Merge pull request #298250 from jaesoni/update-conn-drain-remove-unhealthy

Update conn drain - remove unhealthy scenario

Author: prmerger-automator[bot]

articles/application-gateway/configuration-http-settings.md

@@ -5,7 +5,7 @@ services: application-gateway
 author: greg-lindsay
 ms.service: azure-application-gateway
 ms.topic: concept-article
-ms.date: 03/19/2025
+ms.date: 04/14/2025
 ms.author: greglin
 ---
 
@@ -34,9 +34,7 @@ The default affinity cookie name is *ApplicationGatewayAffinity* and you can cha
 
 ## Connection draining
 
-Connection draining helps you gracefully remove backend pool members during planned service updates. It applies to backend instances that are 
-- explicitly removed from the backend pool, or
-- reported as unhealthy by the health probes.
+Connection draining helps you gracefully remove backend pool members during planned service updates. It applies to backend instances that are explicitly removed from the backend pool.
 
 You can apply this setting to all backend pool members by enabling Connection Draining in the Backend Setting. It ensures that all deregistering instances in a backend pool don't receive any new requests/connections while maintaining the existing connections until the configured timeout value. This process is also true for WebSocket connections.
 

articles/application-gateway/features.md

@@ -5,7 +5,7 @@ services: application-gateway
 author: greg-lindsay
 ms.service: azure-application-gateway
 ms.topic: concept-article
-ms.date: 03/24/2023
+ms.date: 04/14/2025
 ms.author: greglin
 ---
 
@@ -104,15 +104,11 @@ For more information, see [WebSocket support](application-gateway-websocket.md)
 
 ## Connection draining
 
-Connection draining helps you achieve graceful removal of backend pool members during planned service updates or problems with backend health. This setting is enabled via the [Backend Setting](configuration-http-settings.md) and is applied to all backend pool members during rule creation. Once enabled, the application gateway ensures all deregistering instances of a backend pool don't receive any new requests while allowing existing requests to complete within a configured time limit. It applies to cases where backend instances are:
-- explicitly removed from the backend pool after a configuration change by a user, or
-- reported as unhealthy by the health probes
-
-The only exception is when requests continue to be proxied to the deregistering instances because of gateway-managed session affinity. 
+Connection draining helps you achieve graceful removal of backend pool members during planned service updates or problems with backend health. This setting is enabled via the [Backend Setting](configuration-http-settings.md) and is applied to all backend pool members during rule creation. Once enabled, the application gateway ensures all deregistering instances of a backend pool don't receive any new requests while allowing existing requests to complete within a configured time limit. It applies to cases where backend instances are explicitly removed from the backend pool after a configuration change by a user.
 
 The connection draining is honored for WebSocket connections as well. Connection draining is invoked for every single update to the gateway. To prevent connection loss to existing members of the backend pool, make sure to enable connection draining.
 
-For information on time limits, see [Backend Settings configuration](configuration-http-settings.md#connection-draining).
+For more details, see [Backend Settings configuration](configuration-http-settings.md#connection-draining).
 
 ## Custom error pages