I have this command
clear; sudo kubectl exec -it $(kubectl get pods | grep 'app' | cut -d ' ' -f 1) ash
I will land here
/src #
I want to also run a command ls
/src # ls
Procfile composer.lock phpunit.xml server.php
app config public storage
artisan database resources tests
benu.code-workspace heroku.sh routes vendor
bootstrap package-lock.json run.sh webpack.mix.js
composer.json package.json scripts
/src #
I've tried
clear; sudo kubectl exec -it $(kubectl get pods | grep 'app' | cut -d ' ' -f 1) ash echo "ls"
and
clear; sudo kubectl exec -it $(kubectl get pods | grep 'app' | cut -d ' ' -f 1) echo "ls"
Please correct me
If you want to run the command, you want kubectl exec -it $podname ls. If you put echo "ls" then that is the command which run, i.e. print "ls".
Related
I have few pods running in my kubernetes cluster. I am developing a shell script and I want to grep for few pods and want to select each pod from the grep result to execute a command.
Lets say I grep few pods by command :
kubectl get pods | grep test
the results are:
Test-0
Test-1
Test-2
From the result, I want to select each pod and execute a command for it in a loop.
for example:
for first pod:
kubectl exec -it Test-0 -- mysqldump.......
after finishing the first pod, it has to process the second pod and so on
for pod in $(kubectl get pod -oname |grep -i Test ); do
kubectl exec "$pod" -- ls -ltr ;
done
Replace ls -ltr with mysqldump .....
Get pods name and then use "for" to execute command in each pod
#!/bin/bash
pods=$(kubectl get pods | awk '{print $2}' | grep -i test)
for i in $pods
do
kubectl exec -it $i -- echo "test"
done
Select your target pods using labels is less error prone and can do multiple matching:
kubectl get pods --selector <key>=<value>,<key>=<value> --namespace <name> -oname | xargs -I{} kubectl exec -it {} --namespace <name> -- mysqldump ...
I want to run a local script within Kubernetes pod and then set the output result to a linux variable
Here is what I tried:
# if I directly run -c "netstat -pnt |grep ssh", I get output assigned to $result:
cat check_tcp_conn.sh
#!/bin/bash
result=$(kubectl exec -ti <pod_name> -- /bin/bash -c "netstat -pnt |grep ssh")
echo "result is $result"
What I want is something like this:
#script to be called:
cat netstat_tcp_conn.sh
#!/bin/bash
netstat -pnt |grep ssh
#script to call netstat_tcp_conn.sh:
cat check_tcp_conn.sh
#!/bin/bash
result=$(kubectl exec -ti <pod_name> --
/bin/bash -c "./netstat_tcp_conn.sh)
echo "result is $result
the result showed result is /bin/bash: ./netstat_tcp_conn.sh: No such file or directory.
How can I let Kubernetes pod execute netstat_tcp_conn.sh which is at my local machine?
You can use following command to execute your script in your pod:
kubectl exec POD -- /bin/sh -c "`cat netstat_tcp_conn.sh`"
You can copy local files into pod using kubectl command like kubectl cp /tmp/foo :/tmp/
Then you can change its permission and make it executable and run it using kubectl exec.
my goal is to execute a script once on a permanently running pod in kubernetes. The pod is called busybox-<SOME_ID> and finds itself in the namespace default.Therefore, I wrote this script - called scan-one-pod.sh:
#!/bin/bash
export MASTER_IP=192.168.56.102
export SCRIPT_NAME=script.sh
export POD_NAMESPACE=default
export POD_NAME=busybox
echo "echo HALLO" | ssh ubuntu#$MASTER_IP
export POD_ID=$(kubectl get po | grep busybox | sed -n '1p'|awk '{print $1}')
kubectl cp $SCRIPT_NAME $POD_NAMESPACE/$POD_ID:.
kubectl exec $POD_ID -- chmod +x $SCRIPT_NAME
export CONTAINER_ID=$(kubectl describe pod busybox | grep 'Container ID' | sed -n '1p'|awk '{print $3}')
ssh -t ubuntu#$MASTER_IP "sudo docker exec -u root $CONTAINER_ID -- ./script.sh"
The referred script script.sh has the following content:
$ kubectl exec $POD_ID -- cat script.sh
#!/bin/bash
echo "test" >> test
cp test test-is-working
However, it is not possible to run the script on the pod:
the files test and test-is-working are not created
the script scan-one-pod.sh returns just EOF:
$ ./scan-one-pod.sh
Pseudo-terminal will not be allocated because stdin is not a terminal.
