Azure Cosmos DB is a highly-scalable distributed database service. The nature of Cosmos DB means that sometimes requests will return HTTP status codes in the 500 range when operations do not succeed. Blue Matador automatically monitors the number of requests with each status code using the TotalRequests metric so you can debug your usage of Cosmos DB and correlate issues with other events in your system.
An Internal Server Error means an unexpected error occured with the Cosmos DB service. These errors may be transient, but if they persist then you should contact Azure Support and check the Azure Status Page for an outage in the regions you are using.
A 503 error means that the Cosmos DB service could not be reached. This can be due to either network issues or issues with the Cosmos DB service itself. Requests should be retried, and you should contact Azure Support and check the Azure Status Page for an outage in the regions you are using.
To mitigate the impact of regional outages, you can configure multi-master writes. This can reduce latency for applications that run in multiple regions, and if regional outages occur writes can be redirected to another region.