Dear DevTeam,
I have seen a strange behaviour on a LXC container during my lab tests.
The Item key "system.uptime" show the "uptime" of the main host (HyperVisor...) and not the right one exposed on "/proc/uptime".
From my research could be related on where the Zabbix Agent collect this information, some other monitoring tool are looking on "/proc/stat" btime value. In this case on my system the value represent the "host uptime" and not the Container uptime.

[root@lab1 ~]# cat /proc/stat|grep btime
btime 1661878328

root@lab1 ~]# uptime
 10:57:58 up 5 days, 17:53,  2 users,  load average: 1.55, 1.87, 1.80

This behaviour could be fixed from Zabbix Agent side or is related to LXC?
Thanks