Provided by: nfdump_1.7.3-1build2_amd64 
NAME
nfdump — flow display and analysis program
SYNOPSIS
nfdump -r flowpath [-w outfile] [-f filterfile] [-C config] [-R filelist] [-M dirlist] [-O order]
[-t timewin] [-c num] [-a] [-A aggregation] [-b] [-B] [-I] [-D nameserver] [-G geoDB]
[-s statistic] [-n num] [-o format] [-6] [-q] [-N] [-i ident] [-v flowfile] [-E flowfile]
[-x flowfile] [-z=<compress>] [-J compress] [-X] [-Z] [-T] [-V] [-h] [filter]
DESCRIPTION
nfdump reads the flow data from one or more binary files, created by any nfdump collector nfcapd, nfpcapd
and sfcapd. It processes and lists the flows in many different output formats and can create a wide
range of statistics.
nfdump has a very powerful flow filter to process flows. The filter syntax is very similar to tcpdump,
but adapted and extended for flow filtering. A flow filter may also contain arrays of many thousand IP
addresses etc. to search for specific records.
nfdump can aggreagte flows according to a user defined number of elements. This masks certain elements
and allows to sum up flow records matching the same values.
The combination of flow filtering and aggregation as input for any flow statistics allows complex flow
processing. Pre-filtered and aggregated flow data may also be written back into a binary flow file, which
again may be processed with nfdump
nfdump can enrich the listing of flows with geo location information and AS information, unless AS
information is already available in the flow records. IP addresses can be tagged with a two letter
country code, or with a longer location label containing the geographic region, country and city. The
geo location and AS information is retrieved from the optional geoDB database, created by the geolookup
program from the nfdump tools. geolookup uses the Maxmind database GeoDB or GeoLite2 to create a binary
lookup database for nfdump Please check the geolooup(1) man page for more details.
The options are as follows:
-r flowpath
Reads flow records from this path. flowpath may be a single file, or a directory containing any
number of flow files or sub directories. All files are processed in the order, as listed by the
OS.
-w outfile
Writes all processed records into outfile instead of printing. The flowfile is a binary flow file
and may be processed again with nfdump This can be useful to limit flows according to a flow
filter and/or specific flow aggregation.
-f filterfile
Reads the flow filter from filterfile. This can be useful for very long or structured filters,
with comments and long lists. Note: Any filter specified directly on the command line takes
precedence over the filterfile.
-C config
Read more options from file config. nfdump tries to read by default %prefix/etc/nfdump.config.
This may be overwritten by the environment valiable NFCONF which again may be overwritten by this
option -C. In order to prevent reading any config file, even if it would exist set -C none. A
config file is not required, but may be handy for often used output formats etc.
-O order
Sets an output order for records to be printed as text output. This order applies after all
records processing, such as filtering, and aggregation and before printing.
flows Sort according to the number of flows
packets Sort according to (in)packets
ipkg Same as packets
opkg Sort according to output packets
bytes Sort according to (in)bytes
ibyte Same as bytes
obyte Sort according to output bytes
pps Sort according to (in)packets per second
ipps Same as ipps
opps Sort according to out packets per second
bps Sort according to (in)bytes per second
ibps Same as bps
obps Sort according to output bytes per second
bpp Sort according to (in)bytes per packet
ibpp Same as bpp
obpp Sort according to output packets
tstart Sort according to start time of flow - former -m
tend Sort according to end time of flows
duration Sort according to duration of flows
-t timewin
Set time window to process flows. This option is considered legacy andmay be replaced with a
filter primitive in future rleases. The time window is specified as:
YYYY/MM/dd.hh:mm:ss[-YYYY/MM/dd.hh:mm:ss]. Any parts of the time spec may be omitted e.g
YYYY/MM/dd expands to YYYY/MM/dd.00:00:00-infinity and processes all flow from a given day
onwards. The time window may also be specified as +/- n. In this case it is relative to the
beginning or end of all flows. +10 means the first 10 seconds of all flows, -10 means the last 10
seconds of all flows.
-c num Limit the number of records to be processed to the first num records, which passwd the filter.
