shell script to determine whether there is a domain name resolution records

shell script to achieve from a bunch of domain names to find out what domain name resolution records still exist
records generated demand: to find out what domain name resolution records exist from a bunch of domain names provided by IDC room

First sort remove duplicate domain name:

cat 2.txt |sort -rn|uniq -c|awk '{print $2}' >test

Executing the script sh 2.sh m or sh 2.sh e sh 2.sh unknown or corresponds makefile m.log e.log wujilu.log

[root@intf-06 ~]# cat 2.sh 
#!/bin/sh
list=$(cat /root/test)

for n in $list
do echo $n|tee -a 1.log&&  ping -c1 -i 0.1 $n -q 2>&1 |tee -a 1.log
done

  if [ $1 == "m" ];then
sed  -e '/Done/{d}' -e '/\[1\]/{d}'  1.log|grep -B 1 'PING'|grep "^$1" >m.log
echo "" >1.log
  elif [ $1 == "e" ];then
sed  -e '/Done/{d}' -e '/\[1\]/{d}'  1.log|grep -B 1 'PING'|grep "^$1" >e.log
echo "" >1.log
  elif [ $1 == "未知" ];then
sed  -e '/Done/{d}' -e '/\[1\]/{d}'  1.log|grep "$1"|awk -F '[ :]+' '{print $2}' >wujilu.log
echo "" >1.log
fi

The results obtained are as follows:

以m开头的存在解析记录的二级域名
[root@intf-06 ~]# cat m.log 
m.qxwfc.cn
m.qldua.cn
m.wstzk.cn
m.gsnon.cn
m.fzhxzm.cn
m.ew740.cn

以e开头的存在解析记录的二级域名
[root@intf-06 ~]# cat e.log 
e.gsnon.cn
e.fzhxzm.cn
e.ew740.cn
不存在解析记录的二级域名
[root@intf-06 ~]# cat wujilu.log 
m.0v43q.cn
e.x51se.cn