kpm - Kernel Parameter Manager

What is this?

kpm (as the name suggests) is a program to manage kernel parameters. It reads target values from the environment and sets them if they do not match.

Why does this exist?

To run as a DaemonSet on a Kubernetes cluster, to enforce a set of target kernel parameters.

How do I get this majestic tool?

sh $ cargo install kpm

How do I use it?

For each managed Kernel Parameter, set an environment variable to the target value. The name of this variable should be the parameter name, prefixed with sysctl-.

sh env sysctl-fs.inotify.max_queued_events=16384 \ sysctl-fs.inotify.max_user_instances=128 \ sysctl-fs.inotify.max_user_watches=8192 \ kpm enforce

By default, kpm only treats values that exactly match the target as "correct". This can be overridden by prefixing the value with one of the following identifiers:

| Prefix | Rule | Description | |--------|---------|--------------------------------------------------------| | == | EqualTo | Value must be exactly equal to the target. | => | AtLeast | Value must be greater than or equal to the target. | =< | AtMost | Value must be less than or equal to the target.

These do not work with non-integer parameters. Since the vast majority of kernel parameters are integers, this is unlikely to be a problem. Use with string parameters will report false negatives, and set the value every time.

Environment Variables

| Name | Default Value | Examples | Description | |----------------|---------------|----------------------------------|--------------------------| | KPMLOGFILTER | info | error, warn, info, debug, trace. | Configures log filtering | | KPMLOGSTYLE | auto | auto, always, never. | Configures log styling |

License

kpm is available under the MIT License, see LICENSE.txt for the full text.