使用Helm从0到K8S再到叶子节点

First, we need a number of Kubernetes clusters to be setup already. In this case we'll create a few in Digital Ocean using the doctl tool but you could use any K8S solution available:

brew install doctl
doctl kubernetes cluster create nats-k8s-sfo2 --count 3 --region sfo2
doctl kubernetes cluster create nats-k8s-ams3 --count 3 --region ams3

Next, get your NGS credentials with leafnodes enabled. For this follow these instructions and choose the Developer plan which is free and will allow you to create leafnode connections for a couple of clusters. Once you got the credentials, upload them as a secret to your K8S clusters:

for ctx in do-ams3-nats-k8s-ams3 do-sfo2-nats-k8s-sfo2; do
  kubectl --context $ctx create secret generic ngs-creds --from-file $HOME/.nkeys/creds/synadia/NGS/NGS.creds
done

Install Helm3 and add the NATS helm chart repo:

brew install helm
helm repo add nats https://nats-io.github.io/k8s/helm/charts/
helm repo update

Create the config that adds the leafnode connection to Synadia's NGS:

# nats.yaml
leafnodes:
  enabled: true
  remotes:
    - url: tls://connect.ngs.global:7422
      credentials:
        secret:
          name: ngs-creds
          key: NGS.creds
natsbox:
  enabled: true

Deploy it to your K8S regions:

for ctx in do-ams3-nats-k8s-ams3 do-sfo2-nats-k8s-sfo2; do
  helm --kube-context $ctx install nats nats/nats -f nats.yaml
done

To test the multi-region connectivity by using the nats-box container that got deployed in each cluster:

kubectl --context do-ams3-nats-k8s-ams3  exec -it nats-box -- nats sub -s nats hello
Listening on [hello]

while true; do
  kubectl --context do-sfo2-nats-k8s-sfo2  exec -it nats-box -- nats pub -s nats hello 'Hello World!'
done

Results from the subscribe session:

[#1] Received on [hello]: 'Hello World!'
[#2] Received on [hello]: 'Hello World!'
[#3] Received on [hello]: 'Hello World!'
[#4] Received on [hello]: 'Hello World!'
[#5] Received on [hello]: 'Hello World!'
[#6] Received on [hello]: 'Hello World!'
[#7] Received on [hello]: 'Hello World!'
[#8] Received on [hello]: 'Hello World!'
[#9] Received on [hello]: 'Hello World!'