I would look into something like Doppler instead of Vault. (I don’t trust any company acquired by IBM. They have been aquiring and enshittifying companies before there was even a name for it.)

Look into how any different solutions need their keys presented. Dumping the creds in ENV is generally fine since the keys will need to be stored and used somehow. You might need a dedicated user account to manage keys in its home folder.

This is actually a host security problem, not generally a key storage problem per se. Regardless of how you have a vault setup, my approach here is to create a single host that acts as a gateway for the rest of the credentials. (This applies to if keys are stored in “the cloud” or in a local database somewhere.)

Since you are going to using a Pi, you should focus on that being a restricted host: Only run your chosen vault solution on it. Period. Secure and patch it to the best of your ability and use very specific host firewall rules for minimum connectivity. Ie: Have one user for ssh in and limit another user account to managing vault, preferably without needing any kind of elevated access. This is actually a perfect use case for SELinux since you can put in some decent restrictions on the host for a single app (and it’s supporting apps…)

If you are paranoid enough to run a HIDS, you can turn on all the events for any type of root account actions. In theory once the host is configured, you shouldn’t need root again until you start performing patches.

That’s what you just got shown: Shove the configgy bits into Git.

You will likely have to find the configs you want to save first.

setenforce 0 is much cleaner, I have found.

Its just complex

When a security mechanism becomes more complex to manage than what it is supposed to protect, it becomes a vulnerability itself.

If you had a minimal system that you built from the ground up yourself and wanted to only have that system function in very specific ways, SELinix would be perfect. I would go so far as to say it would be nearing perfection in some ways.

Sorry, but in the real world, ain’t nobody got time for that shit. If you use auto configuration tools or pre-canned configs for SELinux on a system you are unfamiliar with, it’s more likely to cause application issues, create security gaps and will likely be shut off by a Jr. admin who really has no fucking clue what he is doing anyway.

It’s just easier to keep your system patched and ensure basic network security practices anyway.

It’s not impossible to manage these days. In the early days it was, but most everything is automagic now. If I am not mistaken, SELinux can be enabled to log only which would give you data better handled by a HIPS anyway. (Don’t quote me on that.)