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Manual Reference Pages  -  FLOW-TAG (1)


flow-tag - Apply tags to flow files.




flow-tag [ -hk ] [ -b big|little ] [ -C comment ] [ -d debug_level ] [ -t tag_fname ] [ -T tag_definition ] [ -v variable binding ]


The flow-tag utility is used to add or modify source and destination tags in flow records. Tags are 32 bit identifiers derived from rules and fields in a flow record. Tags can be used to group flows with common prefixes, autonomous systems, next hops, exporter id and/or input/output interface. flow-stat can be used with tagged flows to produce group based reports. For example, all outbound traffic for a customer where the customer is defined by a list of IP prefixes.


-b big|little
  Byte order of output.
-C Comment
  Add a comment.
-d debug_level
  Enable debugging.
-h Display help.
-k Keep time from input.
-t tag_fname
  Load tags from tag_name. Defaults to /usr/local/etc/flow-tools/tag
-T active_def|
  Use active_def as the active tag definition(s).
-v variable binding
  Set a variable FOO=bar.

The configuration file is a collection of actions and definitions. An action is triggered by a definition and a definition is invoked only if listed with the -T flag. Lines begining with # are treated as comments and ignored.

Words in the configuration file of the form @VAR or @{VAR:default} will be expanded at run-time by setting variable names with the -v option.

tag-action command            Description/Example
tag-action                    Begin tag-action section
                              tag-action foo

type Configure the type of action, one of source-prefix, destination-prefix, prefix, source-as, destination-as, as, next-hop, tcp-source-port, tcp-destination-port, tcp-port, udp-source-port, udp-destination-port, udp-port, tos, exporter, source-ip-address, destination-ip-address, ip-address, input-interface, output-interface, interface, any. type src-prefix

match Match criteria. The match condition depends on the type. Following the match condition is one of set-destination, set-source, or-destination, or-source to set or logically or a value to the source or destination tag. match 128.146/16 set-destination 0x010001

Multiple actions may match and set tags on the same flow. Note that listing many actions will cause tags to be applied in O(actions) time. The actions try to run in O(1) time. For example if 10 prefixes are listed in a single action it will take about the same CPU as if 100 prefixes are used. Listing 100 actions will require 100 times the CPU as 1 action.

tag-action types Description ----------------------------------------------------------------------

source-prefix Source Prefix

destination-prefix Destination Prefix

prefix Source or Destination Prefix

source-as Source AS

destination-as Destination AS

as Source or Destination AS

next-hop IP Next Hop

tcp-source-port TCP Source Port

tcp-destination-port TCP Destination Port

tcp-port TCP Source or Destination Port

udp-source-port UDP Source Port

udp-destination-port UDP Destination Port

udp-port UDP Source or Destination Port

tos Type of Service

exporter Exporter IP Address

source-ip-address Source IP Address

destination-ip-address Destination IP Address

ip-address Source or Destination IP Address

input-interface Input Interface

output-interface Output Interface

interface Input or Output Interface

any Match any flows

tag-action matches Description ----------------------------------------------------------------------

set-destination Set the destination tag, replacing any previous tag.

set-source Set the source tag, replacing any previous tag.

or-destination Logically or this value to the existing destination tag

or-source Logically or this value to the existing source tag

A definition lists a set of actions which are evaluated if the filter criteria is met. Each definition is built with terms. A term has its action(s) evaluated if the filter is passed.

definition command                  Description/Example
tag-definition                      Begin tag-defintion secrion
                                    tag-definition bar

term Begin a list of actions to be evaluated that match the filter rule. term

input-filter List of input ifIndexes the flow must match. input-filter 1,2,3,4

output-filter List of output ifIndexes the flow must match. output-filter 1,2,3,4

exporter IP address of exporter the flow must match. exporter

action Name of action to evaluate. Actions are evaluated in the order they appear in a definition. action foo


The meaning of a tag is user defined. The following example uses 16 bits of a tag as a customer ID and 4 bits as a customer type. flow-xlate can be used to apply a mask to these fields.

