From fc24c20e1fc34693db9d4268d123f5616c07eec4 Mon Sep 17 00:00:00 2001
From: sachendras <44847441+sachendras@users.noreply.github.com>
Date: Fri, 27 Sep 2024 08:43:15 -0700
Subject: [PATCH 1/3] Update gNOI.bgp.proto

Current gNOI.BGP proto lacks guidance on how the ClearBGPNeighborRequest must be handled. As per RFC
---
 bgp/bgp.proto | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/bgp/bgp.proto b/bgp/bgp.proto
index 1a19702..10c9127 100644
--- a/bgp/bgp.proto
+++ b/bgp/bgp.proto
@@ -39,7 +39,8 @@ message ClearBGPNeighborRequest {
   enum Mode {
     SOFT = 0;         // Send route-refresh and reapply policy.
     SOFTIN = 1;       // Re-apply inbound policy on stored Adj-RIB-In.
-    HARD = 2;         // Teardown and restart TCP connection.
+    HARD = 2;         // Teardown, restart TCP connection, Send Cease notification (code 6) with subcode 9 and flush all routes.
+    GRACEFUL = 4;     // Teardown, restart TCP connection, Send Cease notification (code 6) with subcode 4 and dont flush routes.
   }
   Mode mode = 3;       // Which mode to use for the clear operation.
 }

From 0ee80a1a76d513ca643135d0f298047db7a5aef5 Mon Sep 17 00:00:00 2001
From: sachendras <44847441+sachendras@users.noreply.github.com>
Date: Fri, 27 Sep 2024 08:57:29 -0700
Subject: [PATCH 2/3] Update gNOI.bgp.proto

Current gNOI.BGP proto lacks guidance on how the ClearBGPNeighborRequest.Hard must be handled. As per RFC4486, code6 subcode 4,
```If a BGP speaker decides to administratively reset the peering with a neighbor, then the speaker SHOULD send a NOTIFICATION message with the Error Code Cease and the Error Subcode "Administrative Reset".``` which basically leaves implementations to make a choice if they should "reset TCP connection" and "Flush all routes OR not Flush all routes". Hence in rfc8538#section-3.2 for GR a new subcode 9 called `HARD RESET` was introduced to clear such ambiguities so the GR process can be handled more predictively.
Having said that, the gNOI.ClearBGPNeighborRequest API must also have 2 options for reseting a TCP connection to match the RFC. The `GRACEFUL` option introduced in this pull expects sending subcode 4 and the existing `HARD` option expects sending subcode 9 so the GR behavior can be accurately handled.
---
 bgp/bgp.proto | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bgp/bgp.proto b/bgp/bgp.proto
index 10c9127..7e7c3e3 100644
--- a/bgp/bgp.proto
+++ b/bgp/bgp.proto
@@ -40,7 +40,7 @@ message ClearBGPNeighborRequest {
     SOFT = 0;         // Send route-refresh and reapply policy.
     SOFTIN = 1;       // Re-apply inbound policy on stored Adj-RIB-In.
     HARD = 2;         // Teardown, restart TCP connection, Send Cease notification (code 6) with subcode 9 and flush all routes.
-    GRACEFUL = 4;     // Teardown, restart TCP connection, Send Cease notification (code 6) with subcode 4 and dont flush routes.
+    GRACEFUL = 4;     // Teardown, restart TCP connection, Send Cease notification (code 6) with subcode 4.
   }
   Mode mode = 3;       // Which mode to use for the clear operation.
 }

From a5ab33f78abe32de5e3c678c4dee7daaf92a05c8 Mon Sep 17 00:00:00 2001
From: sachendras <44847441+sachendras@users.noreply.github.com>
Date: Fri, 27 Sep 2024 13:46:33 -0700
Subject: [PATCH 3/3] Update gNOIbgp.proto

Update to be more accurate and match the RFC requirements in rfc8538#section-3.1 for subcode9.
---
 bgp/bgp.proto | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/bgp/bgp.proto b/bgp/bgp.proto
index 7e7c3e3..8136829 100644
--- a/bgp/bgp.proto
+++ b/bgp/bgp.proto
@@ -39,7 +39,11 @@ message ClearBGPNeighborRequest {
   enum Mode {
     SOFT = 0;         // Send route-refresh and reapply policy.
     SOFTIN = 1;       // Re-apply inbound policy on stored Adj-RIB-In.
-    HARD = 2;         // Teardown, restart TCP connection, Send Cease notification (code 6) with subcode 9 and flush all routes.
+    HARD = 2;         // Teardown, restart TCP connection, Send Cease 
+    // notification (code 6) with subcode 4. However, if the "N" bit for 
+    // Graceful-Restart" is set, then encapsulate the original Notification
+    // message in the data portion of the Subcode 9 message as per 
+    // rfc8538#section-3.1 and also Flush the routes.
     GRACEFUL = 4;     // Teardown, restart TCP connection, Send Cease notification (code 6) with subcode 4.
   }
   Mode mode = 3;       // Which mode to use for the clear operation.