Cisco Network Function Virtualization Infrastructure Software Configuration Guide, Release 26.2 and Later

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Cisco Network Function Virtualization Infrastructure Software Configuration Guide, Release 26.2 and Later

Configure packet capture

Updated: June 29, 2026

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Configure packet capture to analyze all packets being transmitted and received over physical and virtual network interface controllers.

The Packet Capture feature helps you capture all packets being transmitted and received over physical and virtual network interface controllers (physical port and vNIC) for analysis. These packets are inspected to diagnose and solve network problems.

You can customize the configuration to capture specific packets such as Internet Control Message Protocol (ICMP), TCP, UDP, and Address Resolution Protocol (ARP).
You can specify a time period over which packets are captured. The default is 60 seconds.

Packets are stored in the /data/intdatastore/pktcaptures folder on the host server.

Procedure

Configure packet capture on a physical port.

Example:


configure terminal
tcpdump port eth0

Output: pcap-location /data/intdatastore/pktcaptures/tcpdump_eth0.pcap

Configure packet capture on a vNIC.

Example:


configure terminal
tcpdump vnic tenant-name admin deployment-name 1489084431 vm-name ROUTER vnic-id 0 time 30

Output: pcap-location /data/intdatastore/pktcaptures/1489084431_ROUTER_vnic0.pcap

Table 1. Types of errors
Error	Scenario
Port/vnic not found	When non-existing interface is given as input.
File/directory not created	When the system is running out of disk space.
The tcpdump command fails	When the system is running out of disk space.

These errors are logged in the nfvis_config.log. By default, warnings and errors are logged.

Packet capture is configured and packets are captured to the specified location for analysis.

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