<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Mon, Dec 11, 2017 at 10:14 PM, Boyce, Kevin P [US] (AS) <span dir="ltr"><<a href="mailto:Kevin.Boyce@ngc.com" target="_blank">Kevin.Boyce@ngc.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
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<p class="MsoNormal">Good Afternoon List,<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">I have a question regarding the use of systemd. I would like to know if it is possible to have two instances of system running at a time?<u></u><u></u></p>
<p class="MsoNormal"><u></u> <u></u></p>
<p class="MsoNormal">For instance I have an application that has a very complicated set of startup procedures. It runs on linux. I was considering using an instance of systemd with some custom unit files and targets as a self-contained startup procedure.
I was wondering if systemd could then start this systemd instance using an alternate root directory?</p></div></div></blockquote><div><br></div><div>Your description sounds almost exactly like what containers (systemd-nspawn, LXC, Docker) are normally used for – including both the nested init system and the alternate root directory. Systemd should work just fine when used as a container init process.</div><div><br></div><div>But beyond that, systemd only supports *one* "system mode" instance per system – that is, PID 1.</div><div><br></div><div>(It *does* support unprivileged "user mode" instances of `systemd --user`, limited to one per UID, but I'm not sure if these are suitable for "complicated startup procedures" in your case.)</div></div><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr">Mantas Mikulėnas <<a href="mailto:grawity@gmail.com" target="_blank">grawity@gmail.com</a>></div></div>
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