I have a Network(Service) load balancer on GCP and a kubernetes cluster with a pod that serves traffic on 80,443. How can I create a successful health check so the load balancer marks the nodes healthy? I tried creating health check for port 80, 443 and also opened port 10250 for kubelet and tried health checking http 10250 as suggested in
Is the Google Container Engine Kubernetes Service LoadBalancer sending traffic to unresponsive hosts?
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I created a java app and I deployed into a Google Cloud Compute Engine, then I created a Load Balancer, but when I try to access to Load Balancer Frontend IP with port 443 it redirect to port 80
You can create forwarding rules that reference an IP address and port(s) on which Load balancer accepts traffic. Here are the conceps for forwarding rules 1.
IP address specification 2
To add a forwarding rule, please follow the steps here 3
I have so far configured servers inside Kubernetes containers that used HTTP or terminated HTTPS at the ingress controller. Is it possible to terminate HTTPS (or more generally TLS) traffic from outside the cluster directly on the container, and how would the configuration look in that case?
This is for an on-premises Kubernetes cluster that was set up with kubeadm (with Flannel as CNI plugin). If the Kubernetes Service would be configured with externalIPs 1.2.3.4 (where my-service.my-domain resolves to 1.2.3.4) for service access from outside the cluster at https://my-service.my-domain, say, how could the web service running inside the container bind to address 1.2.3.4 and how could the client verify a server certificate for 1.2.3.4 when the container's IP address is (FWIK) some local IP address instead? I currently don't see how this could be accomplished.
UPDATE My current understanding is that when using an Ingress HTTPS traffic would be terminated at the ingress controller (i.e. at the "edge" of the cluster) and further communication inside the cluster towards the backing container would be unencrypted. What I want is encrypted communication all the way to the container (both outside and inside the cluster).
I guess, Istio envoy proxies is what you need, with the main purpose to authenticate, authorize and encrypt service-to-service communication.
So, you need a mesh with mTLS authentication, also known as service-to-service authentication.
Visually, Service A is your Ingress service and Service B is a service for HTTP container
So, you terminate external TLS traffic on the ingress controller and it will go further inside the cluster with Istio mTLS encryption.
It's not exactly what you asked for -
terminate HTTPS traffic directly on Kubernetes container
Though it fulfill the requirement-
What I want is encrypted communication all the way to the container
I created a custom HTTPS LoadBalancer (details) and I need my Kubernetes Workload to be exposed with this LoadBalancer. For now, if I send a request to this endpoint I get the error 502.
When I choose the Expose option in the Workload Console page, there are only TCP and UDP service types available, and a TCP LoadBalancer is created automatically.
How do I expose a Kubernetes Workload with an existing LoadBalancer? Or maybe I don't even need to do it, and requests don't work because my instances are "unhealthy"? (healthcheck)
You need to create a kubernetes ingress.
First, you need to expose the deployment from k8s, for a https choose 443 port and service type can be either: LoadBalance(external ip) or ClusterIp. (you can also test that by accesing the ip or by port forwarding).
Then you need to create the ingress.
Inside yaml file when choosing the backend, set the port and ServiceName that was configured when exposing the deployment.
For example:
- path: /some-route
backend:
serviceName: your-service-name
servicePort: 443
On gcp, when ingress is created, there will be a load balancer created for that. The backends and instance groups will be automatically build too.
Then if you want to use the already created load balancer you just need to select the backend services from the lb that was created by ingress and add them there.
Also the load balancer will work only if the health checks pass. You need to use the route that will return a 200 HTTPS response for that.
I have a few ec2 instances running and I added them to a load balancer. The load balancer gives me a public DNS name but that never reaches my ec2 instances. I can reach each ec2 instance directly from the browser. All instance show that they are healthy in the control panel. My Load balancer rules take traffic on load balancer port 80 and send it to ec2 instance port 80. Each ec2 instance takes traffic on port 80 and routes to 3000 where the apps are running. There were some similar posts on their forum, but no answer.
I have set up a simple Kubernetes load balancer service in front of a Node.js container, which should be exposing port 80, but I can't get a response out of it. How can I debug how the load balancer is handling requests to port 80? Are there logs I can inspect?
I have set up a load balancer service and a replication controller as described in the Kubernetes guestbook example.
The service/load balancer spec is similar to this:
{
"kind":"Service",
"apiVersion":"v1",
"metadata":{
"name":"guestbook",
"labels":{
"app":"guestbook"
}
},
"spec":{
"ports": [
{
"port":3000,
"targetPort":"http-server"
}
],
"selector":{
"app":"guestbook"
},
"type": "LoadBalancer"
}
}
As for my hosting platform, I'm using AWS and the OS is CoreOS alpha (976.0.0). Kubectl is at version 1.1.2.
Kubernetes Info
$ ~/.local/bin/kubectl --kubeconfig=/etc/kubernetes/kube.conf get pods
NAME READY STATUS RESTARTS AGE
busybox-sleep 1/1 Running 0 18m
web-s0s5w 1/1 Running 0 12h
$ ~/.local/bin/kubectl --kubeconfig=/etc/kubernetes/kube.conf get services
NAME CLUSTER_IP EXTERNAL_IP PORT(S) SELECTOR AGE
kubernetes 10.3.0.1 <none> 443/TCP <none> 1d
web 10.3.0.171
Here is the primary debugging document for Services:
http://kubernetes.io/docs/user-guide/debugging-services/
LoadBalancer creates an external resource. What exactly that resource is depends on your Cloud Provider - some of them don't support it at all (in this case, you might want to try NodePort instead).
Both Google and Amazon support external load balancers.
Overall, when asking these questions it's extremely helpful to know if you are running on Google Container Engine, Google Compute Engine, Amazon Web Services, Digital Ocean, Vagrant, or whatever, because the answer depends on that. Showing all your configs and all your existing Kubnernetes resources (kubectl get pods, kubectl get services) along with your Dockerfiles or which images you are using will also help.
For Google (GKE or GCE), you would verify the load balancer exists:
gcloud compute forwarding-rules list
The external load balancer will map port 80 to an arbitrary Node, but then the Kubernetes proxy will map that to an ephemeral port on the correct node that actually has a Pod with that label, then it will map to the container port. So you have to figure out which step along the way isn't working. Unfortunately all those kube-proxy and iptables jumps are quite difficult to follow, so usually I would first double check all my Pods exist and have labels that match the selector of the Service. I would double check that my container is exposing the right port, I am using the right name for the port, etc. You might want to create some other Pods that just make calls to the Service (using the environment variables or KubeDNS, see the Kubernetes service documentation if you don't know what I'm referring to) and verify it's accessible internally before debugging the load balancer.
Some other good debugging steps:
Verify that your Kubernetes Service exists:
kubectl get services
kubectl get pods
Check your logs of your pod
kubectl logs <pod name>
Check that your service is created internally by printing the environment variable for it
kubectl exec <pod name> -- printenv GUESTBOOK_SERVICE_HOST
try creating a new pod and see if the service can be reached internally through GUESTBOOK_SERVICE_HOST and GUESTBOOK_SERVICE_PORT.
kubectl describe pod <pod name>
will give the instance id of the pod, you can SSH to it and run Docker and verify your container is running, attach to it, etc. If you really want to get into the IP tables debugging, try
sudo iptables-save
The target port of the LoadBalancer needs to be the port INSIDE the container. So in my case I need to set the targetPort to 3000 instead of 80, on the LoadBalancer.
Even though on the pod itself I have already mapped port 80 to 3000.
This is very counter intuitive to me, and not mentioned in all the LoadBalancer docs.