I just moved my cluster from AWS EC2 to Google Compute, and looking at the logs it seems there are constant network issues.
This happens with 2 specific nodes, several times a day.
It starts with the error:
master left (reason = failed to ping, tried [3] times, each with maximum [30s] timeout), current nodes: nodes:
Checking the logs it doesn't seem like they are restarting (running with docker), just disconnecting and reconnecting.
The networking tab in VM instance details
is not that helpful.