Welcome to Ubuntu 16.04.3 LTS (GNU/Linux 4.4.0-87-generic x86_64)
* Documentation: https://help.ubuntu.com
* Management: https://landscape.canonical.com
* Support: https://ubuntu.com/advantage
155 Software-Pakete können aktualisiert werden.
72 Aktualisierungen sind Sicherheitsaktualisierungen.
HALLO
[sudo] Passwort für ubuntu:
EOF
Connection to 192.168.56.102 closed.
If I execute the docker-command directly, remote on my kubernetes-controller, I get the same message of EOF:
ubuntu#controller:~$ export CONTAINER_ID=$(kubectl describe pod busybox | grep 'Container ID' | sed -n '1p'|awk '{print $3}')
ubuntu#controller:~$ sudo docker exec -u root $CONTAINER_ID ./script.sh
EOF
If I execute it from my local workstation via kubectl exec I get this error:
$ kubectl exec $POD_ID ./script.sh
rpc error: code = 13 desc = invalid header field value "oci runtime error: exec failed: container_linux.go:247: starting container process caused \"no such file or directory\"\n"
I don't know, which missing file they are referring to, but the script.sh-file is present and the busybox-pod seems to be running:
$ kubectl exec $POD_ID ls script.sh
script.sh
$ kubectl get po busybox-6bdf9b5bbc-4skds
NAME READY STATUS RESTARTS AGE
busybox-6bdf9b5bbc-4skds 1/1 Running 10 12d
Question: As far as I know, EOF means End-Of-File. End of which file would be important for me to know, and why is that a problem?
Thanks in advance, any help is appreciated :)
Is there any shortcut command to connect to a docker container without running docker exec -it 'container_id' bash every time?
Here is a shorter command line shortcut to:
Check if a container is running
If running, connect to a running container using docker exec -it <container> bash command:
Script docker-enter:
#!/bin/bash
name="${1?needs one argument}"
containerId=$(docker ps | awk -v app="$name:" '$2 ~ app{print $1}')
if [[ -n "$containerId" ]]; then
docker exec -it $containerId bash
else
echo "No docker container with name: $name is running"
fi
Then run it as:
docker-enter webapp
I'm using the following alias on OS X:
alias dex='function _dex(){ docker exec -i -t "$(basename $(pwd) | tr -d "[\-_]")_$1_1" /bin/bash -c "export TERM=xterm; exec bash" };_dex'
In the same directory as my docker-files, I run "dex php" to enter the PHP container.
If random id is complicated. Start container with name docker run --name test image and connect with its name docker exec -it test bash.
How to use this command in windows 10 familly :
docker-compose run api composer install --no-interaction
Example:
docker-compose run api composer install --no-interaction
- Interactive mode is not yet supported on Windows.
Please pass the -d flag when using `docker-compose run`.
Is it possible ?
Do you have an example ?
The interactive mode support for docker-compose on Windows is tracked by issue 2836 which proposes some alternatives:
Use bash from within the container:
docker exec -it MY_CONTAINER bash
Use a docker-compose-run script by Rodrigo Baron:
Script ( put the function in ~/.zshrc or ~/.bashrc in a Windows git bash shell for instance):
#!/bin/bash
function docker-compose-run() {
if [ "$1" = "-f" ] || [ "$1" = "--file" ] ; then
docker exec -i $(docker-compose -f $2 ps $3 |grep -m 1 $3 | cut -d ' ' -f1) "${#:4}"
else
docker exec -i $(docker-compose ps $1 | grep -m 1 $1 | cut -d ' ' -f1) "${#:2}"
fi
}
docker-compose-run "$#"
Usage:
usage:
docker-compose-run web rspec
# or:
docker-compose-run -f docker-compose.development.yml web rspec
Simpler alternative is to use option -d and to get logs
docker-compose run -rm <service> <command>
is replaced by:
docker-compose-run <service> <command>
For this to work, add this snippet in your ~/.bashrc :
docker-compose-run() {
CONTAINER_NAME=$(docker-compose run -d $#)
docker logs -f $CONTAINER_NAME
docker rm $CONTAINER_NAME
}