EMS Channels in a Cluster

When eFTL servers cooperate in a cluster, their corresponding EMS channels do not forward messages across the cluster. Instead the EMS server forwards messages to the corresponding channels in each server.

The diagram illustrates a cluster of two eFTL server processes. The purple arrow indicates that when PubB1 sends a message, Svr1 translates it and forwards it the EMS server. The EMS server forwards it in two directions:

  • The downward black arrow indicates delivery to EMS subscribers, such as SubB2.
  • The upward blue arrows indicate delivery to channel B of both eFTL servers, which translate the message again, and forward it to eFTL subscribers, such as SubB1 and SubB3.

When EMS publisher PubB2 sends a message, the EMS server forwards it over same upward paths.

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