# file: gigapop-tags
# tag format
# 0       7         15        23        31
# 0000 0000 0000 0000 0000 0000 0000 0000 (32 bits)
#              |    |                   | Site name
#              |    | Site type
#              | Reserved
# SITE_TYPE_MASK = 0x00FF0000
# ID             Name
# 0x0001         OSU
# 0x0002         CWRU
# 0x0003         BGSU  
# ... etc
# 0x0019         MULTICAST
# ID             Type 
# 0x01         Participant
# 0x02         SEGP
# 0x03         Sponsored-Participant
# 0x04         Gigapop
# 0x05         MULTICAST

tag-action OHIO-GIGAPOP_DST type destination-prefix # OSU match 128.146/16 set-destination 0x010001 match 164.107/16 set-destination 0x010001 match 140.254/16 set-destination 0x010001 match 192.153.26/24 set-destination 0x010001 # CWRU match 129.22/16 set-destination 0x010002 match 192.5.110/24 set-destination 0x010002 # BGSU match 129.1/16 set-destination 0x010003 # ...etc # MULTICAST match 224/4 set-destination 0x050019

tag-action OHIO-GIGAPOP_SRC type source-prefix # OSU match 128.146/16 set-source 0x010001 match 164.107/16 set-source 0x010001 match 140.254/16 set-source 0x010001 match 192.153.26/24 set-source 0x010001 # CWRU match 129.22/16 set-source 0x010002 match 192.5.110/24 set-source 0x010002 # BGSU match 129.1/16 set-source 0x010003 # ...etc

tag-action OTHER_DST type destination-prefix match 0/0 set-destination 0x0

tag-action OTHER_SRC type source-prefix match 0/0 set-source 0x0

tag-definition OHIO-GIGAPOP term # Abilene interface input-filter 25 # clear tag first -- it defaults to 0, so this may not be necessary. action OTHER_DST action OHIO-GIGAPOP_DST term # Abilene interface output-filter 25 # clear tag first -- it defaults to 0, so this may not be necessary. action OTHER_SRC action OHIO-GIGAPOP_SRC

First populate /usr/local/etc/flow-tools/tag for flow-stat to use as symbols.

0x0001 OSU
0x0002 CWRU
0x0003 BGSU
0x010000 PART
0x020000 SEGP
0x030000 SPART
0x040000 GIGAPOP
0x050000 MULTICAST

To generate a report for outgoing traffic to Abilene based on customer ID:

flow-cat flows | flow-filter -I25 | flow-tag -t gigapop-tags -TOHIO-GIGAPOP | flow-xlate -t0x0000FFFF | flow-stat -n -f30 -S2

#  --- ---- ---- Report Information --- --- ---
# Fields:    Total
# Symbols:   Enabled
# Sorting:   Descending Field 2
# Name:      Source Tag
# Args:      ../flow-stat -n -f30 -S2
# Src Tag   flows                 octets                packets
OSU         4942230               181326237007          302476793
CWRU        874883                54358312807           70589318
BGSU        1008797               7600209852            22060870

To generate a report for inbound traffic from Abilene based on customer type:

flow-cat flows | flow-filter -i25 | flow-tag -t gigapop-tags -TOHIO-GIGAPOP | flow-xlate -T0xFF0000 | flow-stat -n -f31 -S2

#  --- ---- ---- Report Information --- --- ---
# Fields:    Total
# Symbols:   Enabled
# Sorting:   Descending Field 2
# Name:      Destination Tag
# Args:      ../flow-stat -n -f31 -S2
# Dst Tag   flows                 octets                packets
PART        15923156              663289954569          981163979
SEGP        4995795               135525076170          196534917
MULTICAST   45171                 49866825003           137798118
GIGAPOP     942209                26422533266           23199961
SPART       73998                 5170323905            7597985


Configuration files: Symbols - /usr/local/etc/flow-tools/*. Tag - /usr/local/etc/flow-tools/tag.cfg.


None known.


Mark Fullmer <>



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FLOW-TAG (1) 26 Август 2010

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