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su limitations and systemd

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go4linux
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Re: su limitations and systemd

#16 Post by go4linux »

dasein wrote:Okay, that's twice now...

Did I mistype a word? Misspell? Drop? (If so, I'm missing it, even on multiple readings.)

What you're attributing to me is exactly the opposite of what I wrote.

:?
can you be more specific?

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Head_on_a_Stick
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Re: su limitations and systemd

#17 Post by Head_on_a_Stick »

dasein wrote:I can't see any upside. At all.

Maybe someone can explain it.
Personally, I like the integration of `machinectl` with systemd-nspawn which will make it much simpler for me to set up and use Debian containers without messing around with debootstrap (or Docker).
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Wheelerof4te
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Re: su limitations and systemd

#18 Post by Wheelerof4te »

go4linux wrote:https://tlhp.cf/lennart-poettering-su/

Now looking at the bug report it seems that su does have problems. What I don't understand is why move it to systemd.
Is there some merit to it or it's time to move to FreeBSD?
No, no problems with ''su'' here. But systemd has broken my rig when i first did an upgrade of Wheezy->Jessie. I couldn't reboot or shutdown the computer, it just hanged there till I did hard poweroff.

So, yeah, when will this upgrade affect us currently on Jessie? So I can revert to Wheezy if it's gona be soon. Primary reason I switched to GNU/Linux was to get away from viruses that plagued my Winblows and to use a working, fast OS on an old Dell.

Off-topic: Nice to meet you all. I've been using Debian GNU/Linux for a while and have been visiting this forum to learn some things. This topic urged me to register and do what I can to support clean, non-bloated OS.

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Head_on_a_Stick
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Re: su limitations and systemd

#19 Post by Head_on_a_Stick »

Wheelerof4te wrote:So, yeah, when will this upgrade affect us currently on Jessie?
Never.

It has just been introduced with version 225 of systemd and jessie is "stuck" on version 215.
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Wheelerof4te
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Re: su limitations and systemd

#20 Post by Wheelerof4te »

^Thank you for a quick answer, that reassured me to stick with my Jessie :)

I knew that Debian stable versions don't upgrade packages, except security and major bug fixes, but I had fears that it may surprise us as ''proposed'' upgrade.

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Head_on_a_Stick
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Re: su limitations and systemd

#21 Post by Head_on_a_Stick »

^ Not to worry -- in my sid system, the machinectl & systemd-nspawn packages (and a few others) have been separated out from the main systemd package and have to be installed explicitly.

https://packages.debian.org/sid/systemd-container
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Randicus
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Re: su limitations and systemd

#22 Post by Randicus »

I was going to post the first reply in this thread last night, but while I was typing the internet went down. :evil: However, amazingly, my post is still relevant, so here it is.

:lol:
Long story short: su is really a broken concept.
This is from the same guy who says sysVinit is broken, Linux is broken, Windows is a superior design to Linux, and the BSDs are legacy systems.
go4linux wrote:What I don't understand is why move it to systemd.
Because everything will be part of systemd. You have not figured that out yet?

Randicus
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Re: su limitations and systemd

#23 Post by Randicus »

golinux wrote:Let's bring some balance to this thread:

https://lists.dyne.org/lurker/message/2 ... 9a.en.html
Personally, I think this this post by Laurent accurately describes the situation.
What he conveniently forgets, of course, is that having a
real root session with a separated environment, which is
what the new feature does, could already be achieved... by
logging in as root.

Duh!

So, this is just yet another propaganda stunt.
"su sucks. See? UNIX sucks! And now systemd can do so much
better than UNIX: it gives you real root sessions that do not
leak anything from the user environment."
"But, um, can't UNIX already do that ?..."
"NO NO NO systemd does it better because <insert confusing
buzzwords that will bamboozle executives and journalists>"

It's been like this since day 1 of systemd, and I'm not
expecting it to change any time soon.

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Danielsan
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Re: su limitations and systemd

#24 Post by Danielsan »

It seems that systemd is like a sort of cover to hide the real intention to put a closed kernel under GNU... It's just a distraction more efficient with a young arrogant in front line. I wasn't able to find any other reasons.

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keithpeter
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Re: su limitations and systemd

#25 Post by keithpeter »

Head_on_a_Stick wrote:^ Not to worry -- in my sid system, the machinectl & systemd-nspawn packages (and a few others) have been separated out from the main systemd package and have to be installed explicitly.
https://packages.debian.org/sid/systemd-container
Is that splitting out of the two packages from the main systemd distribution because Debian has the support for legacy sysv init based scripts? Will sid transition to a 'pure' systemd approach soon with no legacy or do I have to puggle with Fedora/rawhide to get the systemd as intended experience?

Would someone deploying containers have to use the machinectl shell command in the machinectl routinely?

Would the machinectl shell command be invoked programatically? The way you exit from machinectl shell (ctrl-J-J-J typed in one second) might get interesting for international keyboards given how a linux based system handles keyboard mapping (the termcap turtles &c).

