Cisco 4500M Software Manual page 562

Overview of NetFlow Statistics Collection
NetFlow exports flow information in UDP datagrams in one of two formats. The version 1 format was
the initial released version, and version 5 is a later enhancement to add Border Gateway Protocol (BGP)
autonomous system (AS) information and flow sequence numbers. In version 1 and version 5 format, the
datagram consists of a header and one or more flow records. The first field of the header contains the
version number of the export datagram.
This section contains the following subsections:
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NDE Versions
The Catalyst 4500 series switch supports NDE versions 1 and 5 for the captured statistics. NetFlow
aggregation requires NDE version 8.
Depending on the current flow mask, some fields in the flow records might not have values. Unsupported
fields contain a zero (0).
The following tables describe the supported fields for NDE version 5:
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Table 40-1 NDE Version 5 Header Format
Bytes
0–1
2–3
4–7
8–11
12–15
16–19
20–21
21–23
Software Configuration Guide—Release 12.2(25)EW
40-2
Information Derived from Hardware, page 40-3
Information Derived from Hardware, page 40-3
Information Derived from Software, page 40-4
Determining the Input and Output Interface and AS Numbers, page 40-4
Feature Interaction of Netflow Statistics with UBRL and Microflow Policing, page 40-5
VLAN Statistics, page 40-5
Table 40-1—Version 5 header format
Table 40-2—Version 5 flow record format
Content
version
count
SysUptime
unix_secs
unix_nsecs
flow_sequence
engine_type
engine_id
Chapter 40
Description
NetFlow export format version number
Number of flows exported in this packet (1–30)
Current time in milliseconds since router booted
Current seconds since 0000 UTC 1970
Residual nanoseconds since 0000 UTC 1970
Sequence counter of total flows seen
Type of flow switching engine
Slot number of the flow switching engine
Configuring NetFlow Statistics Collection
OL-6696-01