NAME

sc_radargun — scamper driver to run radargun on a list of candidate aliases.

SYNOPSIS

DESCRIPTION

The sc_radargun utility provides the ability to connect to a running scamper(1) instance and infer which of the supplied IPv4 addresses are aliases using the Radargun technique. For all addresses in the file, sc_radargun establishes which probe methods (UDP, TCP-ack, ICMP-echo) solicit an incrementing IP-ID value, and then uses the Radargun technique on addresses where a probe method is able to obtain an incrementing IP-ID for the addresses. The output is written to a warts file. The options are as follows:

-?

prints a list of command line options and a synopsis of each.

-D

causes sc_radargun to detach and become a daemon.

-a infile

specifies the name of the input file which consists of a list of IPv4 addresses. The file can either contain sets to test, one set per line, or simply one set, one address per line.

-d dump

specifies the dump ID to use to analyze the collected data. The current choices for this option are:

• 1: dump inferred aliases.
• 2: dump interface classifications.

-f fudge

specifies the fudge to use when inferring if a device is deriving IP-ID values from a counter. By default, responses the maximum difference between two samples must be no larger than 5000. The fudge value also impacts alias inference. If a value of zero is used, the IP-ID samples must simply be in order.

-o outfile

specifies the name of the output file to be written. The output file will use the warts format.

-O options

allows the behavior of sc_radargun to be further tailored. The current choices for this option are:

• nobs: do not consider if IP-ID values might be byte-swapped in the header
• nobudget: do not consider if the radargun measurement can complete in the round time give the packets-per-second rate specified.
• noradargun: do not conduct radargun step. Stop after classifying interface IP-ID behavior.
• noreserved: do not probe reserved IP addresses.
• rows: the addresses in the input file are supplied in rows, and the radargun measurements will probe and evaluate each set independently.
• tc: when dumping candidate aliases, report the transitive closure, rather than pairs in isolation.

-p port

specifies the port on the local host where scamper(1) is accepting control socket connections.

-P pps

specifies the packets-per-second rate that scamper is running at. The PPS value is used to infer if the radargun measurement can fit in scamper's probe budget.

-q attempts

specifies the number of probe packets to use to when inferring if an IP address assigns IP-ID values from a counter.

-r wait-round

specifies the length of time, in seconds, each round should aim to complete in. By default, 30 seconds.

-R round-count

specifies the number of rounds to pursue in radargun. By default, 30 rounds.

-t logfile

specifies the name of a file to log progress output from sc_radargun generated at run time.

-U unix

specifies the name of a unix domain socket where a local scamper(1) instance is accepting control socket connections.

EXAMPLES

sc_radargun requires a scamper(1) instance listening on a port for commands in order to collect data, at 20 packets per second:

scamper -P 31337 -p 20

will start a scamper(1) instance listening on port 31337 on the loopback interface. To use sc_radargun to infer which addresses might be aliases, listed in a file named set-1.txt

192.0.2.2
192.0.32.10
192.0.30.64
192.0.31.8

the following command will test these IP addresses for aliases using ICMP, UDP, and TCP probes (as appropriate) using the radargun technique with 10 rounds, each round taking 4 seconds:

sc_radargun -a set-1.txt -o set-1.warts -p 20 -r 4 -R 10

To use sc_radargun to infer which addresses might be aliases, listed in a file named set-2.txt organized as sets of candidate aliases to test:

192.0.2.2 192.0.32.10 192.0.30.64 192.0.31.8
192.0.2.3 192.0.32.11 192.0.30.65 192.0.31.9

the following command will test these organized sets of IP addresses for aliases:

sc_radargun -a set-2.txt -o set-2.warts -p 20 -O rows

To use data previously collected with sc_radargun and stored in set-2.warts, to infer likely aliases, reported in pairs:

sc_radargun -d 1 set-2.warts

To use data previously collected with sc_radargun and stored in set-2.warts, to report interface IP-ID classifications:

sc_radargun -d 2 set-2.warts

SEE ALSO

A. Bender, R. Sherwood, and N. Spring, Fixing Ally's growing pains with velocity modeling, Proc ACM Internet Measurement Conference 2008. scamper(1), sc_ally(1), sc_wartsdump(1), sc_warts2json(1)

AUTHORS

sc_radargun was written by Matthew Luckie <mjl@luckie.org.nz>, but the original implementation was by Bender et al.