I have RabbitMQ service running in an AKS (Azure Kubernetes Service) cluster as type LoadBalancer. While I am able to use the pod and service IP by providing http://<IP address>:<port number>/ to access RabbitMQ management page on VMs peered to the cluster's VNET, I am not able to access the page using http://<servicename>.<namespace>.svc.cluster.local URL with or without the ports appended. What could be done for this to work?
I discovered that the svc.cluster.local URLs resolve to the cluster IP and not external IP of the Load Balancer service. I figured this out after running a nslookup <URL> from one of the pods in the namespace. I am now evaluating the possibility of setting a static IP for the external IP or use the Azure application gateway.
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I have installed my kubernetes cluster on Jelastic. Now, I tried to define a service of LoadBalancer type and would like it to be provided with an external IP. The external IP is currently marked as pending. What should I do to make it non-pending? Do I have to provide the worker nodes with an external IPv4?
In my current setup, my worker nodes have no IPv4 because I put an nginx load-balancer in front of the cluster:
The IPv4 is set on the nginx node. Is that a problem? If I want to access my loadbalancer service inside of my kubernetes cluster, what should I do?
For LoadBalancer service type to work, the cloud provider must implemenet the relevant APIs to get it to work.
With regard to Jelastic, as per their docs, they don't support it https://docs.jelastic.com/kubernetes-exposing-services/:
Jelastic PaaS does not support the LocaBalancer service type currently.
In Jelastic Public IP addresses have to be attached to worker nodes.
Every worker node has ingress controller instance running (based oт nginx/haproxy/traefik) with http/https listeners that can forward traffic to the required service.
You have just to bind your domain as CNAME to Environment FQDN and every your worker node can accept requests in RR-DNS mode.
Does this scenario works for you or you have a specific requirement to use external load balancer?
By default, when Public IPs are not attached to worker instances the traffic is going through the Shared Load Balancer.
P.S. If you install Certification Manager Addon to your K8s cluster - you can also issue free Let's Encrypt certificates.
I have used kubectl proxy to access the kubernetes dashboard but i want to make it accessible now to my co-worker.
Do i need a load balancer or there is a more efficient way ?
You should take a look at the Ingress resource, you can use those to expose multiple Services under the same IP address.
Another option are Services of type NodePort. You can use those to expose a Service on a port of each Node in the cluster.
I have a requirement that the server that is running inside one of my container in a k8s cluster should be able to reach a server that is running in some other machine (currently its in AWS).Now the problem is that both the server (in AWS & Kubernetes Cluster) should be able to reach each other.
My server in AWS is not able to ping my Server running in Kubernetes Cluster.
Is that possible? Can we do it ?
Yes you can use ingress-nginx to create publicly reachable services ingress-nginx
If you want to do it manually you can setup load balancers that map to specific ip ranges for your nodes. This is for ssh traffic.
yes you can use ingress kubernetes object it will create publicly reachable services.
Mainly if you are using aws or digital-ocean and you will use ingress it will make load balancer (ELB or ALB) and make public service and you can access server running inside kubernetes
By manually also you can do it just simply use kubernetes service and expose it using load balancer and NODE port
https://kubernetes.io/docs/concepts/services-networking/service/
I've deployed a hello-world application on my Kubernetes cluster. When I access the app via <cluster ip>:<port> in my browser I get the following webpage: hello-kuleuven app webpage.
I understand that from outside the cluster you have to access the app via the cluster IP and the port specified in the deployment file (which in my case is 30001). From inside the cluster you have to contact the master node with its local IP and another port number, in my case 10.111.152.164:8080.
My question is about the last line of the webpage:
Kubernetes listening in 443 available at tcp://10.96.0.1:443
Since, the service is already accessible from inside and outside the cluster by other ports and IP's, I'm not sure what this does.
The IP 10.96.0.1 is a cluster IP of kube-dns service. You can see it using
kubectl get svc -n kube-apiserver
Kubernetes DNS schedules a DNS Pod and Service on the cluster, and configures the kubelets to tell individual containers to use the DNS Service’s IP to resolve DNS names.
So every pod you deploy uses kube-dns service (ClusterIP 10.96.0.1) to resolve the dns names.
Read more about kube dns at kubernetes official document here
I created a kubernetes service something like this on my 4 node cluster:
kubectl expose deployment distcc-deploy --name=distccsvc --port=8080
--target-port=3632 --type=LoadBalancer
The problem is how do I expose this service to an external ip. Without an external ip you can not ping or reach this service endpoint from outside network.
I am not sure if i need to change the kubedns or put some kind of changes.
Ideally I would like the service to be exposed on the host ip.
Like http://localhost:32876
hypothetically let's say
i have a 4 node vm on which i am running let's say nginx service. i expose it as a lodabalancer service. how can i access the nginx using this service from the vm ?
let's say the service name is nginxsvc is there a way i can do http://:8080. how will i get this here for my 4 node vm ?
LoadBalancer does different things depending on where you deployed kubernetes. If you deployed on AWS (using kops or some other tool) it'll create an elastic load balancer to expose the service. If you deployed on GCP it'll do something similar - Google terminology escapes me at the moment. These are separate VMs in the cloud routing traffic to your service. If you're playing around in minikube LoadBalancer doesn't really do anything, it does a node port with the assumption that the user understands minikube isn't capable of providing a true load balancer.
LoadBalancer is supposed to expose your service via a brand new IP address. So this is what happens on the cloud providers, they requisition VMs with a separate public IP address (GCP gives a static address and AWS a DNS). NodePort will expose as a port on kubernetes node running the pod. This isn't a workable solution for a general deployment but works ok while developing.