[systemd-devel] systemctl and detach in udev RUN

[Albert Strasheim]

Hello

On Thu, Oct 6, 2011 at 1:05 PM, Kay Sievers <kay.sievers at vrfy.org> wrote:
> On Thu, Oct 6, 2011 at 11:29, Albert Strasheim <fullung at gmail.com> wrote:
>> On Wed, Oct 5, 2011 at 4:10 PM, Albert Strasheim <fullung at gmail.com> wrote:
>>> Hello all
>>> I have the following udev rule in a machine with a bunch of disks:
>>> SUBSYSTEM=="block", KERNEL=="sd*", TAG+="systemd", ACTION=="add",
>>> RUN+="/bin/systemctl restart blockinit@%k.service"
>> To answer myself: systemctl has a --no-block option that seems like
>> the right thing to do here.
> It doesn't sound right, to call systemd from udev context. You might
> want to try if:
>  SYSTEMD_WANTS= (man systemd.device)
> works for you.

I've tried SYSTEMD_WANTS in the past, but it doesn't quite do what I want.

Usually when a device is re-added to the system, I want to restart the
associated service.

In some cases this might happen before the service itself has even
detected that its device has disappeared (example: rmmod your SAS
controller's module).

I'm also not quite sure how SYSTEMD_WANTS deals with failed services:
does it restart them if the device added again?

Regards

Albert