ISTIO

Introduction

Service Mesh

Istio Architecture

Istio features

Trafic Management

Gateway

 VirtualService
 

API gateway vs Service Mesh

North-south traffic for Api gateway,

East-west traffic for service Mesh

Service Mesh : DP/CP

Envoy

Features :Telemetry ;Trafic management; Load balancing; Gateways; Fault injection; Circuit breaker;Mutual TLS; Dark release

Ambient Mesh (New)

 

 

 

 

Observability  Monitoring  Tracing  

Logging

Metrics

TraceSpan

LogEntry

Capturing Telemetry headers (OpenTelemtry)

SECURITY

Updates

  • Policy and Meshpolicy are removed since istio 1.6.0

    use PeerAuthentication instead 
apiVersion: security.istio.io/v1beta1
kind: PeerAuthentication
metadata:
  name: default
  namespace: default
spec:
  selector:
    matchLabels:
      app: myApp
  mtls:
    mode: STRICT / PERMESSIVE / DISABLED

Composition

  • Istio core

  • Istiod

  • Ztunnel

  • Ingress gateways

  • CNI plugin

Refer to the latest getting started with ambient mesh doc for updated instructions.

Composition

CNI plugin 

Is responsible for detecting which application pods are part of ambient and configuration the traffic redirection between them and the ztunnel
The CNI DaemonSet on each node constantly watches for pods (on the same node) that are running in ns whith the "istio.io/dataplane-mode=ambient" label
If a pod is detected, it applies iptables redirect rules to redirect all the outgoing and incoming traffic from/to the pod to the ztunnel running on the same node.

Ztunnel

Ztunnel

Client

web-api

Istiod

mTLS

Layer 4 aka transport layer

Layer 7 aka application layer

Management by ambient

kubectl label namespace default istio.io/dataplane-mode=ambient

Policies

apiVersion: security.istio.io/v1beta1
kind: AuthorizationPolicy
metadata:
	name: allow-nothing
    namespace: default
spec: {}

Zero trust architecture

L7 authorization policies

 

wayPointProxy 

L7 authorization policies

 

wayPointProxy 

Ambient mesh uses HTTP CONNECT over mTLS to implement its secure tunnels and insert waypoint proxies in the path, a pattern we call HBONE (HTTP-Based Overlay Network Environment).

Ztunnel

Ztunnel

Client

web-api

Istiod

mTLS

wayPP

mTLS

apiVersion: gateway.networking.k8s.io/v1aplha2
kind: Gateway
metadata:
	name: web-api
    namespace: default
    annotations:
    	istio.io/service-account: web-api
spec: 
	gatewayClassName: istio-mesh
    
    
    
// kubectl get pods -l ambient-type=waypoint

wayPointProxy 

Ztunnel

Ztunnel

Client

web-api

Istiod

mTLS

wayPP

mTLS

wayPointProxy 

Authorisation for L7 layer  (exemple: allow GET and not DELETE verb)

Fault Injection

Traffic Shifting

Security change

Ztunnel Packet Flow

Ztunnel Packet Flow

Source Ztunnel

Aka Hbone tunnel

Ztunnel Packet Flow

Destination Ztunnel

Packet Flow

Ztunnels + Waypoint Proxy

Packet Flow

Ztunnels + Outside of Mesh

Egress

Ingress

Q/A

With the persistent Hbone connection how does the load balancing work ? Are there multiple connections in endpoints or the traffic just always flow to a single destination service ?


So the currently works is that there would be a new connection for each workload Tuple. Right now i think it just all they all share a single Hbone connection. I imagine it wouldn't be that difficult to do some sort of load balancing for Ztunnel to Ztunnel. We are looking at the ability to scale the WaypointProxies in which case there would be some sort of L4 LB

"Justin Pettit"

SandBox testing

Env: Mac M1Pro 16go & K3s cluster (2 nodes : 1 master , 1 agent)

Installation

https://istio.io/latest/docs/setup/getting-started/

curl -L https://istio.io/downloadIstio | ISTIO_VERSION=1.18.0-alpha.0 TARGET_ARCH=x86_64 sh -

export PATH="$PATH:/istio-1.18.0-alpha.0/bin"

istioctl install --set profile=ambient

This will install the Istio 1.18.0 ambient profile with ["Istio core" "Istiod" "CNI" "Ztunnel" "Ingress gateways"] components into the cluster

All components are ready !

Deploy The book App

kubectl apply -f samples/bookinfo/platform/kube/bookinfo.yaml

# The curl clients 
kubectl apply -f samples/sleep/sleep.yaml
kubectl apply -f samples/sleep/notsleep.yaml

#Access to the app from outside the cluster
kubectl apply -f samples/bookinfo/networking/bookinfo-gateway.yaml

Testing the deployment:

Deploy The book App

kubectl label namespace default istio.io/dataplane-mode=ambient

Add the application to ambient Mesh

The best part is that there was no need to restart or redeploy anything

Watch the traffic 

kubectl apply -f https://raw.githubusercontent.com/istio/istio/master/samples/addons/prometheus.yaml

kubectl apply -f https://raw.githubusercontent.com/istio/istio/master/samples/addons/kiali.yaml

Install Prometheus and Kiali

Troubleshooting

Istio CNI is configured as chained plugin, but cannot find existing CNI network config: no networks found in /host/etc/cni/net.d

Problem 1

Check if the CNI configuration files exist in the expected directory /etc/cni/net.d. If they do not exist, make sure that the installation script has permissions to write to that directory.

If the CNI configuration files do exist in the expected directory, but the Istio CNI plugin is still failing to find them, check the Istio CNI plugin configuration to make sure it is configured correctly. The configuration files for the Istio CNI plugin should be located in the /etc/cni/net.d/istio-cni.conflist file.

If it doesn't exist create it.

Solution :

Troubleshooting

Problem 1File: istio-cni.conflist

{
    "cniVersion": "0.3.0",
    "name": "istio-cni",
    "plugins": [
        {
            "name": "istio-cni",
            "type": "istio-cni",
            "hairpinMode": true,
            "ipam": {
                "type": "host-local",
                "subnet": "10.10.0.0/16",
                "routes": [
                    { "dst": "0.0.0.0/0" }
                ]
            }
        },
        {
            "type": "flannel",
            "delegate": {
                "hairpinMode": true,
                "isDefaultGateway": true
            }
        },
        {
            "type": "portmap",
            "capabilities": {
                "portMappings": true
            }
        }
    ]
}

sudo systemctl stop k3s & vi /etc/cni/net.d/istio-cni.conflist
sudo systemctl start k3s

Do the same thing to all your agents

Troubleshooting

Problem 2

kubectl exec deploy/sleep -- curl -s http://istio-ingressgateway.istio-system/productpage

upstream connect error or disconnect/reset before headers. retried and the latest reset reason: connection failure, transport failure reason: delayed connect error: 22

Troubleshooting

Problem 2

upstream connect error or disconnect/reset before headers. retried and the latest reset reason: connection failure, transport failure reason: delayed connect error: 22

Solution:

istioctl proxy-config route istio-ingress-[YOU POD ID] -n istio-system

First verify that the Istio configuration is correct, the svc and pods are running and that traffic is being correctly routed.

You can use the command:

kubectl logs -n istio-system istio-ingressgateway-[YOUR POD ID]

And check the logs:

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