Can't get network traffic graphs

[emz]

Hello,

I manage Zabbix 2.4.6 server and I came across a problem with the servers that are pointed to it - when looking at the Zabbix graphs I can NOT see any statistics for the network traffic. It looks like there is no traffic at all and that is not true. The strange thing is that using the same templates and agent configs some other servers report that and I can see their network graph.
The problem is present for both virtual and physical Windows servers.



I have the following items configured:
net.if.in[{IPADDRESS}]
net.if.out[{IPADDRESS}]


Please help.

Edit:
Found something. When I set to monitor a host by its IP address instead of its hostname, the graphs is active:



However, that is not very suitable solution.

In the agents' log I see the following:

13248:20160226:074931.504 Requested [net.if.in[127.0.0.1]]
13248:20160226:074931.504 Sending back [0]

Is it possible that it is collecting statistics about the loopback interface? How can I avoid that?

[kloczek]

In the agents' log I see the following:

13248:20160226:074931.504 Requested [net.if.in[127.0.0.1]]
13248:20160226:074931.504 Sending back [0]

If agent is running on Unix first argument of net.if.{in,out} is not IP or address but network interface name.

https://www.zabbix.com/documentation/3.0/manual/config/items/itemtypes/zabbix_agent

net.if.in[if,<mode>]

if - network interface name (Unix); network interface full description or IPv4 address (Windows)