Cisco Systems WSC4500X16SFP Manual De Usuario
38-2
Software Configuration Guide—Release 12.2(25)SG
OL-7659-03
Chapter 38 Configuring NetFlow
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.
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.
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).
fields contain a zero (0).
The following tables describe the supported fields for NDE version 5:
•
—Version 5 header format
•
—Version 5 flow record format
Table 38-1 NDE Version 5 Header Format
Bytes
Content
Description
0–1
version
NetFlow export format version number
2–3
count
Number of flows exported in this packet (1–30)
4–7
SysUptime
Current time in milliseconds since router booted
8–11
unix_secs
Current seconds since 0000 UTC 1970
12–15
unix_nsecs
Residual nanoseconds since 0000 UTC 1970
16–19
flow_sequence
Sequence counter of total flows seen
20–21
engine_type
Type of flow switching engine
21–23
engine_id
Slot number of the flow switching engine