I deleted my cluster-admin role via kubectl using:
kubectl delete clusterrole cluster-admin
Not sure what I expected, but now I don't have access to the cluster from my account. Any attempt to get or change resources using kubectl returns a 403, Forbidden.
Is there anything I can do to revert this change without blowing away the cluster and creating a new one? I have a managed cluster on Digital Ocean.
Not sure what I expected, but now I don't have access to the cluster from my account.
If none of the kubectl commands actually work, unfortunately you will not be able to create a new cluster role. The problem is that you won't be able to do anything without an admin role. You can try creating the cluster-admin role directly through the API (not using kubectl), but if that doesn't help you have to recreate the cluster.
Try applying this YAML to creaste the new Cluster role
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRole
metadata:
annotations:
rbac.authorization.kubernetes.io/autoupdate: "true"
labels:
kubernetes.io/bootstrapping: rbac-defaults
name: cluster-admin
rules:
- apiGroups:
- '*'
resources:
- '*'
verbs:
- '*'
- nonResourceURLs:
- '*'
verbs:
- '*'
apply the YAML file changes
kubectl apply -f <filename>.yaml
Related
We are enabling Google Cloud Groups RBAC in our existing GKE clusters.
For that, we first created all the groups in Workspace, and also the required "gke-security-groups#ourdomain.com" according to documentation.
Those groups are created in Workspace with an integration with Active Directory for Single Sign On.
All groups are members of "gke-security-groups#ourdomain" as stated by documentation. And all groups can View members.
The cluster was updated to enabled the flag for Google Cloud Groups RBAC and we specify the value to be "gke-security-groups#ourdomain.com".
We then Added one of the groups (let's called it group_a#ourdomain.com) to IAM and assigned a custom role which only gives access to:
"container.apiServices.get",
"container.apiServices.list",
"container.clusters.getCredentials",
"container.clusters.get",
"container.clusters.list",
This is just the minimum for the user to be able to log into the Kubernetes cluster and from there being able to apply Kubernetes RBACs.
In Kubernetes, we applied a Role, which provides list of pods in a specific namespace, and a role binding that specifies the group we just added to IAM.
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: test-role
namespace: custom-namespace
rules:
- apiGroups: [""]
resources: ["pods"]
verbs: ["get", "list", "watch"]
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: test-rolebinding
namespace: custom-namespace
roleRef:
kind: Role
name: test-role
apiGroup: rbac.authorization.k8s.io
subjects:
- kind: Group
name: group_a#ourdomain.com
Everything looks good until now. But when trying to list the pods of this namespace with the user that belongs to the group "group_a#ourdomain.com", we get:
Error from server (Forbidden): pods is forbidden: User
"my-user#ourdomain.com" cannot list resource "pods" in API group ""
in the namespace "custom-namespace": requires one of ["container.pods.list"]
permission(s).
Of course if I give container.pods.list to the group_a#ourdomain assigned role, I can list pods, but it opens for all namespaces, as this permission in GCloud is global.
What am I missing here?
Not sure if this is relevant, but our organisation in gcloud is called for example "my-company.io", while the groups for SSO are named "...#groups.my-company.io", and the gke-security-groups group was also created with the "groups.my-company.io" domain.
Also, if instead of a Group in the RoleBinding, I specify the user directly, it works.
It turned out to be an issue about case-sensitive strings and nothing related with the actual rules defined in the RBACs, which were working as expected.
The names of the groups were created in Azure AD with a camel case model. These group names where then showed in Google Workspace all lowercase.
Example in Azure AD:
thisIsOneGroup#groups.mycompany.com
Example configured in the RBACs as shown in Google Workspace:
thisisonegroup#groups.mycompany.com
We copied the names from the Google Workspace UI all lowercase and we put them in the bindings and that caused the issue. Kubernetes GKE is case sensitive and it didn't match the name configured in the binding with the email configured in Google Workspace.
After changing the RBAC bindings to have the same format, everything worked as expected.
