Ping in Bash Parallel [closed]

Question

I am trying to ping a range of IP addresses using Bash and generate a CSV file with the results.

My current code is as follows:

CSV_FILE="ping_results.csv"
echo "IP Address,Status" > $CSV_FILE

for i in {1..254}; do (host 10.184.2.$i | grep "name pointer" >/dev/null && echo "10.184.2.$i;Ping_Yes;$(host 10.184.2.$i | awk '{print $5}' | tr -d '.')" >> ping_results.csv || ping 10.184.2.$i -c 1 -w 5 >/dev/null && echo "10.184.2.$i;Ping_Yes;" >> ping_results.csv) &
done

echo "Ping-Ergebnisse wurden in ping_results.csv gespeichert."

The issue I'm facing is that sometimes the code reports that an IP address is pingable, but when I try to ping it manually, it's not actually reachable. I need help understanding why this is happening and how I can improve the code to ensure that the CSV file only contains accurate information about which IP addresses are actually pingable.

Ideally, the CSV file should contain the following information for each IP address:

• IP Address
• Status (Ping_Yes or Ping_No)
• Hostname

My goal is to have a reliable and accurate CSV file that correctly identifies the pingable and non-pingable IP addresses within the specified range. How can I achieve this?

---

Here is the above code written more legibly:

CSV_FILE="ping_results.csv"
echo "IP Address,Status" > $CSV_FILE

for i in {1..254}; do
    (
        host 10.184.2.$i |
        grep "name pointer" >/dev/null &&
        echo "10.184.2.$i;Ping_Yes;$(host 10.184.2.$i | awk '{print $5}' | tr -d '.')" >> ping_results.csv ||
        ping 10.184.2.$i -c 1 -w 5 >/dev/null &&
        echo "10.184.2.$i;Ping_Yes;" >> ping_results.csv
    ) &
done

echo "Ping-Ergebnisse wurden in ping_results.csv gespeichert."

Answer 1

How I will parallelize multi scan

... And multiple host names resolution.

Note: As you stand for

• IP Address
• Status (Ping_Yes or Ping_No)
• Hostname

My CSV will contain 3 columns: IP Address,Status,Hostname.

csvFile="ping_results.csv"
baseIP=10.184.2

. <(
    for i in {1..254};do
        host $baseIP.$i &
    done |
    sed -ne 's/^\([0-9]\+\)\.[0-9]\+\.[0-9]\+\.[0-9]\+\.in.*pointer \(.*\)\./hosts[\1]=\2/p'
)

. <(
    for i in {1..254}; do
        if ping -nW5 -c1 $baseIP.$i &>/dev/null; then
            echo ping[$i]=Ping_Yes
        else
            echo ping[$i]=Ping_No
        fi &
    done
)

{
    echo IP Address,Status,Hostname
    for i in ${!ping[@]}; do
        echo $baseIP.$i,${ping[i]},${hosts[i]:-unknown}
    done
} >$csvFile