website/content/en/docs/reference/kubectl/docker-cli-to-kubectl.md

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---
title: kubectl for Docker Users
content_template: templates/concept
reviewers:
2016-07-29 17:36:25 +00:00
- bgrant0607
- brendandburns
- thockin
2016-02-10 20:29:07 +00:00
---
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You can use the Kubernetes command line tool kubectl to interact with the API Server. Using kubectl is straightforward if you are familiar with the Docker command line tool. However, there are a few differences between the docker commands and the kubectl commands. The following sections show a docker sub-command and describe the equivalent kubectl command.
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## docker run
To run an nginx Deployment and expose the Deployment, see [kubectl run](/docs/reference/generated/kubectl/kubectl-commands/#run).
docker:
```shell
$ docker run -d --restart=always -e DOMAIN=cluster --name nginx-app -p 80:80 nginx
55c103fa129692154a7652490236fee9be47d70a8dd562281ae7d2f9a339a6db
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
55c103fa1296 nginx "nginx -g 'daemon of…" 9 seconds ago Up 9 seconds 0.0.0.0:80->80/tcp nginx-app
```
kubectl:
```shell
# start the pod running nginx
$ kubectl run --image=nginx nginx-app --port=80 --env="DOMAIN=cluster"
deployment "nginx-app" created
```
{{< note >}}
`kubectl` commands print the type and name of the resource created or mutated, which can then be used in subsequent commands. You can expose a new Service after a Deployment is created.
{{< /note >}}
```shell
# expose a port through with a service
$ kubectl expose deployment nginx-app --port=80 --name=nginx-http
service "nginx-http" exposed
```
By using kubectl, you can create a [Deployment](/docs/concepts/workloads/controllers/deployment/) to ensure that N pods are running nginx, where N is the number of replicas stated in the spec and defaults to 1. You can also create a [service](/docs/concepts/services-networking/service/) with a selector that matches the pod labels. For more information, see [Use a Service to Access an Application in a Cluster](/docs/tasks/access-application-cluster/service-access-application-cluster).
By default images run in the background, similar to `docker run -d ...`. To run things in the foreground, use:
```shell
kubectl run [-i] [--tty] --attach <name> --image=<image>
```
Unlike `docker run ...`, if you specify `--attach`, then you attach `stdin`, `stdout` and `stderr`. You cannot control which streams are attached (`docker -a ...`).
To detach from the container, you can type the escape sequence Ctrl+P followed by Ctrl+Q.
Because the kubectl run command starts a Deployment for the container, the Deployment restarts if you terminate the attached process by using Ctrl+C, unlike `docker run -it`.
To destroy the Deployment and its pods you need to run `kubectl delete deployment <name>`.
## docker ps
To list what is currently running, see [kubectl get](/docs/reference/generated/kubectl/kubectl-commands/#get).
docker:
```shell
$ docker ps -a
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
14636241935f ubuntu:16.04 "echo test" 5 seconds ago Exited (0) 5 seconds ago cocky_fermi
55c103fa1296 nginx "nginx -g 'daemon of…" About a minute ago Up About a minute 0.0.0.0:80->80/tcp nginx-app
```
kubectl:
```shell
2018-11-28 12:55:28 +00:00
$ kubectl get po
NAME READY STATUS RESTARTS AGE
nginx-app-8df569cb7-4gd89 1/1 Running 0 3m
ubuntu 0/1 Completed 0 20s
```
## docker attach
To attach a process that is already running in a container, see [kubectl attach](/docs/reference/generated/kubectl/kubectl-commands/#attach).
docker:
```shell
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
55c103fa1296 nginx "nginx -g 'daemon of…" 5 minutes ago Up 5 minutes 0.0.0.0:80->80/tcp nginx-app
$ docker attach 55c103fa1296
...
```
kubectl:
```shell
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
nginx-app-5jyvm 1/1 Running 0 10m
$ kubectl attach -it nginx-app-5jyvm
...
```
To detach from the container, you can type the escape sequence Ctrl+P followed by Ctrl+Q.
## docker exec
To execute a command in a container, see [kubectl exec](/docs/reference/generated/kubectl/kubectl-commands/#exec).
docker:
```shell
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
55c103fa1296 nginx "nginx -g 'daemon of…" 6 minutes ago Up 6 minutes 0.0.0.0:80->80/tcp nginx-app
$ docker exec 55c103fa1296 cat /etc/hostname
55c103fa1296
```
kubectl:
```shell
$ kubectl get po
NAME READY STATUS RESTARTS AGE
nginx-app-5jyvm 1/1 Running 0 10m
$ kubectl exec nginx-app-5jyvm -- cat /etc/hostname
nginx-app-5jyvm
```
To use interactive commands.
docker:
```shell
$ docker exec -ti 55c103fa1296 /bin/sh
# exit
```
kubectl:
```shell
$ kubectl exec -ti nginx-app-5jyvm -- /bin/sh
# exit
```
For more information, see [Get a Shell to a Running Container](/docs/tasks/debug-application-cluster/get-shell-running-container/).
