query domain's nameservers for zone/axfr

axfr.sh

#!/bin/sh

ME="${0}"
FAIL='Transfer failed.'
count=$#

help() {
	echo "USAGE:
  ${ME} domain[s]

EXAMPLES:  ${ME} example.com
           ${ME} google.com facebook.com goo.ne.jp linkbucks.com amazon.com ebay.com"
	
}


# args
[ ${count} -le 0 ] &&  { echo >&2 "$(help)" ; exit 1; }
[ "$1" = "-h" -o "$1" = "--help" ] &&  { help; exit 0; }
domains="$@"

# dig installed?
hash dig 2>/dev/null || { echo >&2 "I require dig but it's not installed."; exit 1; }

c=1
for domain in $domains ; do
	echo "==================== $domain (${c}/${count}) ===================="

	# get NS
	servers="$(dig $domain NS +short)"
	
	for server in $servers ; do
		printf ">> Server $server: "
		axfr="$(dig AXFR ${domain} @${server})"
		
		# transfer failed
		if echo "$axfr" | grep -q "${FAIL}" ; then
			echo "${FAIL}"
		# success
		elif echo "$axfr" | grep -q 'records' ; then
			echo "${axfr}" #| grep -Ev '^;'
			break
		# else (timeout etc.)
		else
			echo "${axfr}"
		fi
	done
	c=$(( $c + 1 ))
done