Zabbix 5.2 Does net.tcp.port work as documented?

[kwoot]

Hi,

The doc for net.tcp.port says: "Checks if it is possible to make TCP connection to specified port. Returns 0 - cannot connect; 1 - can connect"

When I do net.tcp.port[server.fqdn,80] to a firewalled port I would expect, per the documentation, a 0 return value after a timeout.
But it seems that I never get a return value for these tests because none show up in latest data.
Timeout is default.
Why is this not working?

Regards, Jeroen Baten

[kwoot]

Using net.tcp.service has the exact same result.

[cyber]

Does it work, if you try net.tcp.service() ? As you mention firewalls, it is possible to configure specific protocols in FW. Maybe FW drops your attempt silently?