Azure SNAT exhaustion - how do I know when it is happening?
For an Azure WebApp, click Diagnose and solve problems, then in search box type snat then click the SNAT Port Exhaustion item which appears as the result of your search.
I just got off the phone with Microsoft Azure support. At this time, there is no way for us as a customer to see SNAT exhaustion without opening a ticket.
I have put in an enhancement request for Microsoft to enable monitoring on it: https://feedback.azure.com/forums/231545-diagnostics-and-monitoring/suggestions/36274288-apim-load-balancer-metrics-to-view-snat-metrics-st
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