istiocircuit-breakerservicemesh

Trigger Istio Circuit Breaker based on % of 5xxErrors

I was reading up the documentation for Istio circuit breaker. I see that for a given interval we can set up a numerical value of consecutive5xxErrors (and check few other settings) for the circuit breaking action to take effect.

I wanted to know if it was possible to somehow do circuit breaking in Istio based on the % of 5xxerrors vs normal connections?

Solution

  • Following on the documentation that you've already found:

    As you can see there are specific fields for the outlierDetection:

    The field that will force the request to not hit particular object is: consecutive5xxErrors.

    As also it can be seen in the documentation:

    Field Type Description Required
    consecutive5xxErrors UInt32Value Number of 5xx errors before a host is ejected from the connection pool. When the upstream host is accessed over an opaque TCP connection, connect timeouts, connection error/failure and request failure events qualify as a 5xx error. This feature defaults to 5 but can be disabled by setting the value to 0. No

    -- Istio.io: Latest: Docs: Reference: Config: Networking: Destination Rule: Outlier Detection

    The value for it is flat and cannot be used as a percentage.

    I found the feature request on the github page of Istio that I think is referencing the feature that you would like to run:

    I'd reckon you could try to use an EnvoyFilter to modify the configuration of Envoy (haven't tested it) as Envoy itself has some fields related to the percentages of failures/successes. The documentation that should help you: