如何在Unix/Linux上使用perl执行批量DNS查询？

#!/usr/bin/perl

use strict;
use warnings;
use Net::DNS;

# 创建一个Net::DNS对象
my $res = Net::DNS::Resolver->new;

# 设置查询超时时间（秒）
$res->timeout(2);

# 设置重试次数
$res->retry(2);

# 要查询的域名列表
my @domains = qw(www.google.com www.baidu.com www.sina.com);

# 遍历域名列表，执行DNS查询
foreach my $domain (@domains) {
    print "Querying $domain...\n";

    # 执行A记录查询
    my @a_records = mx($domain);

    # 打印查询结果
    if (@a_records) {
        print "MX records for $domain:\n";
        foreach my $a_record (@a_records) {
            print "\t", $a_record->exchange, "\n";
        }
    } else {
        print "No MX records for $domain\n";
    }
}

cpan install Net::DNS