Add info on clustered RPCs to controller dev-guide

Change-Id: Ib8eee716b5335a353b1bc11a55d675ace1a2bb04
Signed-off-by: Tomas Cere <tcere@cisco.com>

diff --git a/docs/developer-guide/controller.rst b/docs/developer-guide/controller.rst
index 99000069c1b649a32f01f049f7c7cb66928e01be..1eccd7ff813bf3cc829be07ca4fc58c72925dd86 100644 (file)
--- a/docs/developer-guide/controller.rst
+++ b/docs/developer-guide/controller.rst
@@ -841,6 +841,17 @@ Line 112: We register salFlowService1 as implementation for nodeOne.
 The salFlowService1 will be executed only for RPCs which contains
 Instance Identifier for foo:node:1.
 
+RPCs and cluster
+^^^^^^^^^^^^^^^^
+
+In case there is is only a single provider of an RPC in the cluster
+the RPC registration is propagated to other nodes via Gossip protocol
+and the RPC calls from other nodes are correctly routed to the
+provider. Since the registrations are not expected to change rapidly
+there is a latency of about 1 second until the registration is reflected
+on the remote nodes.
+
+
 OpenDaylight Controller MD-SAL: RESTCONF
 ----------------------------------------