Get a Shell to a Running Container [page]deterministic
This page shows how to use `kubectl exec` to get a shell to a running container.
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## Getting a shell to a container
In this exercise, you create a Pod that has one container. The container runs the nginx image. Here is the configuration file for the Pod:
Create the Pod:
```shell kubectl apply -f https://k8s.io/examples/application/shell-demo.yaml ```
Verify that the container is running:
```shell kubectl get pod shell-demo ```
Get a shell to the running container:
```shell kubectl exec --stdin --tty shell-demo -- /bin/bash ```
> Note: The double dash (`--`) separates the arguments you want to pass to the command from the kubectl arguments.
In your shell, list the root directory:
```shell # Run this inside the container ls / ```
In your shell, experiment with other commands. Here are some examples:
```shell # You can run these example commands inside the container ls / cat /proc/mounts cat /proc/1/maps apt-get update apt-get install -y tcpdump tcpdump apt-get install -y lsof lsof apt-get install -y procps ps aux ps aux | grep nginx ```
## Writing the root page for nginx
Look again at the configuration file for your Pod. The Pod has an `emptyDir` volume, and the container mounts the volume at `/usr/share/nginx/html`.
In your shell, create an `index.html` file in the `/usr/share/nginx/html` directory:
```shell # Run this inside the container echo 'Hello shell demo' > /usr/share/nginx/html/index.html ```
In your shell, send a GET request to the nginx server:
```shell # Run this in the shell inside your container apt-get update apt-get install curl curl http://localhost/ ```
The output shows the text that you wrote to the `index.html` file:
``` Hello shell demo ```
When you are finished with your shell, enter `exit`.
```shell exit # To quit the shell in the container ```
## Running individual commands in a container
In an ordinary command window, not your shell, list the environment variables in the running container:
```shell kubectl exec shell-demo -- env ```
Experiment with running other commands. Here are some examples:
```shell kubectl exec shell-demo -- ps aux kubectl exec shell-demo -- ls / kubectl exec shell-demo -- cat /proc/1/mounts ```
## Opening a shell when a Pod has more than one container
If a Pod has more than one container, use `--container` or `-c` to specify a container in the `kubectl exec` command. For example, suppose you have a Pod named my-pod, and the Pod has two containers named _main-app_ and _helper-app_. The following command would open a shell to the _main-app_ container.
```shell kubectl exec -i -t my-pod --container main-app -- /bin/bash ```
> Note: The short options `-i` and `-t` are the same as the long options `--stdin` and `--tty`
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* Read about [kubectl exec](/docs/reference/generated/kubectl/kubectl-commands/#exec)