Thanks to anyone, who gave this question some of his time. After writing the question, I remembered that I have changed the DNS in my router, so I checked which dns is being used by my machine:
and found that it is the one defined in my router, I changed it with 126.96.36.199 and now it's working as expected.
Are you using iwctl as instructed by the Installation Guide on the Arch-Linux wiki? It's generally not recommended to use videos when installing Arch, as Arch's base is typically updated monthly and this can result in changes to the installation process.
For a little more clarification why you need to review this, setting wlan0 to "up&...
As stated in the comments - your problem is most likely related to SElinux on RHEL8.
My solution was to circumvent SElinux with sudo as such:
$ grep ^zabbix /etc/sudoers
zabbix ALL=NOPASSWD:/usr/sbin/hddtemp, /usr/sbin/smartctl, /usr/bin/fping
and call the fping with sudo in front. Same goes for smartctl amd hddtemp
I think you are mixing up some things. The nmap always works because you are scanning the /24 network, which is different than the mDNS resolution.
The question is the PI getting different IP's via wifi? If so maybe that's the problem.
The super easiest solution is to just static IP the PI and stick it's address in you hosts file.
Or do you want to see why ...