Istio envoy 504 gateway timeouts after 15 seconds for outbound connections

Question

Background:

I am using istio 1.2.5

I have deployed istio using helm default profile from the istio documentation by enablin

Answer 1

After lot of hit and trial we got this working.

Reference: https://github.com/istio/istio/issues/16915#issuecomment-529210672

So for any outbound traffic no matter if you have egress gateway or not default timeout is 15 seconds. So, if you want to increase that you need to have a ServiceEntry and a VirtualService that defines the timeout.

ServiceEntry

apiVersion: networking.istio.io/v1alpha3
kind: ServiceEntry
metadata:
  name: external-se-test
spec:
  hosts:
  - slowwly.robertomurray.co.uk
  location: MESH_EXTERNAL
  ports:
  - number: 80
    name: example-http
    protocol: HTTP
  resolution: DNS

VirtualService

apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: slow-ext
spec:
  hosts:
    - slowwly.robertomurray.co.uk
  http:
  - timeout: 30s
    route:
      - destination:
          host: slowwly.robertomurray.co.uk
        weight: 100