The SSRS service application proxy is not configured. Use the SSRS service application pages to configure the proxy

Issue:
I was getting the below error while rendering SSRS service after installing updates in WFE in SharePoint server.





Solution & Root cause analysis:
When I started doing the root cause analysis I have realized that SSRS service in central admin got stopped. Follow the below steps to see the detailed error message in server logs.
1. Log on to WFE and launch central admin with FARM admin account
2. Navigate to Manage Service Applications under Application management
3. Find your Reporting Services service application and click the name of your service application

4. Click on System Settings

5. Click on Enable remote Errors in Security section

Once you once enable this in Central admin we need to enable the same setting at Site Collection level.
1. Open the site collection which are experiencing SSRS rendering issue
2. Click on Site Action and click on Site Settings
3. Click Reporting Services Site Settings in the Reporting Services group

4. Click Enable remote errors in local mode check box

Ok with this we have enabled the option of logging detailed error in server logs.
Now if you refresh the page where you are getting the above error it will log a detailed error message in server log file. It will be as follows:

As the error message shows we need to enable the reporting services service in central administration.

The SSRS service application proxy is not configured sharepoint 2016

Once I restart the service SSRS service is rendering as expected.