[systemd-devel] Why is my reboot.target disabled?

[Andrei Borzenkov]

On 05.07.2023 11:57, Ferenc Wágner wrote:
> Andrei Borzenkov <arvidjaar at gmail.com> writes:
> 
>> On 04.07.2023 14:58, Ferenc Wágner wrote:
>>
>>> Please help me understand this phenomenon (systemd 252):
>>>
>>> $ systemctl status ctrl-alt-del.target
>>> ○ reboot.target - System Reboot
>>>        Loaded: loaded (/lib/systemd/system/reboot.target; disabled; preset: enabled)
>>>        Active: inactive (dead)
>>>          Docs: man:systemd.special(7)
>>>
>>> $ ls -l /{etc,run}/systemd/system | fgrep reboot
>>>
>>> $ ls -l /lib/systemd/system | fgrep reboot
>>> lrwxrwxrwx 1 root root   13 febr  28 12.15 ctrl-alt-del.target -> reboot.target
>>> -rw-r--r-- 1 root root  443 febr   1 18.20 plymouth-reboot.service
>>> -rw-r--r-- 1 root root  598 febr  16 19.10 reboot.target
>>> drwxr-xr-x 2 root root 4096 ápr   22 22.15 reboot.target.wants
>>> lrwxrwxrwx 1 root root   13 febr  28 12.15 runlevel6.target -> reboot.target
>>> -rw-r--r-- 1 root root  568 febr  16 19.10 systemd-reboot.service
>>>
>>> What does it mean that reboot.target is disabled?
>>
>> It means links listed in [Install] section are not present.
> 
> $ systemctl cat reboot.target
> [...]
> [Install]
> Alias=ctrl-alt-del.target
> 
> and there is a /lib/systemd/system/ctrl-alt-del.target -> reboot.target
> symlink as show above.  Why doesn't it count?
> 

Technically link in /etc does not exist and enable/disable machinery was 
created to manage links in /etc. But what happens now is certainly 
inconsistent.

bor at bor-Latitude-E5450:~$ systemctl status ctrl-alt-del.target
○ reboot.target - System Reboot
      Loaded: loaded (/lib/systemd/system/reboot.target; disabled; 
vendor preset: enabled)
      Active: inactive (dead)
        Docs: man:systemd.special(7)
bor at bor-Latitude-E5450:~$ systemctl is-enabled ctrl-alt-del.target
alias
bor at bor-Latitude-E5450:~$ echo $?
0
bor at bor-Latitude-E5450:~$

I do not know if this is intentional or a bug.

>>> Maybe related: why does 90-systemd.preset enable reboot.target but
>>> disable poweroff.target (for example)?
>>
>> There can be just one link target for ctrl-alt-del and reboot is the
>> most logical one.
> 
> And it's actually there, isn't it?