sysctl

Manages a kernel parameter (sysctl key): sets its runtime value and, by default, records it in a keystone-managed drop-in under /etc/sysctl.d/ so it survives a reboot. Idempotent: re-applying an unchanged declaration reports no change.

Category: System config

States

State	Meaning
`present`	The kernel parameter (the declaration name) has the declared `value`; with `persist: true` (the default) a drop-in under `/etc/sysctl.d/` also records it.

Parameters

Parameter	Type	Required	Description
`value`	string	yes	The value to set. Multi-field values (e.g. `"4096 16384 4194304"`) are whitespace-normalized; ints/bools are accepted and coerced to strings.
`persist`	bool		Write a `/etc/sysctl.d/` drop-in so the value survives reboot. Set `false` to change only the running value. Default: `true`.

Examples

Enable IPv4 forwarding (runtime + persisted)

sysctl:
  net.ipv4.ip_forward:
    state: present
    value: "1"

Set a runtime-only value

With persist: false only the running kernel value changes; no drop-in is written.

sysctl:
  net.core.somaxconn:
    state: present
    value: "1024"
    persist: false

Multi-field value (slashed key form)

Keys accept slashed notation; it is normalized to the dotted form.

sysctl:
  net/ipv4/tcp_rmem:
    state: present
    value: "4096 16384 4194304"

Notes

Linux only; BSD/macOS sysctl namespaces differ and are out of scope.
The declaration name is the kernel key, in dotted (net.ipv4.ip_forward) or slashed (net/ipv4/ip_forward) form — both normalize to the same persistence file.
One drop-in file per key; a single consolidated keystone drop-in is a future enhancement.
v0.1 sets the value directly and does not run sysctl --system, so no reload is needed this boot.

kernel_module timezone