances down, the 2 up instances still work, replicate, …
When I restart the down instances, the down instances update their database.
Is it a supported scenario or am I lucky this works ?