-a Aggregate flow records. The default aggregation is done at connection level by taking the 5-tuple
protocol, srcip, dstip, srcport and dstport. This way of aggregation may be overwritten by option
-A
-A aggregation
Sets the list of elements in a flow record to be aggregated. aggregation is a ',' separated list
of any number of v9/ipfix elements. The following elements are accepted:
proto IP protocol
srcip Source IP address
dstip Destination IP address
srcip4/net IPv4 source IP address with applied netmask
srcip6/net IPv6 source IP address with applied netmask
dstip4/net IPv4 destination IP address with applied netmask
dstip6/net IPv6 destination IP address with applied netmask
srcnet Apply netmask srcmask in netflow record for source IP
dstnet Apply netmask dstmask in netflow record for dest IP
srcport Source port
dstport Destination port
srcmask Source mask
dstmask Destination mask
srcvlan Source vlan label
dstvlan Destination vlan label
srcas Source AS number
dstas Destination AS number
nextas BGP Next AS
prevas BGP Previous AS
inif SNMP input interface number
outif SNMP output interface number
next IP next hop
bgpnext BGP next hop
insrcmac In source MAC address
outdstmac out destination MAC address
indstmac In destination MAC address
outsrcmac Out source MAC address
tos Source type of service
srctos Source type of Service
dsttos Destination type of Service
mpls1 MPLS label 1
mpls2 MPLS label 2
mpls3 MPLS label 3
mpls4 MPLS label 4
mpls5 MPLS label 5
mpls6 MPLS label 6
mpls7 MPLS label 7
mpls8 MPLS label 8
mpls9 MPLS label 9
mpls10 MPLS label 10
router IP address of exporting router
odid observation domain ID
opid observation point ID
xsrcip X-late source IP address, if compiled with NSEL support
xdstip X-late destination IP address, if compiled with NSEL support
xsrcport X-late source port, if compiled with NSEL support
xdstport X-late destination port, if compiled with NSEL support
nfdump automatically compiles the appropriate output format for the selected aggregation elements
unless an explicit output format -o is given. The automatic output format is identical to
-o 'fmt:%ts %td <fields> %pkt %byt %bps %bpp %fl'
where <fields> represents the selected aggregation tags.
-b Aggregate flow records as bidirectional flows. This automatically implies -a. Aggregation is
done on connection level by taking the 5-tuple protocol, srcip, dstip, srcport and dstport The
reverse order applies for the corresponding reverse flow. Input and output packets/bytes are
counted and reported separately. Both flows are merged into a single record with corresponding
input and output counters. An appropriate output format is selected automatically, which may be
overwritten by any -o format option.
-B Similar to option -b but tries to guess the correct client to server direction. Automagically
swaps flows if src port is < dst port for TCP and UDP flows and src port < 1024 and dst port >
1024. Some exporters do not really care sending the flows in proper order. It's considered to
be a conveniency option.
-I Print flow statistics of a single file or the summary of all the files specified by -r flowpath.
-g Print for each flow file given by -r flowpath a one line summary, which can be easily used by gnu
plot.
-D nameserver
Sets the nameserver to translate hostnames into IP addresses in filter expressions. See filter
below for more details.
-G geoDB
Use geoDB as geo lookup DB for geo location and AS lookups. nfdump tries to read the environment
variable NFGEODB for the path of geoDB. The option -G overwrites NFGEODB. In order to prevent
reading any geoDB file, even if it would exist set -G none.
-s statistic [:p [/orderby]]
Generate the Top N flow record or flow element statistic. By optionally adding :p to statistic,
the statistic is additionally split up into the transport layer protocols. By default the
statistic is transport protocol independent. Each statistic may be ordered by the optional
parameter orderby This can be flows, packets, bytes, pps, bps or bpp. You may specify more than
one orderby option, which results in the same statistic but ordered differently. If no orderby is
given, the statistic is ordered by flows. You can specify as many -s flow element statistics as
needed on the command line for the same run.
statistic can be:
record aggregated netflow records.
