The detection port is still using telnet? too outdated
Is there a way to batch detection? some. We can use nc to quickly detect the openness of the port.
Usage of nc detection port
nc -z -w 10% IP%% PORT%
-z means to detect or scan the port
-w means the timeout time
-u means to use the UDP protocol
E.g:
[@s136.ipcpu.com ~]# nc -z -w 10 -u 8.8.8.8 53
Connection to 8.8.8.8 53 port [udp/domain] succeeded!
[@s136.ipcpu.com ~]# nc -z -w 10 8.8.8.8 53
Connection to 8.8.8.8 53 port [tcp/domain] succeeded!
[@s136.ipcpu.com ~]# echo $?
0
[@s136.ipcpu.com ~]# nc -z -w 10 8.8.8.7 53
[@s136.ipcpu.com ~]# echo $?
1
[@s136.ipcpu.com ~]#
If the port is successfully connected, the return value is 0, indicating succeeded; otherwise, it returns 1, indicating no data.
Suppose we have such a bunch of IPs and ports.
#cat test.txt
119.181.69.96 8080
119.181.118.38 8000
119.181.20.18 8080
119.181.69.37 8080
cat test.txt | while read line
do
#nc -z -w $ 10 line
nc -z -w 10 $line > /dev/null 2>&1
if [ $? -eq 0 ]
then
echo $line:ok
else
echo $line:fail
be
done