Once upon a time, Peter Duffy <peter at pwduffy.org.uk> said: > The thing which always gets me about systemd is not the thing itself, > but the way it was rolled out. When I first installed Red Hat 7, if a > window had appeared telling me about systemd and asking me if I wanted > to use it, or stick with the old init framework, I'd have opted for the > latter (as I was interested primarily in continuity from the previous > version.) That's not really practical for something as core as the init system. Trying to support two init systems in parallel, especially for as long as Red Hat supports a RHEL release, would require a massive amount of work. A distribution is about making choices and implementing them in the best way possible; for "leaf" packages like an editor or a web browser, it is easy to have multiple options (where they don't conflict), but core stuff like the kernel and init system don't leave lots of room for choice. I remember people complaining about SysV-style init too, "what's with all these scripts" and "why can't I just add a line to /etc/rc". systemd is a different way of thinking, but it isn't exactly original (Sun and Mac have similar launchers); practical experience has shown that this can be a better way of managing services. daemontools has been around forever, haphazardly implemented for some things; now that behavior is where it makes the most since (PID 1 is guaranteed to get the signal). systemd makes implementing one-off services much easier, makes local modifications of service startup better (include another service and add the line you need), etc. One note: when I talk about systemd, I mean systemd-the-init-service that runs as PID 1. I'm not a big fan of systemd-the-project, that seems to have unlimited scope creep and reimplements every wheel in sight (years of work on NetworkManager, decades of work on NTP? we can do better!). Nobody is forcing you to run systemd; you can continue to run CentOS 6 and earlier for years. But if you are a system administrator, your job is about learning and adapting, not trying to keep a static setup for life. systemd is different (just like SELinux was years ago), but I suggest you learn it. It can make your admin life easier. Is it perfect? No, nothing ever is; I do think it is a big improvement though. -- Chris Adams <linux at cmadams.net>