srcip source IP addresses
dstip destination IP addresses
ip any (src or dst) IP addresses
nhip next hop IP addresses
nhbip BGP next hop IP addresses
router exporting router IP address
srcport source ports
dstport destination ports
port any (source or destination) ports
tos type of service - default src
srctos src type of service
dsttos dst type of service
dir flow directions ingress/egress
srcas source AS numbers
dstas destination AS numbers
srcgeo 2 letter geo source country code
dstgeo 2 letter geo destination country code
as any (source or destination) AS numbers
inif input interface
outif output interface
if any interface
inam input interface name
onam output interface name
srcmask src mask
dstmask dst mask
srcvlan src vlan label
dstvlan dst vlan label
vlan any vlan label
insrcmac input src MAC address
outdstmac output dst MAC address
indstmac input dst MAC address
outsrcmac output src MAC address
srcmac any src MAC address
dstmac any dst MAC address
inmac any input MAC address
outmac any output MAC address
mask any mask
proto IP protocols
mpls1 MPLS label 1
mpls2 MPLS label 2
mpls3 MPLS label 3
mpls4 MPLS label 4
mpls5 MPLS label 5
mpls6 MPLS label 6
mpls7 MPLS label 7
mpls8 MPLS label 8
mpls9 MPLS label 9
mpls10 MPLS label 10
sysid Internal SysID of exporter
nbar nbar ID
ja3 ja3 hashes
odid observation domain ID
opid observation point ID
vrf/ivrf ingress vrf
evrf egress vrf
ivrfnam ingress vrf name
evrfnam egress vrf name
NSEL/ASA statistics
event NSEL/ASA event
xevent NSEL/ASA extended event
xsrcip NSEL/ASA translated src IP address
xsrcport NSEL/ASA translated src port
xdstip NSEL/ASA translated dst IP address
xdstport NSEL/ASA translated dst port
iacl NSEL/ASA ingress ACL
iace NSEL/ASA ingress ACE
ixace NSEL/ASA ingress xACE
eacl NSEL/ASA egress ACL
eace NSEL/ASA egress ACE
exace NSEL/ASA egress xACE
NAT statistics
nevent NAT event
nsrcip NAT src IP address
nsrcport NAT src port
ndstip NAT dst IP address
ndstport NAT dst port
% nfdump -s srcip -s ip/flows/bytes -s record/bytes
-n num Set the number of records to be printed to num. This option applies to -s statistics as well as
to ordered output -O -or -aggregated -records -a The default is set to 10 for statistics and
unlimited for the other use cases. To disable the limit, set num to 0.
-o format
Sets the output format to print flow records. has many different output formats already
predefined. format may be one of the options below:
raw Print the full flow record on multiple lines. This prints all available information.
fmt: user Print the flow records according the format user. This is a very flexible and powerful
way to format flow records. See the section OUTPUT below for more details on how to
compile your own format.
json Print full record as a separate json object.
csv Legacy .csv format - will get removed in future releases. Please use json instead.
pipe Legacy '|' separated format - will get removed in future releases. Please use json
instead.
Already predefined fmt formats:
line Print each flow on one line. Default format.
long Print each flow on one line with more details
biline Same as line, but for bi-directional flows
bilong Same as long, but for bi-directional flows
gline Same as line, but add country code to IPs. If a geoDB file is supplied this is the
default output format
glong Same as long, but add country code to IPs
extended Print each flow on one line with even more details.
nsel Print format for NSEL event records. Default format if NSEL/NAT support has been
compiled in.
nel Print format for NAT event records.
The nfdump config file may contain additional formats. If you want to add new formats or change
existing ones, check the config file.
IPv6 addresses are printed condensed in any fmt defined format to prevent cluttering the output
with large blank blocks. A condensed IPV6 uses max 16 characters. If it is longer, then the
middle part of the IP is cut out and replaced be "..". For previewing an output, this fits most
needs. For a listing with the full IPV6 addresses add option -6.
-6 Print full length of IPv6 addresses in output instead of condensed.
-q Quiet mode. Suppress the header line and the statistics at the bottom of text outputs.
-N Print plain numbers in output without scaling. Easier for output parsing with 3rd party tools.
-i ident
Change the ident label in the file, specified by -r to ident
-v flowfile
Verify the consistency of flowfile and print the file parameters and number of records.
-E flowfile
Print the exporter and sampler list if found in flowfile. Additional statistics per exporter are
printed with number of flows, packets and sequence errors.
-x flowfile
This options works on nfdump version 1.6.x files only and may get removed in future. Scans and
prints extension maps located in flowfile
-z=lzo Compress flow files with LZO1X-1 compression. Fastest compression.
-z=lz4 Compress flow files with LZ4 compression. Fast and efficient.
-z=bz2 Compress flow files with bz2 compression. Slow but most efficient. May be used for archiving
files or if you are really short of spce.
