Azure Application Gateway
An Azure service that provides a platform-managed, scalable, and highly available application delivery controller as a service.
1,069 questions
Delay in getting SSE Events when configured via Azure Application gateway
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Vinay
0
Reputation points
We have implemented SSE Server in python. We are using EventSource to subscribe to the SSE server from angular project.
When the SSE Server is running in the local system, when an Event is pushed to the server, the event is getting pushed to the EventSource without much delay.
Problem: When the SSE Server is deployed to VM and configured via Azure Application gateway, when an Event is pushed to the server, there is a delay before the event is getting pushed to the EventSource. Sometimes, the delay is as high as 15 seconds.
When the same SSE Server in VM is configured for direct access via ipaddress, any Event that is pushed to the server is getting pushed to the EventSource without much delay.
Is the delay in Events getting pushed to Event Source when access is configured via Azure Application gateway is happening because of the Azure app gateway? Any settings in the Azure Application gateway that needs to be configured specifically for SSE?
Python version: 3.8
SSE version: sse_starlette v1.3.4
Application gateway Tier used: Standard
Thank you.
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KapilAnanth-MSFT 45,121 Reputation points Microsoft Employee2023-05-03T09:48:39.5866667+00:00 Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.
I understand that Application gateway is adding a 15 sec latency to the data pushed to the backend.
Do you have WAF Enabled on the App Gateway.
- Without looking at the logs, I am afraid we cannot comment on which resource is cauing the latency here.
- Did you check the App gateway AccessLogs?
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- Can you share a log file for the transaction with latency,
- clientResponseTime
- timeTaken
- WAFEvaluationTime
- serverResponseLatency
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- Refer : AccessLog for Application Gateway and WAF v2 SKU
Cheers, Kapil
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KapilAnanth-MSFT 45,121 Reputation points Microsoft Employee
2023-05-04T06:30:22.3566667+00:00 May I know if you got a chance to review my previous comment?
Please let me know if you are facing any challenges or if there are any follow-up questions, I shall be glad to address them.
Thanks,
Kapil
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KapilAnanth-MSFT 45,121 Reputation points Microsoft Employee
2023-05-05T04:52:25.1866667+00:00 Reaching out to check if there are any questions on this.
Please let us know if we can be of any further assistance here.
Thanks,
Kapil
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