I have a 6 minion cluster and would like to know how many of these minions are actually hosting pods at any given time. Is there a specific command for that ? Right now Im using a very generic command.
kubectl get po | grep Running > RUNNING.txt
for i in `cat RUNNING.txt `; do kubectl describe po $i; done | grep "Started container with docker
"
Any direct command to fetch the info I want ?
Just add -o wide:
kubectl get pod -o wide
This command will print all the nodes that have pods running on them:
kubectl get pods -o jsonpath='{range .items[*]}{.spec.nodeName} {end}' | tr " " "\n" | sort | uniq
Related
I want to list a node's pods and pod statues, eg.
Node A
Pod1 Status
Pod2 Status
Node B
Pod1 Status
Pod2 Status
Is there a kubectl command I can use for this?
kubectl get pods
will give you almost what you want, but it has no Node information, that is why you would need -o wide (I doubt you really want the -A parameter here); then you need a bit of awk. So may be like this:
kubectl get pods -o wide | awk '{print $1" "$3" "$7}
This script gives exactly the output you want:
kubectl get --no-headers pods --all-namespaces -o wide > /tmp/allpods
while read node; do
echo "${node/node\//}"
grep " ${node/node\//} " /tmp/allpods | \
while read line; do
set -- $line
echo "$2 $4"
done
done < <(kubectl get nodes --no-headers --output=name)
But this version has a more readable output in my opinion:
first column: k8s node name
second column: namespace/pod-name
third column: pod status
kubectl get --no-headers pods --all-namespaces -o wide > /tmp/allpods
while read node; do
echo "${node/node\//}"
while read line; do
set -- $line
echo " $2 $4"
done < <(grep " ${node/node\//} " /tmp/allpods)
done < <(kubectl get nodes --no-headers --output=name) | column -t -s ' '
Output:
k8s-node01
my-namespace01/mypod01-321-86d58674d8-kv222 Completed
my-namespace01/mypod01-321-redis-55dc88454c-z6xfj Running
[...]
k8s-node02
[...]
Doing an API call for each cluster node, as the accepted answer suggests, makes the script execution very long in a production environment with dozens of nodes and thousands of pods. That's why I opted for a solution where the result of a single call is saved to a temporary file.
Try this:
kubectl get pods -A --field-selector spec.nodeName=<node name> | awk '{print $2" "$4}'
Is there a way to get top pods filtered by node?
Use case: I have a node which is reported to use 103% of the cpu and I want to validate which pods are causing it.
I don't think there is direct way to do it with kubectl top pods command since the only option to filter is label/selector which apply to pod only.
For your use case, you can use the command:
kubectl get pods -o wide | grep <node> | awk {'print $1'} | xargs -n1 command kubectl top pods --no-headers
kubectl get pods -o wide: display pods with their associated node information
grep <node>: let you filter pod located on a specific node
awk {'print $1'}: print the first column (name of the pods)
xargs -n1 command kubectl top pods --no-headers: execute the top command for each pod without the headers (NAME, CPU, MEMORY)
Additionally, you can check the limits you've set for each pod in one specific node using the command kubectl describe node <node>
For powershell users, just set your <node_name> to filter
kubectl get pods -o wide --all-namespaces | sls "<node_name>" | ForEach-Object {$row = ($_ -split "\s+"); $top = ("kubectl -n $($row[0]) top pod $($row[1]) --no-headers --containers" | iex); foreach($line in $top){$container=$line -split "\s+"; [pscustomobject]#{node=$nodeName; pod=$container[0];container=$container[1];cpu=$container[2];memory=$container[3]}} } | Sort-Object pod| ft -AutoSize
I'm looking for a command like "gcloud config get-value project" that retrieves a project's name, but for a pod (it can retrieve any pod name that is running). I know you can get multiple pods with "kubectl get pods", but I would just like one pod name as the result.
I'm having to do this all the time:
kubectl get pods # add one of the pod names in next line
kubectl logs -f some-pod-frontend-3931629792-g589c some-app
I'm thinking along the lines of "gcloud config get-value pod". Is there a command to do that correctly?
There are many ways, here are some examples of solutions:
kubectl get pods -o name --no-headers=true
kubectl get pods -o=name --all-namespaces | grep kube-proxy
kubectl get pods -o go-template --template '{{range .items}}{{.metadata.name}}{{"\n"}}{{end}}'
For additional reading, please take a look to these links:
kubernetes list all running pods name
Kubernetes list all container id
https://kubernetes.io/docs/tasks/access-application-cluster/list-all-running-container-images/
You can use the grep command to filter any output on stdout. So to get pods matching a specified pattern you can use a command like this:
> kubectl get pods --all-namespaces|grep grafana
Output:
monitoring kube-prometheus-grafana-57d5b4d79f-smkz6 2/2 Running 0 1h
To only output the pod name, you can use the awk command with a parameter of '{print $2}', which displays the second column of the previous output:
kubectl get pods --all-namespaces|grep grafana|awk '{print $2}'
To only display one line you can use the head command like so:
kubectl get pods --all-namespaces|grep grafana|awk '{print $2}'|head -n 1
This will output the last pod name :
kubectl get pods -o go-template --template ' {{range .items}}{{.metadata.name}}{{"\n"}}{{end}}' | awk '{print $1}' | tail -n 1
if you want to fetch logs for a pod:
kubectl logs -f kubectl get pods -o go-template --template ' {{range .items}}{{.metadata.name}}{{"\n"}}{{end}}' | awk '{print $1}' | tail -n 1
just run the command with a single quotes.
