I think the service state is normal with those systemd initd wrapper services and then pihole-FTL is again a multiple fork via su > sh > pihole-FTL, what systemd is not seeing as main process anymore.
This can be also copied all as is and paste to the terminal, as the terminal is processing it line by line anyway. But if everything is working again, then it is obviously not required. When running those G_* commands, it should then tell you that those settings are present already and do nothing.
Just a note:
I've come across cases where installing the gamin package would fix this. IIRC, those were Ubuntu installations, though, so I don't know whether that would be applicable to DietPi.
It can be used by desktops like KDE, GNOME or Xfce to have their virtual file systems keep track of changes to files and directories.
While it hooks into the file manager of desktops, I guess on pure server systems it needs to be setup a little get this information (who/what changed/removed which file) in a fitting way.
But as alternative libfam0 can be used, and if it is installed already, it is kept, of course.
Since groovy 20.10, libfam0 has been removed as alternative dependency, obviously as reaction to this bug: https://packages.ubuntu.com/groovy/lighttpd EDIT: Ah in focal-updates and even bionic-updates already, since January this year. I think those update suites are present and installed on default Ubuntu systems, right?
lighttpd (1.4.45-1ubuntu3.18.04.1) bionic; urgency=medium
* d/control: Depend on libgamin to fix missing symbol errors (LP: #1453463)
* d/test/control: introduce regression test for libgamin/libfam
* d/test/libfam-libgamin-conflict-regression: check for libgamin/libfam conflict regressions
-- Athos Ribeiro <athos.ribeiro@canonical.com> Tue, 15 Jun 2021 11:44:25 -0300
So the guys on GitHub have a point that on Ubuntu, libgamin0 (not the frontend) should be added as dependency to in case replace libfam0. This means that any strict dependants on libfam0 would be removed as well, good that the installer does now apt-get calls with full output, so users are asked whether to proceed and have those removed, and can cancel in case there is an important package affected.~EDIT: Fixed in the meantime, as of above Ubuntu changelog.
libfam0 is the preferred dependency, libgamin0 the alternative, so obviously the Lighttpd <> FAM incompatibility does not exist on Debian. One of the rare cases where package sources seem to differ, not for the good in case of Ubuntu.
Buttom line is that gamin is not a direct solution for a moved lighttpd.conf, but coincidentally its fontend could have helped to track who/what (re)moved it in the first place .
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