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I do not have access to an Ubuntu system or chroot. I was hoping if someone could tell me if the Ubuntu wiki is accurate in saying:

For Quantal, merged /usr should be supported. On new systems installer should create {/bin, /lib, /sbin} symlinks into /usr.

StrongBad
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    See: https://unix.stackexchange.com/questions/5915/difference-between-bin-and-usr-bin – Terrance Nov 27 '17 at 21:44
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    The wiki page was a proposal for discussion, not a final roadmap. Regardless of whether it was implemented in Quantal (13.04), it is not implemented in 17.10 and is not planned for 18.04. – user535733 Nov 27 '17 at 21:45
  • @Terrance not exactly true anymore. As of Fedora 17 (=2012) they do exactly this. – Rinzwind Nov 27 '17 at 22:01
  • @user535733 I apparently got fooled by the shiny Ubuntu wiki. Compared to the Arch discussion, the Ubuntu page convinced me that the merge happened. – StrongBad Nov 27 '17 at 22:09
  • @Rinzwind You know, that is interesting. By reading through the Filesystem Hierarchy Standard pages it would make me think that Fedora wouldn't be FHS compliant then. – Terrance Nov 27 '17 at 22:21
  • @Terrance I think a motivator is that most distributions will not even boot into single user mode without mounting /usr from the initramfs. – StrongBad Nov 27 '17 at 22:29
  • FHS is a guideline though. We are LSB compliant (https://en.wikipedia.org/wiki/Linux_Standard_Base). LSB is based on POSIX, and SUS https://en.wikipedia.org/wiki/Single_UNIX_Specification – Rinzwind Nov 27 '17 at 22:30
  • Regardless of symlinks or not, if the link itself does not cross over hard drives this configuration would work fine once in recovery mode if it was a link or not. By default, fstab is not loaded when going into recovery mode so a symlink crossing hard drive lines would then fail and the files would not be loaded. – Terrance Nov 27 '17 at 22:40
  • @StrongBad Oh, I forgot to mention feel free to call me Sterrance. =) – Terrance Dec 24 '17 at 16:48

2 Answers2

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Yes. As of at least Ubuntu 20.04, new installs use symlinks (existing systems won't be modified).

$ lsb_release -ds
Ubuntu 20.04 LTS
$ ll / | grep -E "usr|bin|lib"
lrwxrwxrwx   1 root root     7 Apr 23 15:02 bin -> usr/bin/
lrwxrwxrwx   1 root root     7 Apr 23 15:02 lib -> usr/lib/
lrwxrwxrwx   1 root root     8 Apr 23 15:02 sbin -> usr/sbin/
drwxr-xr-x  11 root root  4096 Apr 23 15:05 usr/

Seems like an unannounced change: Why are /bin and /sbin now symlinks in Ubuntu 20.04?

Gertlex
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  • How is it possible they didn't mark it anywhere? I've upgraded from 19.10 and looks like it didn't change that (or maybe it failed to apply this change?) – morhook Jun 08 '20 at 20:21
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    Good point. Updating comment as this only applies to new installs. – Gertlex Jun 09 '20 at 21:24
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No.

$ ls -l /
total 2097260
drwxr-xr-x   2 root     root           4096 okt 28 11:46 bin

drwxr-xr-x  21 root     root           4096 okt 21 10:32 lib
drwxr-xr-x   2 root     root           4096 okt 18 20:32 lib64

drwxr-xr-x   2 root     root          12288 okt 28 11:46 sbin

You are looking at a proposal. Besides that: we follow Debian and unless they do not set this up we probably will not.

===

The link from Terrance is a little bit invalid: Fedora did this from release 17 (= 2012). See https://fedoraproject.org/wiki/Features/UsrMove on this. But Debian, Ubuntu never went for this setup.

Rinzwind
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