ref: 2fe3b28f86ed4aa291fb8a620b948abe9c6a1f84
dir: /sys/man/8/udpecho/
.TH UDPECHO 8 .SH NAME udpecho \- echo UDP packets .SH SYNOPSIS .PP .B ip/udpecho [ .B -x .I ext ] .SH DESCRIPTION .PP Listen on UDP port 7 and echo back any packets received. This should only be run for testing since it can be used to disguise the identity of someone doing a denial of service attack.