Looks like you are trying to grant access to deployments in the extensions and apps API groups. That requires the user to specify the extensions and apps api group in your role rules:
rules:
- apiGroups:
- ""
resources:
- pods
verbs:
- '*'
- apiGroups:
- extensions
- apps
resources:
- deployments
- replicasets
verbs:
- '*'
I can recommend you to recreate role and role bindings too. You can visit the following thread as a reference too RBAC issue : Error from server (Forbidden):
Edited 012622:
Can you please confirm that you provided the credentials or configuration file (manifest, YAML)? As you may know, this information is provided by Kubernetes and the default service account. You can verify it by running:
$ kubectl auth can-i get pods
Let me tell you that the account type you need to use for your accounts is “service account”. To create a new service account with a wider set of permissions, the following is a YAML example:
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
namespace: default
name: pod-read-role
rules:
- apiGroups: [""] # "" indicates the core API group
resources: ["pods"]
verbs: ["get", "watch", "list"]
---
apiVersion: v1
kind: ServiceAccount
metadata:
name: pod-read-sa
---
kind: RoleBinding
apiVersion: rbac.authorization.k8s.io/v1
metadata:
name: pod-read-rolebinding
namespace: default
subjects:
- kind: ServiceAccount
name: pod-read-sa
apiGroup: ""
roleRef:
kind: Role
name: pod-read-role
apiGroup: ""
Please use the following thread as a reference.
I am trying to establish the namespace "sandbox" in Kubernetes and have been using it for several days for several days without issue. Today I got the below error.
I have checked to make sure that I have all of the requisite configmaps in place.
Is there a log or something where I can find what this is referring to?
panic: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable
I did find this (MountVolume.SetUp failed for volume "kube-api-access-fcz9j" : object "default"/"kube-root-ca.crt" not registered) thread and have applied the below patch to my service account, but I am still getting the same error.
automountServiceAccountToken: false
UPDATE:
In answer to #p10l I am working in a bare-metal cluster version 1.23.0. No terraform.
I am getting closer, but still not there.
This appears to be another RBAC problem, but the error does not make sense to me.
I have a user "dma." I am running workflows in the "sandbox" namespace using the context dma#kubernetes
The error now is
Create request failed: workflows.argoproj.io is forbidden: User "dma" cannot create resource "workflows" in API group "argoproj.io" in the namespace "sandbox"
but that user indeed appears to have the correct permissions.
This is the output of
kubectl get role dma -n sandbox -o yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
annotations:
kubectl.kubernetes.io/last-applied-configuration: |
{"apiVersion":"rbac.authorization.k8s.io/v1","kind":"Role","metadata":{"annotations":{},"name":"dma","namespace":"sandbox"},"rules":[{"apiGroups":["","apps","autoscaling","batch","extensions","policy","rbac.authorization.k8s.io","argoproj.io"],"resources":["pods","configmaps","deployments","events","pods","persistentvolumes","persistentvolumeclaims","services","workflows"],"verbs":["get","list","watch","create","update","patch","delete"]}]}
creationTimestamp: "2021-12-21T19:41:38Z"
name: dma
namespace: sandbox
resourceVersion: "1055045"
uid: 94191881-895d-4457-9764-5db9b54cdb3f
rules:
- apiGroups:
- ""
- apps
- autoscaling
- batch
- extensions
- policy
- rbac.authorization.k8s.io
- argoproj.io
- workflows.argoproj.io
resources:
- pods
- configmaps
- deployments
- events
- pods
- persistentvolumes
- persistentvolumeclaims
- services
- workflows
verbs:
- get
- list
- watch
- create
- update
- patch
- delete
This is the output of kubectl get rolebinding -n sandbox dma-sandbox-rolebinding -o yaml
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
annotations:
kubectl.kubernetes.io/last-applied-configuration: |
{"apiVersion":"rbac.authorization.k8s.io/v1","kind":"RoleBinding","metadata":{"annotations":{},"name":"dma-sandbox-rolebinding","namespace":"sandbox"},"roleRef":{"apiGroup":"rbac.authorization.k8s.io","kind":"Role","name":"dma"},"subjects":[{"kind":"ServiceAccount","name":"dma","namespace":"sandbox"}]}
creationTimestamp: "2021-12-21T19:56:06Z"
name: dma-sandbox-rolebinding
namespace: sandbox
resourceVersion: "1050593"
uid: d4d53855-b5fc-4f29-8dbd-17f682cc91dd
roleRef:
apiGroup: rbac.authorization.k8s.io
kind: Role
name: dma
subjects:
- kind: ServiceAccount
name: dma
namespace: sandbox
The issue you are describing is a reoccuring one, described here and here where your cluster lacks KUBECONFIG environment variable.
