What is this?

This knowledgebase contains questions and answers about PRTG Network Monitor and network monitoring in general.

Learn more

PRTG Network Monitor

Intuitive to Use. Easy to manage.
More than 500,000 users rely on Paessler PRTG every day. Find out how you can reduce cost, increase QoS and ease planning, as well.

Free Download

Top Tags

View all Tags

How to see ingress and egress bandwidth usage using Netflow



Hi ,

i am new to PRTG. I am configuring Netflow on all my branch routers. Branch routers are connected to HQ using MPLS. Below is the template i used on all routers. i am changing site specific infomation as required by each site.

router-2621(config)#ip flow-export destination 2250 
router-2621(config)#ip flow-export source FastEthernet 0/1 (This should be changed to relevant routers LAN interface name)
router-2621(config)#ip flow-export version 9
router-2621(config)#ip flow-cache timeout active 1
router-2621(config)#ip flow-cache timeout inactive 15
router-2621(config)#snmp-server ifindex persist
router-2621(config)#ip flow-top-talkers
router-2621(config)#top 10
router-2621(config-flow-top-talkers)#sort bytes
router#write mem

Interface Configuration mode

router-2621(config)#interface FastEthernet 0/1 (This should be changed to relevant routers LAN interface)
router-2621(config-if)#ip route-cache flow
router-2621(config-if)#ip flow ingress
router-2621(config-if)#ip flow egress 
router#write mem

My questions is i am using Netflow V9 standard sensor and it shows me bandwidth usage is only one traffic graph. I expecting to see 2 graphs one for ingress and other for egress. So the graph that it shown is it only showing one direction or total of both direction( ingress and egress) ?

Thanks, Sanka.

flow netflow prtg

Created on Jan 14, 2015 12:41:41 AM

Last change on Dec 2, 2021 8:26:21 AM by  Maike Guba [Paessler Support]

1 Reply




Thank you very much for using PRTG. The Netflow sensors do indeed not show Traffic In & Out as there is no exact relation for the "direction" in the packet data (seen in relation to an interface), as there is with SNMP where directly OctetsIN / OctetsOUT are read from the device.
You can achieve this though using Custom Netflow Sensors (with custom Channel Definitions).

best regards.

Created on Jan 15, 2015 4:01:37 PM by  Torsten Lindner [Paessler Support]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.