k8s | Kubernetes configuration file to boostrap | Configuration Management library

I was setting up my new Mac for my eks environment. After the installation of kubectl, aws-iam-authenticator and the kubeconfig file placement in default location. I ran the command kubectl command and got this error mentioned below in command block.

My cluster uses v1alpha1 client auth api version so basically i wanted to use the same one in my Mac as well.

I tried with latest version (1.23.0) of kubectl as well, still the same error. Whereas When i tried to do with aws-iam-authenticator (version 0.5.5) I was not able to download lower version.

Can someone help me to resolve it?

I'm following a tutorial https://docs.openfaas.com/tutorials/first-python-function/,

currently, I have the right image

I have a simple ingress configuration file-

I'm currently migrating a DAG from airflow version 1.10.10 to 2.0.0.

This DAG uses a custom python operator where, depending on the complexity of the task, it assigns resources dynamically. The problem is that the import used in v1.10.10 (airflow.contrib.kubernetes.pod import Resources) no longer works. I read that for v2.0.0 I should use kubernetes.client.models.V1ResourceRequirements, but I need to build this resource object dynamically. This might sound dumb, but I haven't been able to find the correct way to build this object.

For example, I've tried with

Whenever I am trying to run the docker images, it is exiting in immediately.

I've been trying to get over this but I'm out of ideas for now hence I'm posting the question here.

I'm experimenting with the Oracle Cloud Infrastructure (OCI) and I wanted to create a Kubernetes cluster which exposes some service.

The goal is:

• A running managed Kubernetes cluster (OKE)
• 2 nodes at least
• 1 service that's accessible for external parties

The infra looks the following:

• A VCN for the whole thing
• A private subnet on 10.0.1.0/24
• A public subnet on 10.0.0.0/24
• NAT gateway for the private subnet
• Internet gateway for the public subnet
• Service gateway
• The corresponding security lists for both subnets which I won't share right now unless somebody asks for it
• A containerengine K8S (OKE) cluster in the VCN with public Kubernetes API enabled
• A node pool for the K8S cluster with 2 availability domains and with 2 instances right now. The instances are ARM machines with 1 OCPU and 6GB RAM running Oracle-Linux-7.9-aarch64-2021.12.08-0 images.
• A namespace in the K8S cluster (call it staging for now)
• A deployment which refers to a custom NextJS application serving traffic on port 3000

And now it's the point where I want to expose the service running on port 3000.

I have 2 obvious choices:

• Create a LoadBalancer service in K8S which will spawn a classic Load Balancer in OCI, set up it's listener and set up the backendset referring to the 2 nodes in the cluster, plus it adjusts the subnet security lists to make sure traffic can flow
• Create a Network Load Balancer in OCI and create a NodePort on K8S and manually configure the NLB to the ~same settings as the classic Load Balancer

The first one works perfectly fine but I want to use this cluster with minimal costs so I decided to experiment with option 2, the NLB since it's way cheaper (zero cost).

Long story short, everything works and I can access the NextJS app on the IP of the NLB most of the time but sometimes I couldn't. I decided to look it up what's going on and turned out the NodePort that I exposed in the cluster isn't working how I'd imagine.

The service behind the NodePort is only accessible on the Node that's running the pod in K8S. Assume NodeA is running the service and NodeB is just there chilling. If I try to hit the service on NodeA, everything is fine. But when I try to do the same on NodeB, I don't get a response at all.

That's my problem and I couldn't figure out what could be the issue.

What I've tried so far:

• Switching from ARM machines to AMD ones - no change
• Created a bastion host in the public subnet to test which nodes are responding to requests. Turned out only the node responds that's running the pod.
• Created a regular LoadBalancer in K8S with the same config as the NodePort (in this case OCI will create a classic Load Balancer), that works perfectly
• Tried upgrading to Oracle 8.4 images for the K8S nodes, didn't fix it
• Ran the Node Doctor on the nodes, everything is fine
• Checked the logs of kube-proxy, kube-flannel, core-dns, no error
• Since the cluster consists of 2 nodes, I gave it a try and added one more node and the service was not accessible on the new node either
• Recreated the cluster from scratch

Edit: Some update. I've tried to use a DaemonSet instead of a regular Deployment for the pod to ensure that as a temporary solution, all nodes are running at least one instance of the pod and surprise. The node that was previously not responding to requests on that specific port, it still does not, even though a pod is running on it.

Edit2: Originally I was running the latest K8S version for the cluster (v1.21.5) and I tried downgrading to v1.20.11 and unfortunately the issue is still present.

Edit3: Checked if the NodePort is open on the node that's not responding and it is, at least kube-proxy is listening on it.

I am trying to get a volume mounted as a non-root user in one of my containers. I'm trying an approach from this SO post using an initContainer to set the correct user, but when I try to start the configuration I get an "unbound immediate PersistentVolumneClaims" error. I suspect it's because the volume is mounted in both my initContainer and container, but I'm not sure why that would be the issue: I can see the initContainer taking the claim, but I would have thought when it exited that it would release it, letting the normal container take the claim. Any ideas or alternatives to getting the directory mounted as a non-root user? I did try using securityContext/fsGroup, but that seemed to have no effect. The /var/rdf4j directory below is the one that is being mounted as root.

Configuration:

I found a source describing that the default gc used changes depending on the available resources. It seems that the jvm uses either g1gc or serial gc dependnig on hardware and os.

The serial collector is selected by default on certain hardware and operating system configurations

Can someone point out a more detailed source on what the specific criteria is and how that would apply in a dockerized/kubernetes enivronment. In other words:

Could setting resource requests of the pod in k8s to eg. 1500 mCpu make the jvm use serial gc and changing to 2 Cpu change the default gc to g1gc? Do the limits on when which gc is used change depending on jvm version (11 vs 17)?

I am trying to get my deployment to only deploy replicas to nodes that aren't running rabbitmq (this is working) and also doesn't already have the pod I am deploying (not working).

I can't seem to get this to work. For example, if I have 3 nodes (2 with label of app.kubernetes.io/part-of=rabbitmq) then all 2 replicas get deployed to the remaining node. It is like the deployments aren't taking into account their own pods it creates in determining anti-affinity. My desired state is for it to only deploy 1 pod and the other one should not get scheduled.