Hi Andy,
Thank you for getting back to my post.
Node A,B and C are in same cluster and there is no XDCR setup as all three servers located in same network.
Yes, Node A,B and C all three servers have sync gateway installed and three nodes have same bucket name and same cluster server store.
Internal sync gateway API updates documents on Node A and then those updates are pushed to Node B and C by Node A. All three servers are internal DMZ servers and i am using hardware Load Balancer for sync gateway.
Please see attached flow process of my setup.
Thanks,
Karunakar