From dee8c11088a8ce43e9010de630cf211a4b7e67a8 Mon Sep 17 00:00:00 2001 From: Sachin Holla Date: Sat, 31 Jul 2021 11:57:36 +0530 Subject: [PATCH] Overview section update for Telemetry_Subscribe_Paths.md This document serves as a short HLD to list YANG modules/paths that support ON_CHANGE subscription and wildcard paths for otehr subscribe modes. Updated the overview section to capture these info. --- .../Telemetry_Subscribe_Paths.md | 33 +++++++++++++++++-- 1 file changed, 30 insertions(+), 3 deletions(-) diff --git a/manageability/mgmt-framework/Telemetry_Subscribe_Paths.md b/manageability/mgmt-framework/Telemetry_Subscribe_Paths.md index f4694986ef62..cd5dd9773a1a 100644 --- a/manageability/mgmt-framework/Telemetry_Subscribe_Paths.md +++ b/manageability/mgmt-framework/Telemetry_Subscribe_Paths.md @@ -1,10 +1,13 @@ # Telemetry Subscribe YANG Paths -This document lists Telemetry ON_CHANGE enabled or disabled YANG paths. +This document lists Telemetry ON_CHANGE and wildcard path subscription enabled YANG paths. ## Table of Contents - [1 Overview](#1-overview) + - [1.1 Background](#11-background) + - [1.2 Scope](#12-scope) + - [1.3 ON_CHANGE supported vs not supported](#13-on_change-supported-vs-not-supported) - [2 OpenConfig YANG Modules](#2-openconfig-yang-modules) - [2.1 openconfig-network-instance](#21-openconfig-network-instance) - [2.1.1 IGMP Snooping](#211-igmp-snooping) @@ -15,6 +18,7 @@ This document lists Telemetry ON_CHANGE enabled or disabled YANG paths. | Rev | Date | Author | Change Description | |-----|-------------|--------------------|----------------------------------------------| | 0.1 | 05/18/2021 | Sachin Holla | Initial version | +| 0.2 | 07/30/2021 | Sachin Holla | Overview section update | ## References @@ -26,13 +30,35 @@ https://github.com/openconfig/reference/blob/master/rpc/gnmi/gnmi-specification. ## 1 Overview -This document intends to list Telemetry ON_CHANGE disabled or enabled YANG paths. +### 1.1 Background + +SONiC telemetry server supports SAMPLE, POLL and ONCE subscriptions for any YANG path as long as +the subscribed path does not include any wildcard keys. +ON_CHANGE subscription and wildcard path support (for any subscription type) requires changes in +both infrastructure and the individual app code. +Infrastructure changes are implemented in SONiC 3.2.0 and 4.0.0 releases. +But not all apps are ready for it yet. +This document intends to list YANG modules that have been qualified by app teams +for wildcard paths and ON_CHANGE subscription. + +### 1.2 Scope + +This document lists YANG modules or paths that support ON_CHANGE subscription and +wildcard path subscription for all subscription types. +Paths that do not support ON_CHANGE subscription on purpose are also called out here. + However listing every YANG path and its preference is not practical. Hence this document lists YANG modules and captures the special cases for each. Eg. if ON_CHANGE is not supported for only few paths, then it can just list the ON_CHANGE unsupported pats. +### 1.3 ON_CHANGE supported vs not supported + +Not all YANG paths will support ON_CHANGE subscription. +YANG nodes representing non-DB data or frequently changing data will not support ON_CHANGE. +App teams will capture this infomation in this document. Note that if ON_CHANGE is not supported for a node, ON_CHANGE subscription cannot be supported for its child paths or paths poiting to its parent containers. +This is implicit and apps may omit child node/leaf paths for brevity. But SAMPLE or TARGET_DEFINED subscriptions are supported. Few examples with a simplified openconfig-interfaces YANG model: @@ -137,7 +163,8 @@ openconfig-network-instance:network-instances/network-instance[name=default]/pro ### 2.2 openconfig-tam -All paths of openconfig-tam module supports ON_CHANGE except for the following paths. +All paths of **openconfig-tam** module supports wildcard path subscriptions. +ON_CHANGE subscription is also supported for all paths except for the following: ```text /openconfig-tam:tam/flowgroups