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PRTG can't differentiate between inbound traffic and outbound traffic when add manually sensor



I actually add a sensor manually. I chose Bandwith/Traffic, Windows and Packet Sniffing, the only issue now is that i can't distinguish between inbound traffic and outbound traffic, the graphics and the tables only show TOTAL values. I try in Edit and configuration off the sensor but it doesn't show an option for that... Is there anything that i could do to achieve that ? Maybe add a channel to the sensor or something like that ?

Best Regards Carlos

bandwidthsensor channel packet-sniffing sensor sensor-channel sensor-data traffic

Created on Jun 7, 2013 6:00:42 PM

3 Replies




thank you very much for your KB-Post. I'm very much afraid in that way, the Packet Sniffer does not directly differ between incoming and outgoing traffic (you could theoretically see this in the Toplists of the Sniffer Sensor though, by checking the source and destination IPs/Hostnames). Otherwise, you could also use a Windows Network Card Sensor for the same NIC. This one should give you Traffic In/Out (in addition to the details on the Packet Sniffer).

best regards.

Created on Jun 10, 2013 8:30:49 AM by  Torsten Lindner [Paessler Support]



Hi, Torsen, thank you for your answer... The thing is that at the beginnig PRTG doesn't see the NIC of the file server ( I don't know the reason, I just can't see the WMI Network Card sensor that appeared automatically for the other remote probes) , so I added a new sensor manually (chose Bandwith/ Traffic, Windows, packet sniffing) it shows total traffic, and now it let me chose the NIC, but it doesn't distinguish between inbound traffic and outbound traffic, the graphics and the tables only show TOTAL values. So I'm affraid that I will have to use that data. Is there maybe another option ?

I need to know the bandwith (Kbps) of my network that is used in the Intranet and Internet. I only have PRTG free version. So, for the traffic of the intranet I installed a PRTG server in a computer, and some remote probes, including one at the file server (Windows Server 2003), Second and more important question that I have it's about monitor the bandwith of Internet (in/out/total), I have firewall/proxy that connects to the ISP router, this proxy/firewall it's propietary and work under Linux. I tried to add a device to the local group, use the IP Adress of the Proxy/firewall and do autodiscovery there, It identifies the device but it only show sensors PING, HTTP1, etc, nothing about bandwith. I tried to add new sensor for the device but PRTG show a message that only can add sensors to probes. and when I tried to add sensor to local probe (PRTG server) SNMP shows me an error (I think SNMP isn't enable in the proxy/firewall, even I think it isn't enable any device of the network) so I tried packet sniffer but it isn't able, I tried Netflow but it doesn't show me any data. ( I don't know the reason either)

So I think that I could monitorize the port of the core switch (3Com 5500El) that conects to firewall/proxy, because I think all Internet traffic (in/out/total) passes trough this port. I tried to add new device (core switch) but the thing is that the core switch doesn't have IP address so I can't add it. I read about try to do mirroring port using and aditional computer that receives all the trafic in the NIC, but before these (because I'm not sure how to do this) What if I install a new PRTG server in the aditional computer, connect that directly to the core switch and run autodiscovery ? Will this show me the core switch ports (interfaces) and let me know the bandwith of them, specially of the port that is connected to the proxy/firewall ?

Could you help me, preferably without using SNMP ?

Best regards


Created on Jun 13, 2013 11:44:40 PM



You do not need to install another PRTG server. You can add the switch as a normal device in your existing PRTG and then add SNMP Traffic Sensors to it. Or manually add a WMI Network Card Sensor (not Packet Sniffing!) on this particular probe.

Created on Jun 14, 2013 7:33:55 AM by  Torsten Lindner [Paessler Support]

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