[systemd-devel] when tmp.mount masked - root partition mounted read only

[Gena Makhomed]

Hello, All!

Rocky Linux 9.1, systemd 250 (250-12.el9_1.3)

After server installation and reboot - root partition mounted read only
when tmp.mount masked. Without any errors or warnings in any log files.

I spent many time to find root cause of this bug.

I try almost anything, but this message on github help me to understand
situation and make root filesystem mountable in the read/write mode:

https://github.com/systemd/systemd/issues/5358#issuecomment-322040808

Have same experience, in my case tmp.mount was masked and that
(silently!) stopped systemd-remount-fs.service from being executed.

=========================================

Recommendation to mask tmp.mount I found at the freedesktop.org:

https://www.freedesktop.org/wiki/Software/systemd/APIFileSystems/

Disable any mounting on /tmp so that it resides on the same physical 
file system as the root directory. For that, execute systemctl mask 
tmp.mount

=========================================

May be this is bug in the systemd code? Because I don't see any warnings
or errors I just see, what systemd-remount-fs.service in the dead state.

 From user point of view these two things are completely unrelated -
disabling any mounting /tmp and mounting root filesystem of server
in the read only mode.

Very confusing what I can't find any error messages in the logs
but can find in the systemd documentation very dangerous
recommendation to mask tmp.mount

May be it is possible fix this bug in systemd code
and systemd documentation on the freedesktop.org ?

-- 
Best regards,
  Gena