Overview of Istio traffic management concepts and exam-focused module covering sidecars, virtual services, destination rules, ingress/egress, resilience techniques, traffic routing, mirroring, and ambient mode
This is the most important module and the longest, so let’s diveinto what we’re going to cover in this module.This module examines sidecars, focusing on the resource and its default behavior.Virtual services, possibly the most important resource in the Istio service mesh.I would say that around 30 to 35% of all the questionsyou’re going to get in the ICAexam will involve a virtual service.And if we’re talking about importance, I guess secondon the list would be DestinationRules.This is a must-know for the ICA exam.
This is where splitting traffic is configured.We’ll talk about exposing applications to the public using ingress gateways andalso outgoing traffic using egress gateways.We’ll talk about how we can introduce external services, something like adatabase or a web app, and bring itinto the service mesh using ServiceEntries.We’ll talk about the pros and cons to various release methods andshow you a better way called Istio traffic mirroring or A/B testing.We’ll be talking about the issues that can happen in a microservicesstack and how they can be avoided using circuit breaking.We’ll look at how we can preventcascading failures when those bottlenecks happen.Resilience isn’t just about avoiding issues, but more about being preparedfor them when they do happen.And fault injection is the answer.We’ll look at intentionally implementing delays and abortsto see how the application behaves.We’re going to be using timeouts and retries asa safety measure for those errors.And finally, after we talked about all of these different Istio resources,we’ll have a look at how to set up ambient mode and
go over a demo on how to use layer 4 traffic usingztunnels and layer 7 traffic using the waypoint proxies, using HTTPRoutes.Although I should mention again that none of this is going tobe in the actual ICA exam.And by this, I mean the actual ambient mode.So we’re not going to deep diveinto, you know, HTTPRoutes and EnvoyFilters.We are going to cover ambient mode, but the examdoes not go in too deep.So we’re not going to go in too deep into ambient mode.And, you know, there’s a lot to cover in this module.