-J compress
Change compression for any number of files given by option -r flowpath Set compress to 0 for no
compression or to any of: 1 or LZO, 2 or BZ2, 3 or LZ4. This option may be used for archiving
flow files and changing the compression to use less disk space.
-X Compiles the filter syntax and dumps the filter engine table to stdout. This is for debugging
purpose only.
-Z Check filter syntax and exit. Sets the return value accordingly.
-R filelist
Select a range of files. This option is mainly used by old NfSen and documented here as legacy
option.
/any/dir Read recursively all files in directory dir.
/dir/file Read all files beginning with file.
/dir/file1:file2 Read all files from file1 to file2.
When using in combination with a sub hierarchy: /dir/sub1/sub2/file1:sub3/sub4/file2 Read all
files from sub1/sub2/file1 sub3/sub4/file2 iterating over all required hierarchy levels. Note:
files are read in alphabetical order.
-M dirlist
Read the same file hierarchy from multiple directories. This option is mainly used by old NfSen
and documented here as legacy option. Example: /any/path/to/dir1:dir2:dir3 etc. and will be
expanded to the directories: /any/path/to/dir1, /any/path/to/dir2 and /any/path/to/dir3. Any
number of colon separated directories may be given. The files to read are specified by -r or -R
and are expected to exist in all the given directories. The options -r and -R must not contain
any directories when used in combination with -M.
-T Tag IP addresses with a prepending cntrl-A character, to allow output parsers to hook in. This
option is mainly used by old NfSen and documented here as legacy option.
-V Print nfdump version and exit.
-h Print help text on stdout with all options and exit.
filter selects, which records will be further processed. If no filter is given, all records will be
processed. Otherwise, only those flows matching the filter will be processed. Any IP address in a filter
may be specified as IPv4 or IPv6.
The filter syntax is similar to tcpdump but adapted and extended for flow records. The filter can be
either specified on the command line after all options or in a separate file. It can span several lines.
Anything after a '#' is treated as a comment and ignored to the end of the line. There is virtually no
limit in the length of the filter expression. All keywords are case insensitive.
A single filter primitive filters a single element of a flow record. A filter consists of one or more
primitives, which are linked together:
expr and expr
expr or expr
not expr and (expr)
Possible filter primitives:
@include file Expands the content of file into the current filter
count comp number True if the comparison with the record counter matches number Each record gets
assigned a record number at the time it is read from file. Therefore this record
number is not unique and may change, depending on the order files are read.
ident string True if the record ident field matches string. This filter can be used to filter out
different sources.
inet
ipv4 True if source and destination IP of a record are IPv4 IPs.
inet6
ipv6 True if source and destination IP of a record are IPv6 IPs.
proto protocol True if the record protocol field matches protocol. protocol can be a symbolic name
such as tcp, udp, icmp, ah, esp, ipip, and many more or a protocol number, such as 6,
17 for protocol tcp and udp.
tun proto protocol True if the record tunnel protocol field matches protocol. protocol may be a symbolic
name or protocol number.
ip ipaddr
src ip ipaddr
dst ip ipaddr True if the respective IP field of the record matches ipaddr. ipaddr may be an IPv4
or IPv6 address or a symbolic hostname. In this case a DNS lookup resolves the
hostname to one or more IP addresses. If more than one IP results, all IPs are
chained together in an or chain. (IP or IP or IP). If ip is not specified with src
or dst the source or destination IP may match.
host ipaddr host is just a synonym for ip (See above)
ip in [iplist]
src in ip [iplist]
dst ip [iplist] True if the respective IP field of the record is in iplist. iplist is a space or ','
separated list of IP addresses or networks in CIDR notation. This is the preferred
way to search in large list of IP addresses and networks and is much more efficient
than to chain all IP addresses together. (IP1 or IP2 or IP3). The iplist may contain
several hundreds to thousand IPs and/or networks. For just a few IPs use an or chain,
otherwise use an iplist If ip is not specified with src or dst the source or
destination IP may match.
net network netmask
src net network netmask
dst net network netmask
net network/netbits
src net network/netbits
dst net network/netbits
True if the respective IP field of the record matches the network if the
corresponding netmask or netbits are applied to the IP address. If net is not
specified with src or dst the source or destination IP may match.
geo geoloc
src geo geocode
dst geo geocode True, if the 2-letter country code resolved by geolookup of the source or destination
IP address matches geocode. This filter works only, if a valid geoDB is specified.
