lft -h

lft -h

Layer Four Traceroute (LFT)

    - the alternative traceroute tool for network [reverse] engineers
                                          visit http://www.pwhois.org

Usage: lft [<options>] [<gateway> <...>] <target:port>

Mainstream Options:
  -s <sport>       Source port number
  -d <dport>       Destination port number (same as using target:port as target)
  -z               Pseudo-randomize the source port number
  -m <min>         Minimum number of probes to send per hop
  -M <max>         Maximum number of probes to send per hop
  -D <device|ip>   Listen-on/use a device by name or address ("en1" or "1.2.3.4")
  -L <length>      Set the length of the probe packet in bytes

Advanced Tracing Options:
  -F               Use TCP FIN packets exclusively (defaults are SYN)
  -f <device|ip>   Send using a device by name or address (spoofing allowed)
  -e | -E          Use LFT's stateful engine to detect firewalls and path anomalies
  -u               Use traditional UDP (probes) for tracing instead of TCP
  -b               Basic TCP trace
  -p               Use traditional ICMP (probes) for tracing instead of TCP
  -a <ahead>       Number of hops forward to query before pausing to wait for replies
  -c <scatter ms>  Minimum number of milliseconds between subsequent probes
  -t <timeout ms>  Maximum RTT to wait before assuming packet was dropped
  -l <min ttl>     Minimum TTL to use on outgoing packets (skips close-proximity hops)
  -H <ttl>         Maximum number of hops to traverse (max TTL of packets)
  -q <sequence>    Set the initial sequence number (ISN) manually
  -I               Set the ToS field in the IP packet to minimize-delay
  -i               Disable "stop on ICMP" other than TTL expired

Resolution Options:
  -n               Display hosts numerically; disable use of the DNS resolver
  -h               Display hosts symbolically; suppress IP address display
  -N               Display network or AS names where appropriate
  -A               Display AS numbers resolved by Prefix WhoIs

Advanced Resolution Options:
  -r               Use RIPE NCC's RIS to resolve ASNs instead of Prefix WhoIs
  -R               Use the RADB to resolve ASNs instead of Prefix WhoIs
  -C               Use Cymru to resolve ASNs instead of Prefix WhoIs

Verbosity Options and Status:
  -T               Use execution timers and summarize where LFT spent its time
  -U               Display all times in UTC (GMT0).  Activates -T option automatically
  -S               Disable the status bar (only show the completed trace)
  -V               Display verbose/debug output.  Use more 'V's for additional detail
  -x               XML output
  -g               GraphViz output
  -G <icons path>  Enable GraphViz output and override path to icons
  -y               Test destination upstream transition hop
  -v               Display LFT's version information and exit

Default is: lft -s 53 -d 80 -m 1 -M 2 -a 5 -c 20 -t 250 -H 30

See also

• lft, lft -h
• IP: route, mtr, traceroute, tcptraceroute, lft, TTL