lft

layer Four Traceroute

TLDR

Traceroute to host

$ lft [hostname]

Use specific port

$ lft -d [80] [hostname]

TCP mode

$ lft -T [hostname]

UDP mode

$ lft -U [hostname]

Show ASN info

$ lft -A [hostname]

Set max TTL

$ lft -m [30] [hostname]

SYNOPSIS

lft [options] host

DESCRIPTION

lft is Layer Four Traceroute. It traces routes using TCP, UDP, or ICMP at layer 4.The tool bypasses many firewalls that block ICMP. It shows AS numbers for network analysis.

PARAMETERS

HOST

Target hostname or IP.

-d PORT

Destination port.

-T

TCP mode.

-U

UDP mode.

-A

Show AS numbers.

-m TTL

Maximum TTL.

-n

No DNS resolution.

--help

Display help information.

INSTALL

sudo apt install lft

brew install lft

CAVEATS

May need root. Firewall-friendly. Network diagnostic tool.

HISTORY

LFT was created by Victor Oppleman as a firewall-friendly alternative to traditional traceroute.