NetFlow data flow only appears in the Ingress or Egress interface

After you install SolarWinds NetFlow Traffic Analyzer (NTA) and begin collecting your data, all or some devices show netflow data traveling in one direction: Into the device (Ingress) or out of the device (Egress). 

This issue occurs because the device configuration is missing some commands. These commands vary, based on whether your LAN or WAN interface uses Cisco^® IOS Flexible NetFlow technology. 

This issue can occur if you have a device with LAN and WAN interfaces with no WAN interface commands. 

This issue can also occur if you have a device with LAN and WAN interfaces and both interfaces include commands.

Update your device configurations, depending on whether your device uses WAN or LAN interface commands.  

Configure devices with LAN interface commands only

If you have a device with LAN and WAN interfaces with no WAN interface commands, perform the following steps:

1. Log in to the device.
2. Verify the interface configuration.
3. Add the appropriate commands to the LAN interface:
   1. If your interface does not use IOS Flexible NetFlow, add the following command: ip flow egress
   2. If your interface uses IOS Flexible NetFlow, add the following command: ip flow monitor NetFlow-Monitor input 
4. Ensure that the WAN interface does not include any commands. 

   Your configuration is completed. 

Configure devices with WAN and LAN interface commands

If you have a device with LAN and WAN interfaces and both interfaces include commands, perform the following steps:

1. Log into the device(s) in question.
2. Change the WAN interface configuration by deleting the current commands and adding new commands:
   1. If your interface does not use IOS Flexible NetFlow, add the following command: ipflow ingress
   2. If your interface uses IOS Flexible NetFlow, add the following command: ip flow monitor NetFlow-Monitor input
3. Do not edit the LAN interface configuration.

   Your configuration is completed. 

View network traffic data in both directions

You can configure your interfaces so that you can view network traffic data in both directions. Use the appropriate commands listed in the table below. For two or more interfaces, use the targeted command on each interface.