I’ve been diving into Kubernetes lately and I hit a bit of a snag that I can’t seem to wrap my head around. So, here’s the scoop: I’m trying to copy multiple files from a Kubernetes container to my local machine, and I want to do it using a wildcard pattern. I thought it would be a straightforward task, but here I am scratching my head.
Here’s the situation: I’ve got a pod running that has a bunch of config files in a specific directory. Let’s say the path is something like `/app/config/` and I want to grab all `.yml` files from that directory. I figured I could use the `kubectl cp` command, but when I attempt to use a wildcard like `*.yml`, it doesn’t seem to work the way I envisioned.
I tried running something like:
“`
kubectl cp mypod:/app/config/*.yml ./local-config/
“`
But all I get is an error about the file not being found. It’s a bit frustrating, especially because I’ve seen various examples online that suggest using wildcards is possible. What am I missing? Is there a different approach I should be taking here? Should I maybe loop through the files in the container first and then selectively copy them one by one?
Another thought I had was to write a small script inside the pod that tars up the files first, but that feels like overkill for what should be a simple operation, right? Has anyone else dealt with this before? What’s the best practice for copying multiple files using wildcards in Kubernetes? I’m eager to hear your experiences or any tips you might have that could help me through this. Thanks in advance for any guidance you can share!
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Hey, I totally get your frustration! It sounds like you’re running into a common issue with `kubectl cp`. The thing is, `kubectl cp` doesn’t support wildcards in the way you might expect, because it gets executed on the client machine, not inside the container.
To grab multiple files with a wildcard, you can’t just do `*.yml` in the `kubectl cp` command. Instead, you’ll have to list the files another way. Here are a couple of approaches you could take:
You could run a command to list all `.yml` files and then copy them one by one. For instance, you can run something like this:
If you’re okay with a little bit of extra work, you can create a tar file of all your `.yml` files inside the pod and then copy that tarball to your local machine. Here’s how you do it:
If you have frequent needs to access multiple files, consider using a shared persistent volume or another temporary container that can serve the files.
So yeah, using a loop or a tar command would definitely be less of a hassle for your situation. It might feel a bit more complicated, but it’ll get the job done. Good luck!
“`
The issue you’re experiencing stems from how the `kubectl cp` command interprets source paths. The `kubectl cp` command does not support wildcard characters when specifying files within a container. When using wildcards, the command tries to interpret them as literal paths, thus resulting in the “file not found” error. To effectively copy multiple files matching a specific pattern, one common workaround is to use a two-step approach. First, you can execute a command inside the container to list the files you want to copy, which could be done using `kubectl exec`. For instance, you could run:
This way, you can manually check which files you intend to copy. After identifying the files, you can use separate `kubectl cp` commands for each file:
Another efficient method is indeed to create a tarball of the specific files you need. You can execute a command within the pod to create a tar file of all .yml files in the directory. Here’s a simple command you could run:
After you’ve created the tarball, you can use:
And finally, extract it in your local directory. This method may seem like overkill, but it’s efficient especially when dealing with a large number of files, and it’s definitely a best practice for bulk file operations in Kubernetes.