Instead of navigating a namespace via e.g. :service, then :pod etc, I would like to see everything that's in the namespace in a single view. As if you would type kubectl -n argocd get all.
Can't find the info in the docs. Is this even possible?
Thanks for any suggestion!
Posting community wiki answer based on GitHub topic - Show multiple resource types without having to switch. Feel free to expand it.
That's true, there is no information about this in the documentation because simply there is no such possibility. There is open issue with this request on the GitHub page of k9s:
Is your feature request related to a problem? Please describe.
Oftentimes I'm watching/working on multiple resource types at the same time and it's very helpful to not have to switch from one to another. This is something very like kubectl get pod,deploy,... or kubectl get-all commands allows
Describe the solution you'd like
Being able to see multiple or all resources in the same screen without having to switch between resource types like:
:pod,configmap shows all pods & configmaps in the current namespace
or
:all shows all resources in the current namespace (get-all like)
Last pinged November 4 2021.
You can try
kubectl get all -n argocd -o yaml
or
kubectl get all -n argocd -o json
to list all common resources in a particular namespace
Note: It will not list the CRD or other custom resources like helm
Related
I am studying "kubectl describe" sourcecodes at https://github.com/kubernetes/kubectl/blob/master/pkg/describe/describe.go
However, I still could not figure out how "kubectl decsribe [CRD]" works (as in which function/functions are called).
I am a Go newbie, so would like to get some pointers please. Thanks.
I have read describePod function and understand how it works more or less, but still could not figure out how "kubectl describe [CRD]" works.
The "kubectl describe " function can be found in the command-line interface (CLI) of Kubernetes, specifically in the "kubectl" tool. "kubectl" is used to manage and interact with a Kubernetes cluster and its resources.
enter image description here
Kubectl describe command helps to view the entire information about the kubernetes resources like Pods,deployments,services,nodes,jobs etc.
By using CRD(Custom Resource Definition) you can do CRUD operations like create, update, get and delete commands to access the resources. To use CRD we need to use the API groups.
Example:
Suppose you specify an API group as example.crd.com, which means you can issue the get, list, create, update, and delete commands to access the custom resources under the API group example.crd.com.
You can use kubectl describe crd <crd_name> to get a description of the CRD.
For more information refer this official doc
Try this similar SO’s SO1 and SO2 for more information
I am working with kubernetes and kubectl commands, and am able to get a list of namespaces, and then can get the resources inside those namespaces. Question is, is there an effective way to monitor all resources (CRDs especially) in a certain namespace for changes? I know I could do this:
kubectl get myobjecttype -n <user-account-1>
and then check timestamps with a separate command, but that seems resource-taxing.
You might be looking for the Kubernetes Watch API.
In fact, you make a List request (see API reference for e.g. Pods) and add the watch=1 query parameter to get a continuous stream of changes to the specified resources.
kubectl also supports watches with the -w/--watch flag:
kubectl get myobjecttype -n <user-account-1> -w
Is there a simple method (that won't require googling at every use) to get names of all deployment configs with no running pods (scaled to 0) in Kubernetes / Openshift? Methods without JSON tokens and awk please.
The docs of oc get dc --help are way too long to decipher for the occasional need.
The only CLI arg for advanced filtering without working with JSON is a --field-selector, but it has a limited scope which not include spec.replicas field.
So, there will be some magic around JSON with other flag - jsonpath.
Here is a command to filter and print names of all deployments which are scaled to 0:
kubectl get deployments --all-namespaces -o=jsonpath='{range .items[?(#.spec.replicas==0)]}{.metadata.name}{"\n"}{end}'
Jsonpath reference is here.
Is there a easy way to list all kubernetes objects related to an API version?
Lets say, API version apps/v1beta1 is getting deprecated and I want to know if I have any objects in my cluster using this version, how can I find such objects?
you can do something similar like this
kubectl get pod -o=custom-columns=NAME:.metadata.name,API-version:.metadata.owner_references[].api_version
by using kubectl just print respective data and api version
The reason I asked this question was that I was upgrading my kubernetes cluster from v1.15 to v1.16 and this brings a lot of breaking changes
The kubepug tool allowed me to easily find a list of resources that I need to change to be able to upgrade seamlessly from 1.15 to 1.16
Edit:
Another alternative is pluto command line tool to get information about resources which might have deprecated or removed API versions. This is helpful specially if you use helm extensively since pluto can look at helm state.
To list Kubernetes resource versions use this command:
kubectl api-resources
And if the you know what resource you are searching for then just filter it from the list using grep:
kubectl api-resources | grep the_resource_name_you_want
In the below example we search for the api version of 'persistentvolumes' resource:
kubectl api-resources | grep persistentvolumes
Result:
deployments deploy apps/v1 true Deployment
There are additional options to get the resource version:
Use the official documentation:
The official and updated with the newest versions is in the Kubernetes API documentation
The left navigation bar lists the resources, click on one & the version is the first row of the page.