See geo location option above. The 2-letter country code corresponds to the maxmin DB
definitions. if geo is not specified with src or dst the source or destination geo
location code may match.
tunip ipaddr
src tunip ipaddr
dst tunip ipaddr True if the respective tunnel IP field of the record matches ipaddr. If tunip is not
specified with src or dst the source or destination tunnel IP may match.
port comp num
src port comp num
dst port comp num True if the comparison of the respective port field matches num See comp for the
comparator details. If port is not specified with src or dst the source or
destination port may match.
port in [portlist]
src port in [portlist]
dst port in [portlist]
True if the respective port field of the record is in portlist. portlist is a space
or ',' separated list of port numbers. This is the preferred way to search in large
list of port numbers and is much more efficient than to chain all ports together.
(PORT1 or PORT2 or PORT3). portlist may contain several hundreds to thousand of port
numbers. If port is not specified with src or dst the source or destination port may
match.
icmp-type num
icmp-code num True if the respective icmp field of the record matches num. This automatically
implies proto icmp.
engine-type num
engine-id num
sysid num True if the respective fields of the record matches num engine type and ID are set by
the exporting device, sysid refers to the nfdump collector internal assigned number.
See also option -E above.
if num
in if num
out if num True if the respective interface fields of the record matches num. This ID may
correspond to the SNMP ID of the interface but depends on the exporter. If if is not
specified with in or out the input or output interface may match.
as comp num
src as comp num
dst as comp num
prev as comp num
next as comp num True if the comparison of the respective AS fields matches nfdump supports 32-bit AS
numbers every where. Without or the source or destination AS may match. See comp for
the comparator details.
as in [aslist]
src as in [aslist]
dst as in [aslist]
prev as in [aslist]
next as in [aslist]
True if the respective AS field of the record is in aslist. aslist is a space or ','
separated list of AS numbers. This is the preferred way to search in large list of
AS numbers and is much more efficient than to chain all ports together. aslist may
contain several hundreds to thousand of AS numbers. If as is not specified with src,
dst, prev or next the source or destination AS may match.
mask bits
src mask bits
dst mask bits True if the respective mask bit field of the record matches bits If mask is not
specified with src or dst the source or destination mask bits may match.
vlan num
src vlan num
dst vlan num True if the respective vlan field of the record matches num If vlan is not specified
with src or dst the source or destination vlan may match.
flags tcpflags True if the respective tcp flags field of the record matches any of the given
tcpflags. tcpflags is a string combination of all flags to be tested:
A ACK.
S SYN.
F FIN.
R Reset.
P Push.
U Urgent.
X All flags on.
The order of the flags within tcpflags is not relevant. Flags not mentioned are
treated as don't care. In order to get those flows with only the SYN flag set, use
the syntax
flags S and not flags AFRPU
router ip ipaddr True if the ip address of the sending router matches ipaddr as valid IPv4/IPv6
address.
next ip ipaddr True if the field next-ip of the record matches ipaddr as valid IPv4/IPv6 address.
bgpnext ip ipaddr True if the field bgpnext-ip of the record matches ipaddr as valid IPv4/IPv6 address.
mac macaddr
in mac macaddr
in src mac macaddr
in dst mac macaddr
out mac macaddr
out src mac macaddr
out dst mac macaddr
True if the respective mac address field of the record matches macaddr By prepending
mac with any combination of a direction specifier as defined by CISCO v9 the test is
limited to those mac addresses only. Otherwise multiple matches are possible. Without
any specifiers any mac address is tested against macaddr
mpls labelN comp number
True if the comparison of the mpls label N with N as mpls label number 1..10 matches
number Filters according a specific number in the mpls label stack.
mpls eos comp number
True if the comparison of the end of stack mpls label matches number
mpls expN comp number
True if the comparison of the experimental bits 0..7 of mpls label N with N as mpls
label number 1..10 matches number
packets comp num
in packets comp num
out packets comp num
True if the comparison of the packet counter in the flow record matches num. num may
contain any valid scaling factor such as k, m, g Example: packets > 1k. For a single
flow packets and in packets is equivalent and describes the number of packets from
source to destination. In case of a bi-directional flow (sent by an exporter or
combined by option --B ) the packet counter for the reverse flow can be tested with
out packet
bytes comp num
in bytes comp num
out bytes comp num True if the comparison of the byte counter in the flow record matches num. num may
contain any valid scaling factor such as k, m, g Example: bytes > 1k bytes and in
bytes is equivalent and describes the number of bytes from source to destination. In
case of a bi-directional flow (sent by an exporter or combined by option --B ) the
byte counter for the reverse flow can be tested with out bytes
flows comp num True if the comparison of the flow counter in the flow record matches num. num may
contain any valid scaling factor such as k, m, g For each received flow, the flow
counter is set to 1, unless the exporter sends this information. If multiple flows
are aggregated, this counter is increased respectively.
