This guide describes AppSwitch’s integration with Kubernetes and Istio.
AppSwitch can serve as the network backend for Kubernetes. In a Kubernetes cluster, AppSwitch can be deployed with the DaemonSet spec like below. The only required customization before creating the DaemonSet is
args: a comma-separated list of one or more of existing nodes in the AppSwitch cluster (Eg.,
args: ["--neighbors","<ip1>,<ip2>"]). For simplicity and availability, all nodes in the Kubernetes cluster shown by
kubectl get nodes can be added.
--- apiVersion: apps/v1 kind: DaemonSet metadata: name: kube-appswitch namespace: kube-system labels: k8s-app: appswitch spec: selector: matchLabels: name: kube-appswitch template: metadata: labels: name: kube-appswitch spec: hostNetwork: true hostPID: true containers: - name: appswitch-daemon image: appswitch/ax args: ["--neighbors","<ip1>,<ip2>"] resources: requests: cpu: "200m" memory: "200Mi" limits: cpu: "200m" memory: "200Mi" securityContext: privileged: true volumeMounts: - name: bin mountPath: /usr/bin - name: sock mountPath: /var/run/appswitch volumes: - name: bin hostPath: path: /usr/bin - name: sock hostPath: path: /var/run/appswitch
Then the DaemonSet itself can be created as follows.
$ kubectl create -f kube-daemonset.yaml
At this point, the Kubernetes cluster is primed to run applications based on AppSwitch. The pod spec needs a few small changes to use AppSwitch. This sample nginx pod spec illustrates those changes:
apiVersion: v1 kind: Pod metadata: name: nginx spec: containers: - name: nginx image: nginx command: ['/usr/bin/ax','run','--ip','22.214.171.124',nginx, '-g', 'daemon off;'] ports: - containerPort: 80 volumeMounts: - name: bin mountPath: /usr/bin/ax - name: run mountPath: /var/run/appswitch volumes: - name: bin hostPath: path: /usr/bin/ax - name: run hostPath: path: /var/run/appswitch
This creates an nginx pod enabled to run with AppSwitch. The changes from a typical nginx pod spec are:
commandis prefixed with
axand its parameters
/var/run/appswitchhost paths are mounted into the container
The application can be deployed to the cluster the normal way.
$ kubectl create -f nginx.yaml
Once deployed, you can connect to this nginx pod from any node in the cluster as follows.
$ ax run --ip 126.96.36.199 curl -I 188.8.131.52 HTTP/1.1 200 OK Server: nginx/1.12.2 Date: Tue, 20 Mar 2018 21:21:22 GMT Content-Type: text/html Content-Length: 3700 Last-Modified: Wed, 18 Oct 2017 08:08:18 GMT Connection: keep-alive ETag: "59e70bf2-e74" X-Backend-Server: host2 Accept-Ranges: bytes
AppSwitch is integrated with Istio to serve as a highly efficient dataplane through the AppSwitch Istio agent that consumes Pilot (XDS) API and conveys traffic management policies to AppSwitch.