10-15-2008
Because you are overriding the original file (redirection empties it). Destination should be some temporary file.
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LEARN ABOUT DEBIAN
flow-stat
flow-stat(1) General Commands Manual flow-stat(1)
NAME
flow-stat -- Generate reports with flow data.
SYNOPSIS
flow-stat [-hnpPw] [-d debug_level] [-f format] [-S sort_field] [-s sort_field] [-t tally_lines] [-T title]
DESCRIPTION
The flow-stat utility generates usage reports for flow data sets by IP address, IP address pairs, ports, packets, bytes, interfaces, next
hops, autonomous systems, ToS bits, exporters, and tags.
OPTIONS
-d debug_level
Enable debugging.
-f format
Report format. Choose from the following:
0 Overall Summary
1 Average packet size distribution
2 Packets per flow distribution
3 Octets per flow distribution
4 Bandwidth per flow distribution
5 UDP/TCP destination port
6 UDP/TCP source port
7 UDP/TCP port
8 Destination IP
9 Source IP
10 Source/Destination IP
11 Source or Destination IP
12 IP protocol
13 octets for flow duration plot data
14 packets for flow duration plot data
15 short summary
16 IP Next Hop
17 Input interface
18 Output interface
19 Source AS
20 Destination AS
21 Source/Destination AS
22 IP ToS
23 Input/Output Interface
24 Source Prefix
25 Destination Prefix
26 Source/Destination Prefix
27 Exporter IP
28 Engine Id
29 Engine Type
30 Source Tag
31 Destination Tag
32 Source/Destination Tag
-h Display help.
-n Use symbolic names where appropriate.
-p Display header information.
-P Report as percent total.
-s sort_field
Sort ascending on field sort_field.
-S sort_field
Sort descending on field sort_field.
-t tally_lines
Tally totals every tally_lineslines.
-T title Set report title to title.
-w Wide output.
EXAMPLES
Provide a report on top source/destination IP pairs sorted by octets, report in percent total form for the flows in /flows/krc4. Use the
preload option to flow-cat to preserve meta information and display it with flow-stat.
flow-cat -p /flows/krc4 | flow-stat -f10 -P -p -S4
EXAMPLES
Many times a campus network will have a single border router which has one interface pointing to the internal side and many interfaces
pointing to other providers. These interfaces each have a unique numerical id known in SNMP terms as an ifIndex. The ifIndex to interface
name mappings can be determined by using a tool such as snmpwalk or using show commands in recent versions of IOS with the 'show snmp mib
ifmib ifindex' or JunOS 'show interfaces'. Once the ifIndex for each interface is known flow-filter can be combined with flow-stat to pro-
vide reports such as inbound vs outbound top src/destination IP addresses.
Provide a top source IP address report by outbound traffic, ie the top senders of traffic on the campus network. Assume the ifIndex of the
campus interface is 5.
flow-cat -p /flows/krc4 | flow-filter -i5 | flow-stat -f9 -P -p -S3
EXAMPLES
Provide a top destination IP address report by outbound traffic, ie the top sinks of traffic on the campus network. Assume the ifIndex of
the campus interface is 5.
flow-cat -p /flows/krc4 | flow-filter -I5 | flow-stat -f8 -P -p -S3
EXAMPLES
Provide a top source/destination AS report. Use symbolic names.
flow-cat -p /flows/krc4 | flow-stat -f20 -n -P -p -S4
BUGS
None known.
AUTHOR
Mark Fullmer maf@splintered.net
SEE ALSO
flow-tools(1)
flow-stat(1)