(I am assuming that the su - command will remain for human users as it is a separate command so that the machinectl shell is an additional feature for the devops types, in which case we can all stop mumbling into our beards :twisted:)

go4linux
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Re: su limitations and systemd

#26 Post by go4linux »

https://lwn.net/Articles/572957/
Poettering began by noting that most people think of systemd as an init system, which it is, but that's just where it started and it is more than that now. Systemd is a set of "components needed to build up an operating system on top of the Linux kernel", he said. As part of the development of systemd, the team looked at various kernel features to see if they were relevant to the project.
FreeBSD is definitely starting to look more interesting

millpond
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Re: su limitations and systemd

#27 Post by millpond »

go4linux wrote:https://lwn.net/Articles/572957/
Poettering began by noting that most people think of systemd as an init system, which it is, but that's just where it started and it is more than that now. Systemd is a set of "components needed to build up an operating system on top of the Linux kernel", he said. As part of the development of systemd, the team looked at various kernel features to see if they were relevant to the project.
FreeBSD is definitely starting to look more interesting
Perhaps instead of forking debian we should fork systemd.
SYSTEMDFUL - an new and useFUL upgrade to Lennarts baby steps.
Its main purpose is to make sure it supplies proper LSBs to init scipts, and can be used as an extra way of turning on and off daemons. More the better. Perhaps control some even useFUL functions.
It can also check the hosts files for typos.
And no doubt an excellent weather display (in a tile) for Gnome3.

Randicus
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Re: su limitations and systemd

#28 Post by Randicus »

Ah hell. Go all the way. Let Poettering "fix" the kernel. :twisted:

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fireExit
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Re: su limitations and systemd

#29 Post by fireExit »

keithpeter wrote:The way you exit from machinectl shell (ctrl-J-J-J typed in one second)
it's not Ctrl-J(x3), it's Ctrl-] (square brackets three times)
But Ctrl-D (one time) also works)

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Head_on_a_Stick
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Re: su limitations and systemd

#30 Post by Head_on_a_Stick »

keithpeter wrote:Is that splitting out of the two packages from the main systemd distribution because Debian has the support for legacy sysv init based scripts?
Possibly, I hadn't thought of that.

I just presumed the developers did it to assuage the mass of conservative Debianees...
keithpeter wrote:Will sid transition to a 'pure' systemd approach soon with no legacy
I would really like that but I don't think so; Debian seems commited to being init-agnostic (cue flame attack from the tentacles people).
keithpeter wrote:Would someone deploying containers have to use the machinectl shell command in the machinectl routinely?
It is still possible to use systemd-nspawn (and other containers) without using `machinectl`, it's just a bit more of a faff.
keithpeter wrote:Would the machinectl shell command be invoked programatically? The way you exit from machinectl shell (ctrl-J-J-J typed in one second) might get interesting for international keyboards given how a linux based system handles keyboard mapping (the termcap turtles &c).
Good point, don't know about that but there must be a scriptable way of terminating the container -- I'll get back to you on this :)

EDIT: With systemd-nspawn, using `shutdown -p now` (or similar) closes the container.

EDIT2: Or use:

Code: Select all

machinectl terminate
keithpeter wrote:(I am assuming that the su - command will remain for human users as it is a separate command so that the machinectl shell is an additional feature for the devops types, in which case we can all stop mumbling into our beards :twisted:)
Yup :twisted:
Last edited by Head_on_a_Stick on 2015-08-31 20:11, edited 2 times in total.
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alansmithee
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Re: su limitations and systemd

#31 Post by alansmithee »

keithpeter wrote:(I am assuming that the su - command will remain for human users as it is a separate command so that the machinectl shell is an additional feature for the devops types, in which case we can all stop mumbling into our beards :twisted:)
The beard mumbling is not that someone implemented a new command that did something he wanted to do in a manner in which he wanted it done; it is his declaring any command that doesn't do what he wanted to do and/or not in a manner which he wanted it done must somehow be a "broken concept".
'alansmithee' is the user formerly known as 'saulgoode'.

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Danielsan
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Re: su limitations and systemd

#32 Post by Danielsan »

Why didn't they call it systemb(org)?

I think is more appropriate!

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buntunub
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Re: su limitations and systemd

#33 Post by buntunub »

At this point it is not about su being broken or not (it absolutely is not), but the monstrosity that is systemd gobbling every thing that is in userland and its eventual grab for the kernel as well until it is all part of Lennarts new OS called systemd. I really do not think anyone gives a sh#t if he does that so long as there is some way to revert the damage he is doing to linux as a whole with the dependancy problems. Since more and more upstream projects are now developing with/for systemd integration, that is becoming more and more remote.

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keithpeter
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Re: su limitations and systemd

#34 Post by keithpeter »

alansmithee wrote:
keithpeter wrote:(I am assuming that the su - command will remain for human users as it is a separate command so that the machinectl shell is an additional feature for the devops types, in which case we can all stop mumbling into our beards :twisted:)
The beard mumbling is not that someone implemented a new command that did something he wanted to do in a manner in which he wanted it done; it is his declaring any command that doesn't do what he wanted to do and/or not in a manner which he wanted it done must somehow be a "broken concept".
I accept your point. The gentleman's language is unfortunate sometimes, and some of his statements may come back to haunt him in the future. RHEL 7 is still in its early versions. Bulk deployment will start over the next few years. We shall see what new bugs crawl out as systems based on the newer versions of systemd enter large scale service. The acid test will be in how quickly they get fixed.

It appears the machinectl shell command isn't replacing the venerable su - but is in addition.

https://lists.debian.org/debian-user/20 ... 01290.html

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