test-dns.sh

#!/bin/bash

set -eu

count="$1"
test_name="$2"
dns_server="$3"
total=0

for (( i = 0 ; i <= count ; i++ ))
{ 
  now="$(date +%s)"
  dig="$(dig +short "${test_name}" "@${dns_server}")"
  dig="${dig:-NONE}"
  then="$(date +%s)"
  elapsed="$((then-now))"
  total="$((total+elapsed))"
  echo $now,$dig,$elapsed
}

bc -l <<< "scale = 2;${total} / ${count}" > /dev/stderr