Whether /etc/sysctl.conf will still take effect, if symbolic link /etc/sysctl.d/99-sysctl.conf is broken on without tuned.service system ?

Issue

• Whether /etc/sysctl.conf will still take effect, if symbolic link /etc/sysctl.d/99-sysctl.conf is broken on without tuned.service system ?

• Why RHEL7 still execute /etc/sysctl.conf even missing /etc/sysctl.d/99-sysctl.conf during system booting on without tuned.service system ?

- Remove of symbolic link.
1. set 'vm.nr_hugepages = 5' in /etc/sysctl.conf
2. remove symbolic link /etc/sysctl.d/99-sysctl.conf
3. reboot system and vm.nr_hugepages is still effective

- Delete /usr/lib/sysctl.d/99-sysctl.conf file.
1. set 'vm.nr_hugepages = 5' in /etc/sysctl.conf
2. delete /usr/lib/sysctl.d/99-sysctl.conf file
3. reboot system and vm.nr_hugepages is still effective

• Why RHEL8&RHEL9 doesn't execute /etc/sysctl.conf even missing /etc/sysctl.d/99-sysctl.conf during system booting on without tuned.service system ?

- Remove of symbolic link.
1. set 'vm.nr_hugepages = 5' in /etc/sysctl.conf
2. remove symbolic link /etc/sysctl.d/99-sysctl.conf
3. reboot system and vm.nr_hugepages is not effective

- Delete /usr/lib/sysctl.d/99-sysctl.conf file.
1. set 'vm.nr_hugepages = 5' in /etc/sysctl.conf
2. delete /usr/lib/sysctl.d/99-sysctl.conf file
3. reboot system and vm.nr_hugepages is not effective