does daemonset need RBAC in kubernetes? - kubernetes

When I deploy a deamonset in kubernetes(1.7+), i.e, nginx ingress as daemonset, do I need to set some rbac rule ??? I know I need to set some rbac rule if I use deployment.

To deploy ingress, you need to enable some RBAC rules. In the nginx controller repository you can find the RBAC rules: https://github.com/kubernetes/ingress/blob/master/examples/rbac/nginx/nginx-ingress-controller-rbac.yml

To create daemonset you don't need to create RBAC rules for it. You might need RBAC for what is running in your Pod, be it via Deployment, Daemonset or whatever. It is the software you're running inside that might want to interact with kubernetes API, like it is in case of Ingress Controller. So, it is in fact irrelevant how you make the Pod happen, the RBAC (Cluster)Role, bindings etc. It is what soft you deploy, that defines what access rules it needs.

I was able to enable RBAC using helm (--set rbac.create=true) and this error is not seen anymore, and the nginx ingress controller is working as expected!
helm install --name my-release stable/nginx-ingress --set rbac.create=true

Related

Installing telepresence with a pod security policy

I'm trying to install telepresence into a EKS cluster that has PodSecurityPolicy's. I've gotten the traffic manager installed by running helm on the traffic manager chart:
helm install traffic-manager -n ambassador datawire/telepresence --create-namespace
After that I modify the traffic-manager-ambassador clusterRole to use one of the cluster PodSecurityPolicy's. Installation of the traffic manager eventually succeeds after I do this. However the installation of the uninstall-agent job fails:
Error creating: pods "uninstall-agents-" is forbidden: PodSecurityPolicy: unable to admit pod: []
My question is - what role or clusterRole do I have to modify to allow helm to uninstall telepresence? Or how do I figure out what service account is being used to try and install the pod so I can give it access to a pod security policy?
I made some fixes at https://github.com/ddl-pjohnson/telepresence/pull/1/files to make it easier to add additional rules and to run the helm hook as the correct user.

How to install istio mutating webhook and istiod first ahead of other pods in Helm?

I am trying to use Helm 3 to install Kubeflow 1.3 with Istio 1.9 on Kubernetes 1.16. Kubeflow does not provide official Helm chart so I figured it out by myself.
But Helm does not guarantee order. Pods of other deployments and statefulsets could be up before Istio mutating webhook and istiod are up. For example, if A pod is up earlier without istio-proxy, B pod is up later with a istio-proxy, they cannot communicate with each other.
Are there any simple best practices so I can work this out as expected each time I deploy? That is say, make sure my installation with Helm is atomic?
Thank you in advance.
UPDATE:
I tried for three ways:
mark resources as pre-install, post-install, etc.
using subcharts
decouple one chart into several charts
And I adopted the third. The issue of the first is that helm hook is designed for Job, a resource could be marked as helm hook but it would not be deleted when using helm uninstall since a resource cannot hold two helm hooks at the same time(key conflict in annotations). The issue of the second is that helm installs subcharts and charts at the same time, helm call hooks of subcharts and charts at the same time as well.
Helm does not guarantee order.
Not completely. Helm collects all of the resources in a given Chart and it's dependencies, groups them by resource type, and then installs them in the following order:
Namespace
NetworkPolicy
ResourceQuota
LimitRange
PodSecurityPolicy
PodDisruptionBudget
ServiceAccount
Secret
SecretList
ConfigMap
StorageClass
PersistentVolume
PersistentVolumeClaim
CustomResourceDefinition
ClusterRole
ClusterRoleList
ClusterRoleBinding
ClusterRoleBindingList
Role
RoleList
RoleBinding
RoleBindingList
Service
DaemonSet
Pod
ReplicationController
ReplicaSet
Deployment
HorizontalPodAutoscaler
StatefulSet
Job
CronJob
Ingress
APIService
Additionally:
That is say, make sure my installation with Helm is atomic
you should to know that:
Helm does not wait until all of the resources are running before it exits.
You generally have no control over the order if you are using Helm. You can try to use Init Containers to validate your pods to check if they have all dependencies before they run. You can read more about it here. Another workaround will be to install a health check to make sure everything is okay. If not, it will restart until it is successful.
See also:
this article about checking your helm deployments.
question Helm Subchart order of execution in an umbrella chart with good explanation
this question
related topic on github

Add TLS ingress to Kubernetes deployment

I have a working kubernetes cluster where ingress and letsencrypt is working just fine when I use helm charts. I have a deployment not included in a chart that I want to expose using ingress with TLS. How can I do this with kubectl commands?
EDIT: I can manually create an ingress but I don't have a secret so HTTPS won't work. So my question is probably "How to create a secret with letsencrypt to use on a new ingress for an existing deployment"
Google provides a way to do this for their own managed certificates. The documentation for it is at https://cloud.google.com/kubernetes-engine/docs/how-to/managed-certs.

what is an ingress controller and how do I create it?

Good morning guys, so I took down a staging environment for a product on GCP and ran the deployment scripts again, the backend and frontend service have been setup. I have an ingress resource and a load balancer up, however, the service is not running. A look at the production app revealed there was something like an nginx-ingress-controller. I really don't understand all these and how it was created. Can someone help me understand because I have not seen anything online that makes it clear for me. Am I missing something?
loadBalancer: https://gist.github.com/davidshare/5a571e56febe7dacd580282b373f3095
Ingress Resource: https://gist.github.com/davidshare/d0f53912bc7da8310ec3d64f1c8a44f1
Ingress allows access to your Kubernetes services from outside the Kubernetes cluster. There are different kubernetes aka K8 resources alternatively you can use like (Node Port / Loadbalancer) which you can use to expose.
Ingress is independent resource to your service , you can specify routing rules declaratively, so each url with some context can be mapped to different services.
This makes it decoupled and isolated from the services you want to expose.
So to work ingress it needs an Ingress Controller for your cluster.
Like deployment resource in K8, ingress can be created simply by
kubectl create -f ingress.yaml
First, you have to implement Ingress Controller in order to apply Ingress resource, as described in #Shubhu answer. Ingress controller, as an edge router, applies specific logical structure with aim to route external traffic to your Kubernetes cluster underlying services via basic pattern routing rules defined in Ingress resource.
If you select Nginx Ingress Controller then it might be useful to proceed with installation guide approaching some specific prerequisites based on cloud provider environment. In order to simplify Nginx Ingress controller installation procedure it is also possible to use Helm package manager and install appropriate stable/nginx-ingress Helm chart.

Traefik load balancer via helm chart does not route any traffic

I was trying to set up a traefik load balancer as an alternative LB for nginx-ingress. I used the helm chart from https://github.com/helm/charts/tree/master/stable/traefik and installed on my GKE cluster with rbac enabled since I use Kubernetes v1.12:
helm install --name traefik-lb --namespace kube-system --set rbac.enabled=true stable/traefik
My test application's ingress.yaml points to the new ingress class now:
kubernetes.io/ingress.class: "traefik"
What I've seen in the logs is that Traefik reloads its config all the time. I would also like to know if Traefik definitely needs a TLS cert to "just" route traffic.
What I've seen in the logs is that traefik reloads its config all the time.
It should reload every time you change the Ingress resources associated with it (The Traefik ingress controller). If it reloads all the time without any change to your cluster, there may be an issue with Traefik itself or the way your cluster is set up.
I would also like to know if traefik definitely needs a TLS cert to "just" route traffic.
No, it doesn't. This basic example from the documentation shows that
you don't need TLS if you don't want to set it up.