## docker logs
To follow stdout/stderr of a process that is running, see [kubectl logs](/docs/reference/generated/kubectl/kubectl-commands/#logs).
docker:
```shell
$ docker logs -f a9e
192.168.9.1 - - [14/Jul/2015:01:04:02 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.35.0" "-"
192.168.9.1 - - [14/Jul/2015:01:04:03 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.35.0" "-"
```
kubectl:
```shell
$ kubectl logs -f nginx-app-zibvs
10.240.63.110 - - [14/Jul/2015:01:09:01 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.26.0" "-"
10.240.63.110 - - [14/Jul/2015:01:09:02 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.26.0" "-"
```
There is a slight difference between pods and containers; by default pods do not terminate if their processes exit. Instead the pods restart the process. This is similar to the docker run option `--restart=always` with one major difference. In docker, the output for each invocation of the process is concatenated, but for Kubernetes, each invocation is separate. To see the output from a previous run in Kubernetes, do this:
```shell
$ kubectl logs --previous nginx-app-zibvs
10.240.63.110 - - [14/Jul/2015:01:09:01 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.26.0" "-"
10.240.63.110 - - [14/Jul/2015:01:09:02 +0000] "GET / HTTP/1.1" 200 612 "-" "curl/7.26.0" "-"
```
For more information, see [Logging Architecture](/docs/concepts/cluster-administration/logging/).
## docker stop and docker rm
To stop and delete a running process, see [kubectl delete](/docs/reference/generated/kubectl/kubectl-commands/#delete).
docker:
```shell
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
a9ec34d98787 nginx "nginx -g 'daemon of" 22 hours ago Up 22 hours 0.0.0.0:80->80/tcp, 443/tcp nginx-app
$ docker stop a9ec34d98787
a9ec34d98787
$ docker rm a9ec34d98787
a9ec34d98787
```
kubectl:
```shell
$ kubectl get deployment nginx-app
NAME DESIRED CURRENT UP-TO-DATE AVAILABLE AGE
nginx-app 1 1 1 1 2m
$ kubectl get po -l run=nginx-app
NAME READY STATUS RESTARTS AGE
nginx-app-2883164633-aklf7 1/1 Running 0 2m
$ kubectl delete deployment nginx-app
deployment "nginx-app" deleted
$ kubectl get po -l run=nginx-app
# Return nothing
```
{{< note >}}
When you use kubectl, you don't delete the pod directly.You have to first delete the Deployment that owns the pod. If you delete the pod directly, the Deployment recreates the pod.
{{< /note >}}
## docker login
There is no direct analog of `docker login` in kubectl. If you are interested in using Kubernetes with a private registry, see [Using a Private Registry](/docs/concepts/containers/images/#using-a-private-registry).
## docker version
To get the version of client and server, see [kubectl version](/docs/reference/generated/kubectl/kubectl-commands/#version).
docker:
```shell
$ docker version
Client version: 1.7.0
Client API version: 1.19
Go version (client): go1.4.2
Git commit (client): 0baf609
OS/Arch (client): linux/amd64
Server version: 1.7.0
Server API version: 1.19
Go version (server): go1.4.2
Git commit (server): 0baf609
OS/Arch (server): linux/amd64
```
kubectl:
```shell
$ kubectl version
Client Version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.9+a3d1dfa6f4335", GitCommit:"9b77fed11a9843ce3780f70dd251e92901c43072", GitTreeState:"dirty", BuildDate:"2017-08-29T20:32:58Z", OpenPaasKubernetesVersion:"v1.03.02", GoVersion:"go1.7.5", Compiler:"gc", Platform:"linux/amd64"}
Server Version: version.Info{Major:"1", Minor:"6", GitVersion:"v1.6.9+a3d1dfa6f4335", GitCommit:"9b77fed11a9843ce3780f70dd251e92901c43072", GitTreeState:"dirty", BuildDate:"2017-08-29T20:32:58Z", OpenPaasKubernetesVersion:"v1.03.02", GoVersion:"go1.7.5", Compiler:"gc", Platform:"linux/amd64"}
```
## docker info
To get miscellaneous information about the environment and configuration, see [kubectl cluster-info](/docs/reference/generated/kubectl/kubectl-commands/#cluster-info).
docker:
```shell
$ docker info
Containers: 40
Images: 168
Storage Driver: aufs
Root Dir: /usr/local/google/docker/aufs
Backing Filesystem: extfs
Dirs: 248
Dirperm1 Supported: false
Execution Driver: native-0.2
Logging Driver: json-file
Kernel Version: 3.13.0-53-generic
Operating System: Ubuntu 14.04.2 LTS
CPUs: 12
Total Memory: 31.32 GiB
Name: k8s-is-fun.mtv.corp.google.com
ID: ADUV:GCYR:B3VJ:HMPO:LNPQ:KD5S:YKFQ:76VN:IANZ:7TFV:ZBF4:BYJO
WARNING: No swap limit support
```
kubectl:
```shell
$ kubectl cluster-info
Kubernetes master is running at https://108.59.85.141
2017-03-09 18:12:17 +00:00
KubeDNS is running at https://108.59.85.141/api/v1/namespaces/kube-system/services/kube-dns/proxy
kubernetes-dashboard is running at https://108.59.85.141/api/v1/namespaces/kube-system/services/kubernetes-dashboard/proxy
2017-03-09 18:12:17 +00:00
Grafana is running at https://108.59.85.141/api/v1/namespaces/kube-system/services/monitoring-grafana/proxy
Heapster is running at https://108.59.85.141/api/v1/namespaces/kube-system/services/monitoring-heapster/proxy
InfluxDB is running at https://108.59.85.141/api/v1/namespaces/kube-system/services/monitoring-influxdb/proxy
```
2018-11-28 12:55:28 +00:00
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