First, run echo $KUBECONFIG on all your nodes to see if it's empty.
If it is, look for the config file in your cluster, then copy it to all the nodes, then export this variable by running export KUBECONFIG=/path/to/config. This file can be usually found at ~/.kube/config/ or /etc/kubernetes/admin.conf` on master nodes.
Let me know, if this solution worked in your case.
I have 2 teams:
devs: they create a new Kubernetes namespace each time they deploy a branch/tag of their app
ops: they manage access control to the cluster with (cluster)roles and (cluster)rolebindings
The problem is that 'devs' cannot kubectl their namespaces until 'ops' have created RBAC resources. And 'devs' cannot create RBAC resources themselves as they don't have the list of subjects to put in the rolebinding resource (sharing the list is not an option).
I have read the official documentation about Admission webhooks but what I understood is that they only act on the resource that triggered the webhook.
Is there a native and/or simple way in Kubernetes to apply resources whenever a new namespace is created?
I've come up with a solution by writing a custom controller.
With the following custom resource deployed, the controller injects the role and rolebinding in namespaces matching dev-.* and fix-.*:
kind: NamespaceResourcesInjector
apiVersion: blakelead.com/v1alpha1
metadata:
name: nri-test
spec:
namespaces:
- dev-.*
- fix-.*
resources:
- |
apiVersion: rbac.authorization.k8s.io/v1
kind: Role
metadata:
name: dev-role
rules:
- apiGroups: [""]
resources: ["pods","pods/portforward", "services", "deployments", "ingresses"]
verbs: ["list", "get"]
- apiGroups: [""]
resources: ["pods/portforward"]
verbs: ["create"]
- apiGroups: [""]
resources: ["namespaces"]
verbs: ["list", "get"]
- |
apiVersion: rbac.authorization.k8s.io/v1
kind: RoleBinding
metadata:
name: dev-rolebinding
subjects:
- kind: User
name: dev
roleRef:
kind: Role
name: dev-role
apiGroup: rbac.authorization.k8s.io
The controller is still in early stages of development but I'm using it successfully in more and more clusters.
Here it is for those interested: https://github.com/blakelead/nsinjector
Yes, there is a native way but not an out of the box feature.
You can do what you have described by using/creating an operator. Essentially extending Kubernetes APIs for your need.
As operator is just an open pattern which can implement things in many ways, in the scenario you gave one way the control flow could look like could be:
Operator with privileges to create RBAC is deployed and subscribed to changes to a k8s namespace object kind
Devs create namespace containing an agreed label
Operator is notified about changes to the cluster
Operator checks namespace validation (this can also be done by a separate admission webhook)
Operator creates RBAC in the newly created namespace
If RBACs are cluster wide, same operator can do the RBAC cleanup once namespace is deleted
It's kind of related to how the user is authenticated to the cluster and how they get a kubeconfig file.You can put a group in the client certificate or the bearer token that kubectl uses from the kubeconfig. Ahead of time you can define a clusterrole having a clusterrolebinding to that group which gives them permission to certain verbs on certain resources(for example ability to create namespace)
Additionally you can use an admission webhook to validate if the user is supposed to be part of that group or not.
I want to allow a user to do things in the Kubernetes cluster for EKS for example: apply deployment, create secrets, create volumes etc.
I'm not sure which role to use for that. I don't want to allow users:
to create clusters, delete clusters, list cluster only perform the Kubernetes operations within the cluster.
