Without violating your confidentiality, can you share what version of ES you experienced these failures with? I have also experienced this first hand, but since 0.9x and 1.0x a TON of work has been done on both OOM (one of the leading causes of split brain scenarios) and split-brain from network partitioning. As I mentioned below, all of these issues are being addressed in an open and transparent way, and while there's still work to be done, a non-trivial amount of progress has already been made. I hope you can share at least some about your experiences.