In general, HTTP 5xx responses indicate server issues. However, when creating a distributed web service with Azure App Services, some number of 5xx responses are expected. Blue Matador watches the Http5xx metric for the number of 5xx responses returned by your app service, and creates events when this metric is anomalous. A sudden spike in the number of 5xx responses can be the result of the following:

    • Deploying new code that contained a bug
    • Errors returned by upstream services that your application depends on
    • Your application is overwhelmed by the amount of traffic it is receiving
    • Issues in the configuration for your app service

    HTTP 5xx responses usually result from problems specific to your application, but the general process for troubleshooting the problem is the same for most applications. First, enable and check access logs for your app service. Look for the endpoint or endpoints that are returning the 5xx status codes. Next, scan the logs emitted by that endpoint (with the log management solution your organization uses) for exceptions or other errors that could be resulting in 5xx responses. Finally, fix the issue and deploy the solution.