Zabbix 7.4.5 System Availability Percentage (24h)

[SZ_CGT]

Hi All
and first of all thank you for reading and helping if possible.
I'm a newbie on zabbix, most of the configurations i have done are "next -> next-> next... done" ... simple wizards and zero custom templates
I monitor with agents2 all our servers in the company...

I would like to create a SLA or Report or page or what ever where I can see a list of servers (windows and linux) and % of System Availability (it could be a weekly report or a montly report or decide if I select and ask a range of days...)

something like

server1 System Availability 99%
server2 System Availability 99%
server3 System Availability 99%


I have tried to create triggers or items or templates and then the count in percent doesn't work... googling gemini... create service or SLA... but I'm not good enought

I'm sure that someone else already have done something like this... All Bosses ask "System Availability" and not UPTIME server... as I do a reboot and the counter starts again... but availability of the server in 1 month is 100% because I didn't do any reboot.... or 99.5% because I have done some patches.... this is what my boss wants

Thanks
Simone