As far as I know the permissions to the cluster are performed with Heptio authenticator. I believe I am missing something here but can't figure out what.
This link is the right one to add an AWS IAM user or AWS Role to a given K8S Role.
Let's say that you wanted to create a new K8S Role to only have read permission, called pod-reader
kind: Role
apiVersion: rbac.authorization.k8s.io/v1
metadata:
namespace: default
name: pod-reader
rules:
- apiGroups: [""] # "" indicates the core API group
resources: ["pods"]
verbs: ["get", "watch", "list"]
After creating the role, you need to give the permission to your IAM user to assume that role. This is easily doable doing:
apiVersion: v1
kind: ConfigMap
metadata:
name: aws-auth
namespace: kube-system
data:
mapUsers: |
- userarn: arn:aws:iam::270870090353:user/franziska_adler
username: iam_user_name
groups:
- pod-reader
More information about K8S RBAC Authorization here
Looks like you have to manually add the users in the config map under the 'mapUsers' item and then run kubectl apply config-map.yml according the aws documentation in section 3. "Add your IAM users, roles, or AWS accounts to the configMap."
https://docs.aws.amazon.com/eks/latest/userguide/add-user-role.html
Forbidden!Configured service account doesn't have access. Service account may have been revoked. User "system:serviceaccount:default:default" cannot get services in the namespace "mycomp-services-process"
For the above issue I have created "mycomp-service-process" namespace and checked the issue.
But it shows again message like this:
Message: Forbidden!Configured service account doesn't have access. Service account may have been revoked. User "system:serviceaccount:mycomp-services-process:default" cannot get services in the namespace "mycomp-services-process"
Creating a namespace won't, of course, solve the issue, as that is not the problem at all.
In the first error the issue is that serviceaccount default in default namespace can not get services because it does not have access to list/get services. So what you need to do is assign a role to that user using clusterrolebinding.
Following the set of minimum privileges, you can first create a role which has access to list services:
kind: ClusterRole
apiVersion: rbac.authorization.k8s.io/v1
metadata:
namespace: default
name: service-reader
rules:
- apiGroups: [""] # "" indicates the core API group
resources: ["services"]
verbs: ["get", "watch", "list"]
What above snippet does is create a clusterrole which can list, get and watch services. (You will have to create a yaml file and apply above specs)
Now we can use this clusterrole to create a clusterrolebinding:
kubectl create clusterrolebinding service-reader-pod \
--clusterrole=service-reader \
--serviceaccount=default:default
In above command the service-reader-pod is name of clusterrolebinding and it is assigning the service-reader clusterrole to default serviceaccount in default namespace. Similar steps can be followed for the second error you are facing.
In this case I created clusterrole and clusterrolebinding but you might want to create a role and rolebinding instead. You can check the documentation in detail here
This is only for non prod clusters
You should bind service account system:serviceaccount:default:default (which is the default account bound to Pod) with role cluster-admin, just create a yaml (named like fabric8-rbac.yaml) with following contents:
# NOTE: The service account `default:default` already exists in k8s cluster.
# You can create a new account following like this:
#---
#apiVersion: v1
#kind: ServiceAccount
#metadata:
# name: <new-account-name>
# namespace: <namespace>
---
apiVersion: rbac.authorization.k8s.io/v1
kind: ClusterRoleBinding
metadata:
name: fabric8-rbac
subjects:
- kind: ServiceAccount
# Reference to upper's `metadata.name`
name: default
# Reference to upper's `metadata.namespace`
namespace: default
roleRef:
kind: ClusterRole
name: cluster-admin
apiGroup: rbac.authorization.k8s.io
Then, apply it by running kubectl apply -f fabric8-rbac.yaml.
If you want unbind them, just run kubectl delete -f fabric8-rbac.yaml.
Just to add.
This can also occur when you are redeploying an existing application to the wrong Kubernetes cluster that are similar.
Ensure you check to be sure that the Kubernetes cluster you're deploying to is the correct cluster.