[keycloak-user] Keycloak clustering in AWS

I am trying to setup keycloak cluster with a shared database in AWS environment. I followed all steps mentioned on this link: http://keycloak.github.io/docs/userguide/keycloak-server/html/clustering.... Keycloak nodes are AWS EC2 and shared database is AWS RDS. How does the keycloak instances identify each other in cluster in AWS (how does multicast work in a AWS VPC)? Has anyone tried this before? Any references or things to take care of list would be great. Thank you, Riddhi Rathod