Shell script: Ping All IPs of a network segment and display the current time in one second

Label: shell script ping all ips on the same network segment

The environment is centos7 / bin / bash

Note When copying the test, be sure to change the ip network segment in the example to your own ip network segment.

ctrl + z can enter the script into the background, and then kill the process.

1.

#! / bin / bash



for i in {1..254} #define 1 to 254

do

HOST = 192.168.168. $ I

ping -c 2 $ HOST &> / dev / null

if [$? -eq 0]; then # -eq Determine if the return value is 0 $? A value of 0 means the execution result is correct

echo "$ HOST IS UP"

else

echo "$ HOST IS DOWN"

fi

done



2.

#! / bin / sh



ip = "192.168.168."

for i in {1..254} #define 1 to 254 IP numbers

#for i in `seq 1 254` can also be expressed like this

do

  ping -c 2 $ ip $ i | grep -q ‘ttl =‘ && echo "$ ip $ i yes" || echo "$ ip $ i no"

#ping -c 2 ping2 times Filter ttl in the output. If ttl =, then output echo "$ ip $ i yes otherwise output no

done



3.

#! / bin / sh



ip = 1 #Describe the starting IP

while [$ ip! = 254]; # ip max

do

ping 192.168.168. $ ip -c 2 | grep -q ‘ttl =‘ && echo "192.168.168. $ ip yes" || echo "192.168.168. $ ip no"

ip = `expr" $ ip "" + "" 1 "` # $ ip + 1 every time

done



Display the current time every second

#! / bin / bash

for now in {1..5000};

do

echo "current time: $ (date‘ +% T ‘)”; #date only takes the time parameter

sleep 1; #delay for one second

done





Shell script: ping all IPs on a network segment and display the current time every second