tos num True if the type of service field of the flow record matches num
flowdir direction True, if the flow direction field in the flow record matches direction. direction may
be ingress, egress, 0 for ingress, or 1 for egress
duration comp time True if the calculated duration of a flow (tend - tstart) compares to time. The
duration is specified in msec (milliseconds)
pps comp num True if the calculated value of in-packets/duration (packets per second) compares
with the number num. num may contain any valid scaling factor such as k, m, g
bps comp num True if the calculated value of 8*in-bytes/duration (bits per second) compares with
the number num. num may contain any valid scaling factor such as k, m, g
bpp comp num True if the calculated value of in-bytes/in-packets (bytes per packet) compares with
the number num. num may contain any valid scaling factor such as k, m, g
observation domain id comp number
observation point id comp number
True if the comparison of the observation domain ID or point ID field respectively
matches number
payload filters Some exporters, such as yaf or the nfdump collector nfpcap can send payload data
along the netflow information. If such payloads are sent it can be filtered according
the filter primitives below:
payload content 'string'
True if the string string is found in the payload data. string must be quoted with
single or double quotes: 'string', “string”
payload regex 'regex'
payload regex 'regex' flags
True if regex matches the payload data. regex searches over the full payload length.
A ' ' byte does not stop the match process. regex must be quoted with single or
double quotes: 'regex' or “regex” The regex engine understands the following reduced
syntax:
(...) subexpressions/capture ranges
| the "or" operator
^and $ anchors
[...] and [^...] character classes
?, *, +, simple quantifiers
*?, +?, ?? lazy quantifiers
{<num>}, {<num1>,<num2>} complex quantifiers
flags are optional can be:
m multiline
i case insensitive matching
s
payload ja3 md5string
True, if the payload contains the start of an SSL/TLS handshake and the calculated
jas value of the handshake matches md5string
payload ja3 defined
True, if the payload contains the start of an SSL/TLS handshake and a valid ja3 value
can be calculated. Useful to mask out all flow records with no SSL/TLS traffic in
order to generate a -s ja3 statistic.
OpenBSD pflog implemented elements
pf action action True, if the respective pflog action field compares to one of pass, block, scrub,
noscrub, nat, nonat, binat, nobinat, rdr, nordr, synblock, defer, match, divert, rt,
afrt
pf reason reason True, if the respective pflog reason field compares to one of match, bad-offset,
fragment, short, normalize, memory, bad-timestamp, congestion, ip-option,
proto-cksum, state-mismatch, state-insert, state-limit, src-limit, synproxy,
translate, no-route
pf rule ruleNr True, if the respective pflog rule number field matches ruleNr
pf dir in|out True, if the respective pflog rule direction field matches in or out
pf interface interfaceName
True, if the respective pflog rule interface name field matches the string
interfaceName
nprobe implemented elements
client latency comp time
server latency comp time
True, if the respective latency field in the flow record compares to time. time is
specified in msec.
CISCO ASA, network security event logging (NSEL) and NAT event logging (NEL) specific filters:
NSEL specific filters:
asa event event True if the NSEL event type of an event record matches event which may be: ignore,
create, term, delete, deny
asa event comp number
True if the comparison of the NSEL event type of an event records matches number as a
number.
asa event denied reason
True if the event denied type of an event records matches reason which may be
ingress, egress, interface, nosyn
asa xevent comp num
True, if the comparison of the extended event field of the event record matches num
xip ipaddr
src xip ipaddr
dst xip ipaddr True, if the field of the translated source or destination IP address matches ipaddr
if xip is specified without src or dst both IP addresses may match.
xport ipaddr
src xport ipaddr
dst xport ipaddr True, if the field of the translated source or destination IP address matches ipaddr
if xport is specified without src or dst both ports may match.
