How to add multiple host in shell script

Question

I am trying to run below script & it's working fine for one host but I want to add multiple host.

host=1.2.3.4
LOG_OK=/tmp/port-check-success.log
LOG_FAIL=/tmp/port-check-failed.log

for port in 80 443
do
if telnet -c $host $port </dev/null 2>&1 | grep -q Escape; then
  echo  "$port: Connected" >> $LOG_OK
else
  echo "$port : no connection" >> $LOG_FAIL
fi
done

Answer 1

Just have a for loop for host in the same way that you are already doing for port, and nest one loop inside the other. For example:

LOG_OK=/tmp/port-check-success.log
LOG_FAIL=/tmp/port-check-failed.log

for host in 1.2.3.4 5.6.7.8
do
    for port in 80 443
    do
        if telnet -c $host $port </dev/null 2>&1 | grep -q Escape; then
            echo "$host: $port: Connected" >> $LOG_OK
        else
            echo "$host: $port : no connection" >> $LOG_FAIL
        fi
    done
done