Scripts to resolve domains to IPs

convert.awk

/NXDOMAIN/ {print $2, "?"; next}
/SERVFAIL/ {print $2, "?"; next}
/mail is handled by/ {next}

/is an alias for/ {doms[$6]=$1; next}

{
    if ($1"." in doms)
        print doms[$1"."], $4
    else if (match($0, "has IPv6 address"))
        print $1, $5
    else
        print $1, $4
}

# This script processes a domain list such as this one
# example.com has address 93.184.216.34
# example.com has IPv6 address 2606:2800:220:1:248:1893:25c8:1946
# example.com mail is handled by 0 .
# Host nx.example.com not found: 3(NXDOMAIN)
#
# and outputs the following format
# $ awk -f convert.awk domains-resolved.txt
# example.com 93.184.216.34
# example.com 2606:2800:220:1:248:1893:25c8:1946
# nx.example.com ?

resolve.sh

#/urs/bin/env bash
xargs -n 1 host 2>&1

# cat domains.txt | ./resolve.sh | tee domains-resolved.txt
# Be careful about line terminators on the input. Ensure \n only is used, UNIX style.