xnet network/mask
src xnet network/mask
dst xnet network/mask
True if the translated source or destination IP address matches network if mask mask
is applied. if xnet is specified without src or dst both IP addresses may match.
ingress ACL comp number
ingress ACE comp number
ingress XACE comp number
True if the comparison of the respective ingress field matches number
egress ACL comp number
True if the comparison of the egress field matches number
NEL specific filters:
nat event event True if the NEL event type of an event record matches event. event may be add, delete
nat event comp number
True if the comparison of the NEL event type of an event records matches number as a
number.
nip ipaddr
src nip ipaddr
dst nip ipaddr True, if the field of the nat source or destination IP address matches ipaddr if nip
is specified without src or dst both IP addresses may match.
It Cm nport Ar number
src nport number
dst nport number True, if the field of the nat source or destination port matches number if nip is
specified without src or dst both ports may match.
ingress vrf number True, if the field of the ingess vrf field of the event record matches number
pblock start comp number
pblock step comp number
pblock end comp number
True if the comparison of the start, step or end of the NAT port block in the event
record matches number
port in pblock
src port in pblock
dst port in pblock True, if the source or destination port field matches the NAT port block range
comp Many filter elements support the comparison with a number. The following comparators
are supported for each of those filters: =, ==, >, <, >=, <= To prevent collisions
with bash interpretation, alternative comparators are available: EQ, LT, GT, LE, GE
If comp is omitted, '==' is assumed.
OUTPUT FORMAT
This section describes how output formats are compiled. nfdump has a lot of already pre-defined output
formats such as raw, json, csv etc. One line formats as described for option -o can be compiled from
various elements of a flow record. As a flow record can contains man different elements it is often
useful to compile an output format for specific needs.
Format description
The output format is specified by -o “fmt: string” string contains the field tags to be printed as well
as other characters if needed. A tag starts with a % sign followed by the field name. tags are separated
by spaces from other tags. Characters or other strings, not starting with a % sign are copied literally
to the output.
Example:
-o “fmt:%ts %td %pr %sap -> %dap %pkt %byt %fl”
This is the definition of the predined format line. It adds the elements tstart duration protocol source
IP address/port followed by the literal characters -> and destination ip address/port packets, bytes,
flows counter. Depending on the task, different output formats are required to see the required fields of
a flow record. You can either extend a predefined format or specify a new one at the command line.
Example: Extend the predefined format long with the the IP address of the sending router
-o “fmt:%long %ra”
Predefined formats can be extended by simply add their name with a % sign somewhere in the format string.
As described under the output option -o
Format definition
nfdump has already many formats predefined. Most of the time, these format are good enough. Sometimes you
may need different formats, which can be compiled as described above. In order to prevent adding the same
often used output format each time you run nfdump a new output format may be define in the config file
nfdump.conf The file nfdump.conf.dist contains the definition of the already hard coded formats. These
may be uncommented and changed according to the specific needs. New formats may be added using the
following syntax:
fmt.newname = “fmt:%ts %td %pr %sap -> %dap %pkt %byt %fl”
with newname any new or existing definition of output formats. Existing formats are overwritten with the
new definition.
Tag definition
The following list contains all tags, which are available to compile the output format:
%<format>
Inserts the predefined format at this position. e.g. %line
%cnt Record counter. record numbers are assigned dynamically assigned while reading read from
file.
%nfv Netflow version.
%ts Start Time - first seen
%tfs First seen - identical to %ts
%tsr Start Time, but in fractional seconds since the epoch (1970-01-01) UNIX format.
