I am a newbie to the Percona cluster, please bear with me. I created a 3 node cluster over 2 geo-locations. Location A has 2 nodes with HAProxy load balancer, where Loc B has just 1 node. Everything seems fine. The web-app that makes use of it is a PHP, OLTP-type home grown application with off-course the typical PK-FK relations. Under a single MySQL box on the Innodb engine everything runs fine.
My question: If the network connection between Loc A and B is severed for some time and on both Loc A and B independant data inserts take place via the web-app, how does the cluster when the network connection re-establishes prevent/resolve key collision and subsequent bad pk-fk relations?
Thank you for your insight