Raven

This document introduces how to install raven and use raven to enhance edge-edge and edge-cloud network communication in an edge cluster.

Suppose you have an edge kubernetes cluster with nodes in different physical regions, and already deploy the Raven Controller Manager in this cluster, the details of Raven Controller Manager are in here.

Label nodes in different physical regions

As follows, suppose the cluster has five nodes, located in three different regions, where the node master is cloud node.

  1. $ kubectl get nodes -o wide
  3. NAME         STATUS   ROLES    AGE   VERSION   INTERNAL-IP    
  4. hhht-node1   Ready    <none>   20d   v1.16.2   10.48.115.9    
  5. hhht-node2   Ready    <none>   20d   v1.16.2   10.48.115.10
  6. master       Ready    master   20d   v1.16.2   10.48.115.8
  7. wlcb-node1   Ready    <none>   20d   v1.16.2   10.48.115.11
  8. wlcb-node2   Ready    <none>   20d   v1.16.2   10.48.115.12

We use a Gateway CR to manage nodes in different physical regions, and label nodes to indicate which Gateway these nodes are managed by.

For example, We label nodes in region cn-huhehaote with value gw-hhht, indicating that these nodes are managed by the gw-hhht gateway.

  1. $ kubectl label nodes hhht-node1 hhht-node2 raven.openyurt.io/gateway=gw-hhht
  2. hhht-node1 labeled
  3. hhht-node2 labeled

Similarly, we label node in cloud with value gw-cloud, and nodes in region cn-wulanchabu with value gw-wlcb.

  1. $ kubectl label nodes master raven.openyurt.io/gateway=gw-cloud
  2. master labeled
  1. $ kubectl label nodes wlcb-node1 wlcb-node2 raven.openyurt.io/gateway=gw-wlcb
  2. wlcb-node1 labeled
  3. wlcb-node2 labeled

install raven agent

  1. git clone https://github.com/openyurtio/raven.git
  2. cd raven
  3. make deploy

Wait for the raven agent daemon to be created successfully

  1. $ kubectl get pod -n kube-system | grep raven-agent-ds
  2. raven-agent-ds-2jw47                           1/1     Running   0          91s
  3. raven-agent-ds-bq8zc                           1/1     Running   0          91s
  4. raven-agent-ds-cj7k4                           1/1     Running   0          91s
  5. raven-agent-ds-p9fk9                           1/1     Running   0          91s
  6. raven-agent-ds-rlb9q                           1/1     Running   0          91s

How to Use

Gateways

  • create gateways
  1. $ cat <<EOF | kubectl apply -f -
  2. apiVersion: raven.openyurt.io/v1alpha1
  3. kind: Gateway
  4. metadata:
  5.   name: gw-hhht
  6. spec:
  7.   endpoints:
  8.     - nodeName: hhht-node1
  9.       underNAT: true
  10.     - nodeName: hhht-node2
  11.       underNAT: true
  13. ---
  14. apiVersion: raven.openyurt.io/v1alpha1
  15. kind: Gateway
  16. metadata:
  17.   name: gw-cloud
  18. spec:
  19.   endpoints:
  20.     - nodeName: master
  21.       underNAT: false
  23. ---
  24. apiVersion: raven.openyurt.io/v1alpha1
  25. kind: Gateway
  26. metadata:
  27.   name: gw-wlcb
  28. spec:
  29.   endpoints:
  30.     - nodeName: wlcb-node1
  31.       underNAT: true
  32.     - nodeName: wlcb-node2
  33.       underNAT: true
  35. EOF
  • Get gateways
  1. $ kubectl get gateways
  3. NAME      ACTIVEENDPOINT
  4. gw-hhht   hhht-node1
  5. gw-master master
  6. gw-wlcb   wlcb-node1

Test pod-to-pod networking

  • Create test pod
  1. $ cat <<EOF | kubectl apply -f -
  2. apiVersion: v1
  3. kind: Pod
  4. metadata:
  5.   name: fedora-1
  6. spec:
  7.   nodeName: hhht-node2
  8.   containers:
  9.     - name: fedora
  10.       image: njucjc/fedora:latest
  11.       imagePullPolicy: Always
  13. ---
  15. apiVersion: v1
  16. kind: Pod
  17. metadata:
  18.   name: fedora-2
  19. spec:
  20.   nodeName: wlcb-node2
  21.   containers:
  22.     - name: fedora
  23.       image: njucjc/fedora:latest
  24.       imagePullPolicy: Always
  27. EOF
  • Get test pod
  1. $ kubectl get pod -o wide
  2. NAME       READY   STATUS    RESTARTS   AGE     IP            NODE                  NOMINATED NODE   READINESS GATES
  3. fedora-1   1/1     Running   0          46s     10.14.10.67   hhht-node2            <none>           <none>
  4. fedora-2   1/1     Running   0          46s     10.14.2.70    wlcb-node2            <none>           <none>
  • Test networking across edge
  1. $ kubectl exec -it fedora-1 -- bash
  2. [root@fedora-1]# ping 10.14.2.70 -c 4
  3. PING 10.14.2.70 (10.14.2.70) 56(84) bytes of data.
  4. 64 bytes from 10.14.2.70: icmp_seq=1 ttl=60 time=32.2 ms
  5. 64 bytes from 10.14.2.70: icmp_seq=2 ttl=60 time=32.2 ms
  6. 64 bytes from 10.14.2.70: icmp_seq=3 ttl=60 time=32.0 ms
  7. 64 bytes from 10.14.2.70: icmp_seq=4 ttl=60 time=32.1 ms
  9. --- 10.14.2.70 ping statistics ---
  10. 4 packets transmitted, 4 received, 0% packet loss, time 3003ms
  11. rtt min/avg/max/mdev = 32.047/32.136/32.246/0.081 ms