Slashdot Mirror
Ask Slashdot: Practical Alternatives To Systemd?
First time accepted submitter systemDead (3645325) writes "I looked mostly with disinterest at Debian's decision last February to switch to
systemd as the default init system for their future operating system releases. The Debian GNU/Linux distribution is, after all, famous for allowing users greater freedom to choose what system components they want to install. This appeared to be the case with the init system, given the presence of packages such as sysvinit-core, upstart, and even openrc as alternatives to systemd.
Unfortunately, while still theoretically possible, installing an alternative init system means doing without a number of useful, even essential system programs. By design, systemd appears to be a full-blown everything-including-the-kitchen-sink solution to the relatively simple problem of starting up a Unix-like system. Systemd, for example, is a hard-coded dependency for installing Network Manager, probably the most user-friendly way for a desktop Linux system to connect to a wireless or wired network. Just this week, I woke up to find out that systemd had become a dependency for running PolicyKit, the suite of programs responsible for user privileges and permissions in a typical Linux desktop.
I was able to replace Network Manager with connman, a lightweight program originally developed for mobile devices. But with systemd infecting even the PolicyKit framework, I find myself faced with a dilemma. Should I just let systemd take over my entire system, or should I retreat to my old terminal-based computing in the hope that the horde of the systemDead don't take over the Linux kernel itself?
What are your plans for working with or working around systemd? Are there any mainstream GNU/Linux distros that haven't adopted and have no plans of migrating to systemd? Or is migrating to one of the bigger BSD systems the better and more future-proof solution?"
Unfortunately, while still theoretically possible, installing an alternative init system means doing without a number of useful, even essential system programs. By design, systemd appears to be a full-blown everything-including-the-kitchen-sink solution to the relatively simple problem of starting up a Unix-like system. Systemd, for example, is a hard-coded dependency for installing Network Manager, probably the most user-friendly way for a desktop Linux system to connect to a wireless or wired network. Just this week, I woke up to find out that systemd had become a dependency for running PolicyKit, the suite of programs responsible for user privileges and permissions in a typical Linux desktop.
I was able to replace Network Manager with connman, a lightweight program originally developed for mobile devices. But with systemd infecting even the PolicyKit framework, I find myself faced with a dilemma. Should I just let systemd take over my entire system, or should I retreat to my old terminal-based computing in the hope that the horde of the systemDead don't take over the Linux kernel itself?
What are your plans for working with or working around systemd? Are there any mainstream GNU/Linux distros that haven't adopted and have no plans of migrating to systemd? Or is migrating to one of the bigger BSD systems the better and more future-proof solution?"
And now I use NetBSD.
systemd also has its own NetworkManager wanna be in the making as well. I also dislike this.
For shameless plug I currently maintain dhcpcd which does your DHCP, IPv4LL, IPv6RS and DHCPv6. Other nicities like carrier detection, SSID and ARP profiles, routing preferences all come as standard. All in 155k. For kicks there is even a basic GTK+ system tray notification widget that also talks to wpa supplicant to allow wireless network selection and password entry.
Slackware is an alternative mainstream Linux distribution which does not use systemd. Instead of systemd, it uses a combination of custom rc scripts and sysvinit. If Slackware ever adopts systemd as the default system init, they would likely lose most of their user base.
Solaris has it's own abomination called SMF. Good luck debugging network problems on Solaris without a GUI unless you're experienced with SMF. I use Solaris only to maintain my open source projects (I value portable code), and I _hate_ dealing with the system. So convoluted.
The system with the most straightforward configuration and init system, IMO, is OpenBSD. It's soooooooo nice. The only major change in nearly 15 years has been the move to an rc.d/ (init.d-style) startup script directory. Contrast that with number of convoluted changes in Linux administration over those past 15 years, and it seems like a miracle.
If SMF and launchd (OS X) are any indicator, I'm definitely going to hate working with systemd.
(NOTE: I haven't used Slackware since the 1990s, so maybe it's remained stable all these years, too. For Linux I tend to only use Debian and Ubuntu.)
The configuration system for daemons that systemd has is an enormous leap forward over the old shell scripts. If systemd would stick to be an init system, it would not be such a problem.
When it takes over file system mounting, including hiding most mount points from /etc/fstab and breaking silently if there are perfectly valid mounts in there which it happens not to like, people complain.
When it takes over system logging, previously one of the major advantages of Unix-based systems over Windows, people complain.
And so on and so forth.
Finally! A year of moderation! Ready for 2019?
Those interested may look at LWN's report for a saner, more balanced view: http://lwn.net/Articles/593676/
What's wrong with it? Here's my starting list and I'm sure I'll think of more....
- Binary Logs: Sorry, but there is no advantage to not being able to easily look at a log file.
- Failure to Log to the Console: There is nothing more frustrating than watching 5 screens of "Failed, use journalctl to blah, blah, blah..." come by when you know that your root filesystem isn't mounted read/write. There went *ALL* your debug information.
- Failure to Drop to a Shell When It Breaks: If my boot is broken,I want a shell. Not a hang. There's a way to force it to go to a shell, but that's before it does *anything* so you don't get to debug the failure, you get to guess what the failure might be and see if you can debug *that*.
- No way to see WTF it's doing: There's supposedly a command to make it tell you what order (and presumably what'll happen in parallel) things are going to start in. However, if you use that command as root, it tells you not to run it as root. If you do it as a normal user, it doesn't have permission to read all the files to tell you what it's doing.
- Races: I no longer have any idea what order things are starting in. I've had a cluster where everything worked fine. Until the a week and a few reboots later and then it occasionally failed. Don't even start to tell me that "I must have my dependencies wrong". I *KNOW* they're wrong. But I have no tools to help me figure out what "right" is. Plus, have you looked at how many unit files systemd starts on a normal system? I can't hold that much of a graph in my head. With SysV init, unless I turned on some weird parallel mode, everything starts in the same order every time.
- Complexity: I'm not a professional sysadmin. I'm a developer who has to maintain development systems (as well as personal systems) part time. If I worked with systemd every day, I'd probably be able to figure out ways to make it work for me. But I don't. SysV is just shell scripts. I *DO* deal with *those* every day so it's pretty easy to debug.
- Complexity, Part 2: The previous version of init essentially had no bugs. Ok, I'm sure that's not really true but they sure didn't surface very often. Since the results of your Process #1 dumping core are catastrophic (ie, a kernel panic), ideally that process should do as little as possible. That is *CLEARLY* not the design philosophy of systemd. Further, it consumes a decent amount of RAM and the more RAM you consume, the more likely (statistically) you are of hitting a memory error.
- YACL (Yet Another Config Language): Ok, so this is really a minor complaint but I get to learn yet another way of writing config files.
- Filesystems: SysV init tended to mount local filesystems *very* early in boot (some of that broke when udev got involved, but you could usually hack around that) and network filesystems not long after. I'm not entirely sure where systemd mounts filesystems, but it breaks *HORRIBLY* if you move some of the files needed by a service onto a filesystem that's not a "normal" filesystem. I'm sure there's some way to set all the dependencies to make that work, too, but see above, I have no f'ing way of figuring out what should depend on what.
From all outward appearances, the developers have *no* interest in fixing much of any of those complaints. The whole "debug on the kernel command line" fiasco is a pretty clear indication that they "don't play well with others". In the end, I'll see what Slackware has or maybe move (back) to the BSDs.
Go Badgers! -- #include "std/disclaimer.h"