Configuring Cisco Devices

     

    This section offers a brief guide to setting up NetFlow on a Cisco router or switch. For more detailed information, refer the Cisco web site at http://www.cisco.com/go/netflow. It is recommended that only people with experience in configuring Cisco devices follow these steps.

     

    Setting the appropriate time on the router

    NetFlow Analyzer stamps the flows based on the router time. It is therefore important to ensure that the time on the router is set properly. Netflow Analyer can handle routers from different time zones automatically, provided the correct time is set. 

    Whenever the time difference between the NetFlow Analyzer Server and the router is above 10 minutes a warning icon will appear in the home page. When this happens, NetFlow Analyzer will stamp the flows based on the system time of the NetFlow Analyzer server.

    In case you see this, please ensure the following on the router:

    • Check if the correct time is set on your router. You can check this by logging into the router and typing show clock. You can set the clock time using the command clock set hh:mm:ss date month year. [ An example : clock set 17:00:00 27 March 2007 ]
    • Check if the time zone and the offset (in Hours and Minutes) for the time zone is set properly (E.g. PST -8 00 for PST or EST -5 00 for EST). You can check this by logging into the router, going into the configure terminal and typing show running-config. You can set the clock time zone and offset using the command clock timezone zone hours [minutes]  (E.g. clock timezone PST -8 00)
    Tip To enable NetFlow in an MPLS environment refer Cisco's documentation on MPLS NetFlow