modified apache2.service overwritten on package update without notification

[sven]

Hi,

On my system I modified the apache2.service from:
 PrivateTmp=true
to:
 PrivateTmp=false

On 19/04/04 I updated my apache2 and the apache2.service was modified to:
  PrivateTmp=true

without notification.

Is it possible to prevent this behavior in the future?

Thank you and kind Regards,

Sven

-------------------------

Linux/Ubuntu:
Ubuntu 18.04.2 LTS
Linux XXXX 4.15.0-45-generic #48-Ubuntu SMP Tue Jan 29 16:28:13 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

Apache Version:
apache2/bionic-updates,bionic-security,now 2.4.29-1ubuntu4.6

File changed:
/lib/systemd/system/apache2.service

Expected:
Flawless Upgrade

What happened:
apache2.service was modified without notification, hence changing the system behaviour.

[Andreas Hasenack (ahasenack)]

You shouldn't modify the /lib/systemd/service/apache2.service file directly, but use an override instead.

For example, you can do "sudo systemctl edit apache2.service" and add your modifications in the editor that will open. This will create an override file in /etc/systemd/system/ for apache2, and a package upgrade won't change that.

"Example 2" at https://www.freedesktop.org/software/systemd/man/systemd.unit.html actually mentions your case, of setting PrivateTmp

I'll mark this bug as invalid, but if you think that's not the case, feel free to reopen it with a comment and reasoning.