I have Cisco N9K-C9396PX L3 switch which has VLAN interface configured for my LAN gateway and i want to monitor how much traffic vlanXXX handling, I have configured SNMP monitoring to pull interface traffic but VLAN interface always empty and blank

N9K# show interface vlan 200
Vlan200 is up, line protocol is up, autostate disabled
  Hardware is EtherSVI, address is  58f3.9ca9.d769
  Description: *** LAN ***  Internet Address is
  MTU 9216 bytes, BW 1000000 Kbit, DLY 10 usec,
   reliability 255/255, txload 255/255, rxload 255/255
  Encapsulation ARPA, loopback not set
  Keepalive not supported
  ARP type: ARPA
  Last clearing of "show interface" counters never
  L3 in Switched:
    ucast: 0 pkts, 0 bytes

I heard you can use counter command on interface but i found that command doesn't exist anymore on N9K

  • 3
    One problem with your idea is that traffic only passes through the layer-3 interface as it is entering or leaving the VLAN. Traffic that is sourced and destined on the same VLAN does not pass through the layer-3 interface, only from the source layer-2 interface to the destination layer-2 interface. Remember that layer-2 switching is done in hardware, and unicast frames are sent directly from interface-to-interface by the MAC address table. Only unknown unicast, broadcast, and [possibly] multicast frames would hit other interfaces. – Ron Maupin Nov 13 '19 at 14:41
  • Have you thought about Netflow? See "Configuring Bridged NetFlow on a VLAN: link – Pompi Nov 13 '19 at 19:01
  • show interface vlan 200 counters works with .9.3.1 on a n3k – Ricky Nov 14 '19 at 3:18
  • I ran that command but its has all counters are zero in output. – Satish Nov 14 '19 at 13:41

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.