First off, I'm completely new with Kubernetes so I may have missed something completely obvious but the documentation is exactly helping, so I'm turning to you guys for help.
I'm trying to figure out just how many types of "deployment files" there are for Kubernetes. I call them "deployment files" because I really don't know what else to call them and they're usually associated with a deployment.
So far, every yml/yaml file I've seen start like this:
apiVersion:
kind: << this is what I'm asking about >>
metadata:
And so far I have seen this many "kind"(s)
ClusterConfig
ClusterRole
ClusterRoleBinding
CronJob
Deployment
Job
PersistentVolumeClaim
Pod
ReplicationController
Role
RoleBinding
Secret
Service
ServiceAccount
I'm sure there are many more. But I can't seem to find a location where they are listed and the contexts broken down.
So what I want to know is this,
Where can I find an explanation for these yaml files?
Where can I learn about the different kinds?
Where can I get a broken down explanation of the minimum required fields/values are for any of these?
Are there templates for these files?
Thanks
This question will need a blog to answer but still in short you can try these options and command to learn from your kubectl CLI.
Learn to use kubectl explain command which shows you a list of Kubernetes objects:
$ kubectl explain
You can get detailed information about any of listed resources using this syntax
`$ kubectl explain pod
$ kubectl explain pod.spec
$ kubectl explain pod.spec.containers`
Or you can get yam template of the object by adding --recursive flag to explain command.
$ kubectl explain pod --recursive
This will also give you official document link.
So in short running kubectl explain with recursive option will list every thing.
When you are talking about specific yaml file containing the definition of specific kubernetes object, you can call them yaml manifests or simply yaml definition files. Using word Deployment for all of them isn't a good idea as there is already specific resource type defined and called by this name in kubernetes. So it's better you don't call them all deployments for consistency.
I'm sure there are many more. But I can't seem to find a location
where they are listed and the contexts broken down.
Yes, there are a lot more of them and you can list those which are available by running:
kubectl api-resources
These different objects are actually called api-resources. As you can see they are listed in three columns: NAME, SHORTNAMES, APIGROUP, NAMESPACED and KIND
NAME SHORTNAMES APIGROUP NAMESPACED KIND
bindings true Binding
componentstatuses cs false ComponentStatus
configmaps cm true ConfigMap
endpoints ep true Endpoints
events ev true Event
limitranges limits true LimitRange
namespaces ns false Namespace
nodes no false Node
Note that the name of resource corresponds to its KIND but it is slightly different. NAME simply describes resource types as we are referring to them e.g. using kubectl command line utility. Just to give one example, when you want to list pods available in your cluster you simply type kubectl get pods. You don't have to use resource kind i.e. Pod in this context. You can but you don't have to. So kubectl get Pod or kubectl get ConfigMap will also return desired result. You can also refer to them by their shournames so kubectl get daemonsets and kubectl get ds are equivalent.
It's totally different when it comes to specific resource/object definition. In context of yaml definition file we must to use proper KIND of the resource. They are mostly start with capital letter and are written by co called CamelCase but there are exceptions from this rule.
I really recommend you to familiarize with kubernetes documentation. It is very user-friendly and nicely explains both key kubernetes concepts as well as all very tiny details.
Here you have even more useful commands for exploring API resources:
kubectl api-resources --namespaced=true # All namespaced resources
kubectl api-resources --namespaced=false # All non-namespaced resources
kubectl api-resources -o name # All resources with simple output (just the resource name)
kubectl api-resources -o wide # All resources with expanded (aka "wide") output
kubectl api-resources --verbs=list,get # All resources that support the "list" and "get" request verbs
kubectl api-resources --api-group=extensions # All resources in the "extensions" API group
As #wargre already suggested in his comment, kubernetes official documentetion is definitely the best place to start as you will find there very detailed description of every resource.
Understanding Kubernetes Objects
You may start from reading this article: Understanding Kubernetes Objects
Kubernetes Objects are persistent entities in the Kubernetes system. Kubernetes uses these entities to represent the state of your cluster. Specifically, they can describe:
What containerized applications are running (and on which nodes)
The resources available to those applications
The policies around how those applications behave, such as restart policies, upgrades, and fault-tolerance
A Kubernetes object is a “record of intent”–once you create the object, the Kubernetes system will constantly work to ensure that object exists. By creating an object, you’re effectively telling the Kubernetes system what you want your cluster’s workload to look like; this is your cluster’s desired state.
K8s API reference
A detailed description of all objects can be found in the Kubernetes API reference guide.