static boolean isRemoteReplica(RouterConfig routerConfig, ReplicaId replicaId) {
    return !routerConfig.routerDatacenterName.equals(replicaId.getDataNodeId().getDatacenterName());
  }
Checks if the given {@link ReplicaId} is in a different data center relative to a router with the
given {@link RouterConfig}
@param routerConfig the {@link RouterConfig} associated with a router
@param replicaId the {@link ReplicaId} whose status (local/remote) is to be determined.
@return true if the replica is remote, false otherwise.
ambry-router/src/main/java/com/github/ambry/router/RouterUtils.java