Thanks for the well-argumented and informative response, appreciated.
> Your experience with SysV init seems to obscure its rougher edges to you. There's nothing obvious at all about SysV init in terms of the metadata-in-comments at the top of init scripts, run levels, rc.d, and the inconsistent suite of service-management utilities like update-rc.d and chkconfig. There's also the litany of executables invoked from within the init scripts like daemonize, start-stop-daemon, and runsv. Subtle errors in using these tools can open many security errors related to improper privilege dropping and inheriting too much of the admin's session.
You're right, with my 17-year experience, the internals and workarounds for particular flavors of SysV are very well known to me by now.
Actually, this is the core issue: systemd, as a complete replacement, makes all these years of experience obsolete and irrelevant. However, if we take commercial deployments, who is systemd's target audience? Existing sysadmins, who know SysV already.
If you force these people to learn something new, they would expect something intuitive and easy to understand based on their existing SysV experience. They would expect some "upgrade" based on the core SysV principles: they'd have to learn new things, but not start from scratch.
The way I see it, most of the new functionality could be implemented without a complete eradication of SysV concepts.
Unfortunately this is not the case and systemd designers preferred to throw out anything that reminds of SysV boot process. People like me simply don't understand why they have to spend hours learning new system when the old one wasn't "broken enough" for them. Once RHEL7 comes out, they'd just plainly reject it and look for a CentOS fork that keeps SysV in.
Small real-life example: About a year ago, I was given a Fedora laptop. I needed to configure it so that a specific application automatically starts on tty1 after booting (in order to show measurement results on screen). Unfortunately IT techs didn't heed to my advice to use older Fedora and I got a new one with systemd in. I planned to perform this configuration in 5-10 minutes, based on my existing knowledge, but it took me close to one hour and numerous searches on Google to figure out how to do it. Moreover, I had to touch like 3-4 config files in order to implement it.
I definitely didn't feel that systemd made it more easy for me to perform this task, I just felt that systemd makes my years of experience with SysV irrelevant and we should be careful not to install systemd on production systems, since at least due to lack of knowledge it'll take our sysadmins much longer to troubleshoot.
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