Links:
kubernetes list all running pods name
https://kubernetes.io/docs/tasks/access-application-cluster/list-all-running-container-images/
Hope this helps!!
I've found jsonpath examples for testing multiple values but not extracting multiple values.
I want to get image and name from kubectl get pods.
this gets me name
kubectl get pods -o=jsonpath='{.items[*].spec.containers[*].name}' | xargs -n 1
this gets me image
kubectl get pods -o=jsonpath='{.items[*].spec.containers[*].image}' | xargs -n 1
but
kubectl get pods -o=jsonpath='{.items[*].spec.containers[*].[name,image}' | xargs -n 2
complains invalid array index image - is there a syntax for getting a list of node-adjacent values?
Use below command to get name and image:
kubectl get pods -Ao jsonpath='{range .items[*]}{#.metadata.name}{" "}{#.spec.template.spec.containers[].image}{"\n"}{end}'
It will give output like below:
name image
Useful command, I had to modify it a little to make it work (failed with -a flag). Also, I added a filter to app label and one more field to get: namespace, pod name, image
kubectl get pods --all-namespaces -o jsonpath='{range .items[*]}{#.metadata.namespace}{"\t"}{#.metadata.name}{"\t"}{#.spec.containers[*].image}{"\n"}{end}' -l app=nginx
Thanks! I had to change a little bit, but this worked for me:
#!/bin/bash
releases=$(kubectl get deployment -A --output=jsonpath='{range .items[*]}{#.metadata.namespace}{"|"}{#.metadata.name}{"\n"}{end}')
for release in $releases; do
namespace=$( echo $release | cut -d "|" -f 1)
deployment=$( echo $release | cut -d "|" -f 2)
kubectl rollout restart deployments -n "${namespace}" "${deployment}"
done
I looking for the option to list all pods name
How to do without awk (or cut). Now i'm using this command
kubectl get --no-headers=true pods -o name | awk -F "/" '{print $2}'
Personally I prefer this method because it relies only on kubectl, is not very verbose and we don't get the pod/ prefix in the output:
kubectl get pods --no-headers -o custom-columns=":metadata.name"
You can use the go templating option built into kubectl to format the output to just show the names for each pod:
kubectl get pods --template '{{range .items}}{{.metadata.name}}{{"\n"}}{{end}}'
Get Names of pods using -o=name Refer this cheatsheet for more.
kubectl get pods -o=name
Example output:
pod/kube-xyz-53kg5
pod/kube-xyz-jh7d2
pod/kube-xyz-subt9
To remove trailing pod/ you can use standard bash sed command
kubectl get pods -o=name | sed "s/^.\{4\}//"
Example output:
kube-xyz-53kg5
kube-pqr-jh7d2
kube-abc-s2bt9
To get podname with particular string, standard linux grep command
kubectl get pods -o=name | grep kube-pqr | sed "s/^.\{4\}//"
Example output:
kube-pqr-jh7d2
With this name, you can do things, like adding alias to get shell to running container:
alias bashkubepqr='kubectl exec -it $(kubectl get pods -o=name | grep kube-pqr | sed "s/^.\{4\}//") bash'
You can use custom-columns in output option to get the name and --no-headers option
kubectl get --no-headers=true pods -l app=external-dns -o custom-columns=:metadata.name
You can use -o=name to display only pod names. For example to list proxy pods you can use:
kubectl get pods -o=name --all-namespaces | grep kube-proxy
The result is:
pod/kube-proxy-95rlj
pod/kube-proxy-bm77b
pod/kube-proxy-clc25
There is also this solution:
kubectl get pods -o jsonpath={..metadata.name}
Here is another way to do it:
kubectl get pods -o=name --field-selector=status.phase=Running
The --field-selector=status.phase=Running is needed as the question mention all the running pod names. If the all in the question is for all the namespaces, just add the --all-namespaces option.
Note that this command is very convenient when one want a quick way to access something from the running pod(s), such as logs :
kubectl logs -f $(kubectl get pods -o=name --field-selector=status.phase=Running)
Get all running pods in the namespace
kubectl get pods --field-selector=status.phase=Running --no-headers -o custom-columns=":metadata.name"
From viewing, finding resources.
You could also specify namespace with -n <namespace name>.
jsonpath alternative
kubectl get po -o jsonpath="{range .items[*]}{#.metadata.name}{end}" -l app=nginx-ingress,component=controller
see also:
more examples of kubectl output options
If you want to extract specific container's pod name then
A simple command can do all the hard work
kubectl get pods --template '{{range .items}}{{.metadata.name}}{{end}}' --selector=app=<CONTAINER-NAME>
Just replace <CONTAINER-NAME> with your service container-name
Well, In our case we have kept pods inside different namespace, here to identify the specific pod or list of pods we ran following command-
Approach 1:
To get the list of namespaces
kubectl get ns -A
To get all the pods inside one namespaces kubectl get pods -n <namespace>
Approach 2:
Use this command-
kubectl get pods --all-namespaces
kubectl exec -it $(kubectl get pods | grep mess | awk '{print $1}') /bin/bash
kubectl get po --all-namespaces | awk '{if ($4 != "Running") system ("kubectl -n " $1 " delete pods " $2 " --grace-period=0 " " --force ")}'