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flexible netflow and CLI - part two

some time ago I’ve written a post about displaying live traffic that is going throught he router, and how it splits based on autonomous system (with some sorting capabilities built in), thanks to Flexible NetFlow. recently, Flexible NetFlow was extended to use NBAR capabilities, and with that we have new options to sort traffic by application.

with slightly modified flow record snippet, we can collect also the application name:

flow record FNF-RECORD
 match ipv4 source address ! we can do IPv6 here as well
 match ipv4 destination address
 collect counter bytes
 collect counter packets
 collect application name  ! we collect three counters now
                           ! including app information from NBAR

of course this flow record needs to be part of the flow monitor:

!
flow monitor FNF-MONITOR
 record FNF-RECORD
!
interface GigabitEthernet0/1
 ip flow monitor FNF-MONITOR input
 ip flow monitor FNF-MONITOR output
 ! interface will collect both ingress and egress traffic
!
interface GigabitEthernet0/3
 ip flow monitor FNF-MONITOR input
 ip flow monitor FNF-MONITOR output
!

thanks to such construct, we can see live applications and the traffic they generate in bytes and packets:

router# sh flow monitor FNF-MONITOR cache aggregate application name sort counter bytes
 ! first we sort by application and then by number of bytes
Processed 342 flows
Aggregated to 16 flows
Showing the top 16 flows

APP NAME                               flows       bytes        pkts
================================  ==========  ==========  ==========
nbar http                                  6    60698006       63836
nbar bittorrent                            1       58728         906
nbar icmp                                  8       57547         837
nbar pop3                                  2       51775         233
nbar dns                                 175       44989         299
nbar ssh                                   2       40216         254
nbar bgp                                  39       39177         634
nbar smtp                                  7       18724          78
nbar ipsec                                 2       11896         106
nbar sip                                   2        2728           4
nbar h323                                  2        2276          27
nbar ntp                                  10         760          10
nbar snmp                                  2         759          10
nbar secure-http                           2         133           2

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