Why does kubectl cp command terminates with exit code 126?

Question

I am trying to copy files from the pod to local using following command:

kubectl cp /namespace/pod_name:/path/in/pod /path/in/local

But the command terminates with exit code 126 and copy doesn't take place.

Similarly while trying from local to pod using following command:

kubectl cp /path/in/local /namespace/pod_name:/path/in/pod

It throws the following error:

OCI runtime exec failed: exec failed: container_linux.go:367: starting container process caused: exec: "tar": executable file not found in $PATH: unknown

Please help through this.

score 26 · Answer 1 · answered Apr 14 '21 at 08:32

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kubectl cp is actually a very small wrapper around kubectl exec whatever tar c | tar x. A side effect of this is that you need a working tar executable in the target container, which you do not appear to have.

In general kubectl cp is best avoided, it's usually only good for weird debugging stuff.

answered Apr 14 '21 at 08:32

coderanger

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Nice! So at least we can `kubectl exec whatever cat c > x` or `kubectl exec whatever base64 c | base64 --decode > x` – Sassa NF May 14 '21 at 10:04

score 14 · Answer 2 · answered Apr 14 '21 at 08:34

14

kubectl cp requires the tar to be present in your container, as the help says:

!!!Important Note!!! Requires that the 'tar' binary is present in your container image. If 'tar' is not present, 'kubectl cp' will fail.

Make sure your container contains the tar binary in its $PATH

answered Apr 14 '21 at 08:34

chresse

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this was the solution for me! TYVM! – xero Aug 11 '21 at 18:38

score 14 · Answer 3 · edited Oct 10 '21 at 13:16

14

An alternative way to copy a file from local filesystem into a container:

cat [local file path] | kubectl exec -i -n [namespace] [pod] -c [container] "--" sh -c "cat > [remote file path]"

edited Oct 10 '21 at 13:16

RiveN

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answered Oct 10 '21 at 08:37

Yoni Sade

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So, the [remote file path] is suppossed to be is a directory or a complete filename? – Dhannanjai Jan 20 '22 at 13:05
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[remote file path] must include a filename as "cat" command expects to. – Yoni Sade Jan 21 '22 at 14:10
If the container doesn't have `cat`, will this approach to work?? – Enrique S. Filiage Jun 24 '22 at 19:09
No, but why wouldn't it have `cat`? – Yoni Sade Jun 25 '22 at 20:06

score 11 · Answer 4 · answered Feb 24 '22 at 06:49

11

Useful command to copy the file from pod to local

kubectl exec -n <namespace> <pod> -- cat <filename with path>  > <filename>

answered Feb 24 '22 at 06:49

Dinesh Verma

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very nice workaround – tryingToLearn Sep 20 '22 at 11:49

score 1 · Answer 5 · answered Jun 20 '22 at 10:31

For me the cat worked like this:

cat <file name> | kubectl exec -i <pod-id> -- sh -c "cat > <filename>"

Example:

cat file.json | kubectl exec -i server-77b7976cc7-x25s8 -- sh -c "cat > /tmp/file.json"

Didn't need to specify namespace since I run the command from a specific project, and since we have one container, didn't need to specify it

Why does kubectl cp command terminates with exit code 126?

5 Answers5