Utility for copying a running Kubernetes pod so you can run commands in a copy
of its environment, without worrying about it the pod potentially being removed
due to a deploy.
copypod can work in two different modes, depending on if the
flag is provided:
- If the flag is left out,
copypodwill copy the specified pod and start
it. When the pod reaches the “Running” state the name of the pod will be
outputted as the only output. This is intended for use in automation
- If a command is provided with the
--interactiveflag, then the pod will
be copied and started as before, but when the pod is running
be called and connect to the pod where the provided command is then run
interactively. When the
kubectlprogram exits the pod will be removed.
This is intended for running ad-hoc tasks and processes.
You can either install
copypod into a virtual environment directly with:
pip install git+ssh://[email protected]/Memrise/copypod.git
then the program will be available as
copypod inside the virtual environment,
or you can install it by cloning this repository and then use
pipenv to set
up a virtual environment where it will get installed into:
git clone [email protected]:Memrise/copypod.git cd copypod/ pipenv install
Then you can run the program with
pipenv run copypod.
$ copypod --help usage: copypod [-h] [--context CONTEXT] [-n NAMESPACE] (-l SELECTOR | -p POD) [--container CONTAINER] [-c COMMAND] [-i INTERACTIVE] Copy a Kubernetes pod and run commands in its environment. optional arguments: -h, --help show this help message and exit --context CONTEXT Kubectl context to use for configuration (default: None) -n NAMESPACE, --namespace NAMESPACE Namespace for where the source pod is located (default: default) -l SELECTOR, --selector SELECTOR Label selector of pod to copy (default: None) -p POD, --pod POD Name of the pod to copy (default: None) --container CONTAINER Name of container to copy, only needed if the pod has more than one container (default: None) -c COMMAND, --command COMMAND Initial command to run in the copied pod (default: sleep infinity) -i INTERACTIVE, --interactive INTERACTIVE Command to run in an interactive console (default: None) --image IMAGE Copy the entire environment of the pod but use this Docker image instead (default: None) If the `--interactive` flag is provided, the copied pod will be removed immediately after the command exits, otherwise the name of the pod will be printed.
Say you wanted to copy the pod named
my-great-pod and have the copied pod run
until you specifically remove it, you could run:
$ copypod -p my-great-pod pod-copy-girwak
pod-copy-girwak is then the name of the new pod created for you, and it will
by default run
sleep infinity as the starting command, meaning it will keep
running forever until it’s deleted.
At this point you can enter the pod and run commands as you’d like, for
instance start a shell inside the pod with:
$ kubectl exec -it pod-copy-girwak -- bash root@pod-copy-girwak:/#
When you are done you can remove the copied pod again with
$ kubectl delete pod pod-copy-girwak pod "pod-copy-girwak" deleted
Say you instead would like to copy a pod, start a shell in the copied pod and
have the pod be deleted when you exit the shell, you can do that by supplying
--interactive flag like this:
$ copypod -p my-great-pod -i bash root@pod-copy-i41u04:/# ps -ef UID PID PPID C STIME TTY TIME CMD root 1 0 0 10:43 ? 00:00:00 sleep infinity root 7 0 0 10:43 ? 00:00:00 bash root 13 7 0 10:43 ? 00:00:00 ps -ef
When you are done doing what you needed the pod for, you can exit the shell and
the pod will be removed immediately.
The value for the
--interactive flag is the command you’d like to start
inside the pod.
Instead of having to look up the name of a pod before running
can also specify labels which match one or more pods that you’d like to copy.
copypod will then pick the first pod matching the lables and copy that for
you. This can be done with the
--selector flag. It works the same way as for
If we for example have one or more pods with the label
we can copy any of those pods without having to know the exact pod name by
$ copypod -l app=my-great-service -i bash root@pod-copy-1gk57f:/#
Note regarding Alpine Linux
sleep command in images based on Alpine Linux does not
support “infinity” as an argument unless the “coreutils” package is installed.
As a work around you can instead specify
--command "sleep 1d" as an argument
copypod to change the command run in the new pod.