<div dir="ltr"><div dir="ltr">On Wed, Jun 16, 2021 at 10:43 AM Lennart Poettering <<a href="mailto:lennart@poettering.net">lennart@poettering.net</a>> wrote:<br></div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">On Di, 15.06.21 02:03, Kenneth Porter (<a href="mailto:shiva@sewingwitch.com" target="_blank">shiva@sewingwitch.com</a>) wrote:<br>
<br>
> What happens if I list multiple services in a Wants= and After= clause that<br>
> are mutually exclusive (eg. sendmail/postfix/exim? How can I say "This unit<br>
> needs to send mail" without knowing which is enabled?<br>
<br>
What does "needs to send mail" even mean? That /usr/sbin/sendmail can<br>
be called to queue a message? That you can talk to localhost:25?<br>
<br>
A well behaving MTA actually make /usr/sbin/sendmail work without the<br>
main mail daemon to be up. The mail is then only enqueued, but not<br>
dispatched, but that'll be done once the service is fully up.<br></blockquote><div><br></div><div>Hmm, I was going to post the same at first, but it doesn't really work in reverse -- if you want to send mail on shutdown and if the goal of After=postfix is "run my ExecStop before postfix gets stopped", then ability to queue doesn't help all that much.</div></div><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr">Mantas Mikulėnas</div></div></div>