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--></style></head><body lang=EN-US link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Hello, I work for Amazon ECS and I’ve been working on a change to one of our systemd services. From what I could tell in documentation I found online, it seemed that RequiresOverridable= was the perfect fit for our use-case.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>When I built a package using this field, however, I got a message saying that this option is obsolete, which led me to this mailing list message: <a href="https://lists.freedesktop.org/archives/systemd-devel/2015-November/034880.html">https://lists.freedesktop.org/archives/systemd-devel/2015-November/034880.html</a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>So my question is, what would be the alternative to using RequiresOverridable? What got our attention to use this flag was that user input would be able to override the requirement, which is exactly what we want. Does Requires= also provide that capability? From our testing it _<i>seems</i>_ like it does but I don’t see it called out in the documentation anywhere.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>If it helps, I can describe our use-case below:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>We have a service that executes user-defined bash scripts on system startup called (simplifying) cloud-final.service.<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>We have a service called ecs.service that runs the ecs daemon service. This service’s configuration file is usually made by the user scripts run in cloud-final.service<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>3.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>So we wanted to make sure ecs.service starts after cloud-final.service. To accomplish this we put <a href="https://github.com/aws/amazon-ecs-init/blob/master/packaging/amazon-linux-ami/ecs.service#L20">After=cloud-final.service in ecs.service.</a><o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>4.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>But now we would also like users to be able to override ecs.service waiting for cloud-final.service to finish. Because cloud-final allows users to execute arbitrary bash scripts they should be able to run “systemctl start ecs” and the ecs service will start.<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>5.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>So the solution we were going to do was split ecs into two services:<o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l0 level2 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>a.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>ecs-ready.service which has After=cloud-final.service<o:p></o:p></p><p class=MsoListParagraph style='margin-left:1.0in;text-indent:-.25in;mso-list:l0 level2 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>b.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>ecs.service which has RequiresOverridable=ecs-ready.service<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>6.<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]>The idea above being that normally ecs.service would start with ecs-ready (and thus after cloud-final), but if the user explicitly requested it could be started without having to wait for after cloud-final.<o:p></o:p></p></div></body></html>