Monitor TCP port

[newteam]

Hello. It's my first post on this forum.
I'm trying to monitor if the RDP connection (tcp port 3389) of a server is running.
I found a template (<Template App Telnet Service>) that could be right and I cloned it.
I later changed the key to its item in:

<Net.tcp.service [telnet,, 3389]>

I left unchanged the expression of the trigger (I still can not understand it properly
-> the maximum value returned by the check in the last 3 seconds must be 0?):

<{Template App RDP Service: net.tcp.service [telnet ,, 3389] .max (# 3)} = 0>


However the check is performed regularly, but the result is always Down (0), despite the tcp 3389 port on the target server being regularly opened.
So I suppose there is a mistake in the expression.

Thanks for any info about it.

Regards

[ovas]

Hello newteam!

Take a closer look at your item type:
net.tcp.service[telnet,,3389]
The item is bound to check telnet service availability on the port 3389, it's logical that Zabbix cannot find it, because it's RDS service.

What you want to have a look at is net.tcp.port[<ip>,port] item type, where you specify both IP and port of RDS.

Generally, more information available online in Zabbix documentation, you should really stroll through it: https://www.zabbix.com/documentation/3.0/manual

[newteam]

Hi Ovas, thanks for the quick answer.
I am using Zabbix v_3.2 , and there is no key "net.tcp.port" in Symple check type. I also tried in the other checks type but the key seems to not exist.
I tried to insert manually the key net.tcp.port[,3389] but the response is "Unsupported item key".

Thanks

[ovas]

net.tcp.port is Zabbix agent check, you would require to install it on your Windows machine like that: https://www.zabbix.com/documentation.../windows_agent

[newteam]

Thanks !!! I found this check in Zabbix Agent:

net.tcp.listen[3389]

it works !

Thanks again.