%te End Time - last seen
%ter End Time, in fractional seconds
%tr Time the flow was received by the collector
%trr Time the flow was received, in fractional seconds
%td Duration of flow. Displayed in ddHHMMSS.msec
%pr Transort protocol
%exp Exporter ID
%eng Engine Type/ID
%lbl Flowlabel
%sa Source Address
%da Destination Address
%sap Source Address:Port
%dap Destination Address:Port
%gsap Source Address(country code):Port
%gdap Destination Address(country code):Port
%sp Source Port
%dp Destination Port
%it ICMP-type
%ic ICMP-code
%sn Source Network, mask applied
%dn Destination Network, mask applied
%nh Next-hop IP Address
%nhb BGP Next-hop IP Address
%ra Router IP Address
%sas Source AS
%das Destination AS
%nas Next AS
%pas Previous AS
%in Input Interface num
%out Output Interface num
%pkt Packets - default input
%ipkt Input Packets
%opkt Output Packets
%byt Bytes - default input
%ibyt Input Bytes
%obyt Output Bytes
%fl Flows
%flg TCP Flags
%tos Tos - default src
%stos Src Tos
%dtos Dst Tos
%dir Direction: ingress, egress
%smk Src mask
%dmk Dst mask
%fwd Forwarding Status
%svln Src vlan label
%dvln Dst vlan label
%ismc Input Src Mac Addr
%odmc Output Dst Mac Addr
%idmc Input Dst Mac Addr
%osmc Output Src Mac Addr
%mpls1 MPLS label 1
%mpls2 MPLS label 2
%mpls3 MPLS label 3
%mpls4 MPLS label 4
%mpls5 MPLS label 5
%mpls6 MPLS label 6
%mpls7 MPLS label 7
%mpls8 MPLS label 8
%mpls9 MPLS label 9
%mpls10 MPLS label 10
%mpls MPLS labels 1-10
%bps bps - bits per second
%pps pps - packets per second
%bpp bps - Bytes per package
%sc src IP 2 letter country code
%dc dst IP 2 letter country code
%sloc src IP geo location info
%dloc dst IP geo location info
%sasn src AS organisation name
%dasn dst AS organisation name
%n new line char \n
%ipl input payload
%opl output payload
%nbid nbar ID
%ja3 ja3 hash
%sni sni name in tls handshake
%nbnam nbar name
%odid observation domainID
%opid observation pointID
OpenBSD pflog specific formats
%pfifn pflog interface name
%pfact pflog action
%pfrea pflog reason
%pfdir pflog direction
%pfrule pflog rule nr
NSEL specific formats
%nfc NSEL connection ID
%evt NSEL event
%xevt NSEL extended event
%sgt NSEL Source security group tag
%msec NSEL event time in msec
%iacl NSEL ingress ACL
%eacl NSEL egress ACL
%xsa NSEL XLATE src IP address
%xda NSEL XLATE dst IP address
%xsp NSEL XLATE src port
%xdp NSEL SLATE dst port
%xsap Xlate Source Address:Port
%xdap Xlate Destination Address:Port
%uname NSEL user name
NEL/NAT specific formats
%nevt NAT event - same as %evt
%ivrf NAT ingress VRF ID
%evrf NAT egress VRF ID
%nsa NAT src IP address
%nda NAT dst IP address
%nsp NAT src port
%ndp NAT dst port
%pbstart NAT pool block start
%pbend NAT pool block end
%pbstep NAT pool block step
%pbsize NAT pool block size
Nprobe formats
%cl Client latency
%sl Server latency
%al Application latency
EXAMPLES
nfdump processes files created by any previous version of nfdump 1.6.x with some limitations for versions
< 1.6.17. In order to convert flow files to the new 1.7.x binary format use the following command to
read//write files:
% nfdump -r oldfile -w newfile
Print a statistic about the top 20 IP addresses, once sorted by flows and once by bytes
% nfdump -r flowfile -s ip/flows/bytes -n 20
Print two statistics, one about the source IP and one about the destination IP address limited to flow
with either source or destination port 443
% nfdump -r flowfile -s srcip/bytes -s dstip/bytes -n 20 'port 443'
Print a statistic about the IP pairs, which exchanged most traffic.
% nfdump -r flowfile -s record/bytes -A srcip,dstip
Print all flows in raw format with a HTTP header in the payload even if flow is not on port 80.
% nfdump -r flowfile -o raw “payload regex 'GET|POST'”
Print a statistic about all ja3 md5 sums for those flows, which a valid ja3 can be calculated
% nfdump -r flowfile -s ja5 -n 0 'payload ja3 defined'
Aggregate all flows and write the result back to a binary file, sorted by the start time
% nfdump -r flowfile -a -Otstart -w newfile
RETURN VALUES
nfdump returns 0 on success and 255 if processing failed.
SEE ALSO
https://www.iana.org/assignments/ipfix/ipfix.xhtml
https://www.cisco.com/en/US/technologies/tk648/tk362/technologies_white_paper09186a00800a3db9.html
nfcapd(1) nfpcapd(1) sfcapd(1) geolookup(1)
BUGS
No software without bugs! Please report any bugs back to me.
Debian $Mdocdate$ NFDUMP(1)