Forum Discussion

Ryan_Watters's avatar
4 years ago

Flexible Netflow help

Flexible Netflow from Cisco seems overly complicated.  I was able to get Netflow going with my Palo Alto firewalls in about 5 minutes with LogicMonitor.  With my Cisco C3850 and 9300 switches, it's...
  • mnagel's avatar
    4 years ago

    Sure, I have developed internal docs on this which I exported to PDF, but of course this forum does not allow that.  Honestly, this is stuff that should be maintained in the LM documentation.  I will see if I can copy the details over to a blog post or something on our website.  In the meantime, here is the 3650/3850 section.  I believe the 9300 should be pretty similar, but I do have distinct notes for 9200 and 9500 switches.

    3650/3850

    This platform requires separate flow records for input and output.  To monitor traffic to/from the switch (e.g., for Internet flow reporting), the monitors below should be applied as input and output, respectively:

    interface GigabitEthernet2/0/11
     ip flow monitor LM-IN input
     ip flow monitor LM-OUT output
    flow exporter WM-LMW2
     destination 192.168.x.x
     transport udp 2055
     template data timeout 60
     option interface-table
     option exporter-stats
     export-protocol netflow-v9
    
    flow record Netflow-In
     match flow direction
     match interface input
     match ipv4 destination address
     match ipv4 protocol
     match ipv4 source address
     match ipv4 tos
     match transport destination-port
     match transport source-port
     collect counter bytes long
     collect counter packets long
     collect interface output
    
    flow record Netflow-Out
     match flow direction
     match interface output
     match ipv4 destination address
     match ipv4 protocol
     match ipv4 source address
     match ipv4 tos
     match transport destination-port
     match transport source-port
     collect counter bytes long
     collect counter packets long
     collect interface inputflow monitor LM-IN
     exporter WM-LMW2
     cache timeout inactive 10
     cache timeout active 60
     record Netflow-In
    
    flow monitor LM-OUT
     exporter WM-LMW2
     cache timeout inactive 10
     cache timeout active 60
     record Netflow-Out