Relax, It's Just Ubuntu 15.04. AARGH IT'S FULL OF SYSTEMD | Hacker News Reader

Relax, It's Just Ubuntu 15.04. AARGH IT'S FULL OF SYSTEMD

theregister.co.uk

14 pointsbyaruhaf11 comments

I've actually gotten to the point where I don't mind systemd itself ("systemctl status" is a sysadmin's wet dream, and the built-in security and resource limit options are seriously wonderful), but what I do have a problem with is how the Linux ecosystem is turning into a monoculture.

IMO, Linux is at its healthiest when its two most popular server distributions, RHEL and Debian, are as different as they can possibly be. I really wish Debian would have gone with OpenRC for that reason.

built-in security and resource limit options are seriously wonderful

You could have used these already as separate tools that operate on process state. It's just kernel subsystems and syscalls at the end of the day. util-linux has them.

But with systemd, I can just throw an extra key-value pair in the unit file, and bam. No messing with wrapper programs, no modifying the service's code and recompiling, etc. It's not that it's not possible without systemd, it's that systemd makes it trivially easy.

It's either throw an extra key-value pair or throw an extra program name in front of the line to start. They're both trivially easy, and the latter has the advantage of being totally agnostic of anything other than the kernel.

When you boot Linux, the init system loads the drivers you need, turns on your network connection, fires up the necessary system service and then loads the desktop. Without an init system, you have no way to do anything.

Actually I'm pretty sure it's udev that handles module loading these days (which isn't related to the functions of init(8) and process management, even if it's part of systemd now), or alternately one can use the kmod tools manually.

This is a misleading interpretation in general. The init system (though really the process manager) starts the services to enable all these things. The simplest form is just a synchronous tool that exec()s binaries.

Yes, so what systemd did differently is to reify a lot more of the machinery so you can define a reaction graph for these synchronous events.

> This is a misleading interpretation in general. The init system (though really the process manager) starts the services to enable all these things. The simplest form is just a synchronous tool that exec()s binaries.

Even in traditional init systems, networking configuration is written into the init scripts themselves. For starting the desktop and udev, sure, the init script just starts a service, typically through start-stop-daemon, but the actual network configuration logic is in the init scripts.

> ...networking configuration is written into the init scripts themselves

This statement may technically be true, but it is misleading about what component actually does what.

It depends on where you consider the init system to end and the distribution's networking scripts to begin. On Debian and Ubuntu, the ifupdown package provides traditional networking configuration, and network-manager the "desktop roaming" networking configuration. They integrate with the init system like other services (and arguably a bit tighter) but they are still separate components.

So yes - as you say the networking configuration is written into the init scripts themselves, but the init scripts are provided by the distribution's networking components, not by the init system component.

And indeed the systemd switch in 15.04 - a replacement of init system - has happened but the networking configuration mechanism (ifupdown) remains. Both before and after the init system triggers the networking to be configured, but the init system is not the component that does the work.

I upgraded to 15.04. No real problems. In fact, systemd nicely addressed a few things that were really awkward for me before, and the integration with containers is very nice.

I suggest hanging out on AskUbuntu and trying to help people. It's far more informative than a sample of size 1.

There are various visible differences (http://askubuntu.com/a/613814/43344), and quite a lot of recurrent problems with outdated instructions from third parties (http://askubuntu.com/a/617822/43344), the "official" packages being behind the Ubuntu-supplied packages (http://askubuntu.com/a/617869/43344 http://askubuntu.com/a/617773/43344), assumptions of upstart breaking things (http://askubuntu.com/a/618138/43344 http://askubuntu.com/a/613785/43344), interactions with binary drivers (http://askubuntu.com/a/613773/43344), plexmediaserver (http://askubuntu.com/questions/601226/ http://askubuntu.com/questions/600026/ http://askubuntu.com/questions/617575/ http://askubuntu.com/questions/618275/), NetworkManager (http://askubuntu.com/questions/615006/), and X display manager logon (http://askubuntu.com/questions/614128/ http://askubuntu.com/questions/614013/).

Then there's the really popular "starting version 219" question (http://askubuntu.com/questions/618668/ http://askubuntu.com/questions/613776/ http://askubuntu.com/questions/617593/ http://askubuntu.com/questions/616426/ http://askubuntu.com/questions/613627/ http://askubuntu.com/questions/613969/).

Do you have a point? Of course there are problems rolling out a new, complicated system.

I've been using Linux since 1993. There is nothing new here, same process has been ongoing for 20+ years.

Reply on news.ycombinator.com