Reduce the Ping response waiting time 1

[viadisky]

Hi,

I have this script that pings range of addresses, basically the output I get is like this:

172.24.58.1 is alive
172.24.58.2 is alive
172.24.58.3 is alive
no answer from 172.24.58.4
no answer from 172.24.58.5
no answer from 172.24.58.6
no answer from 172.24.58.7
no answer from 172.24.58.8
no answer from 172.24.58.9
172.24.58.10 is alive
no answer from 172.24.58.11
no answer from 172.24.58.12

I want to reduce the waiting time for those devices that didn't respond to ping. It's taking almost 20 seconds for the "no answer from <IP Address>" to appear in the screen.

Is it possible to reduce the waiting time to just at least 5 sec?

Hope somebody can help me.

Many thanks,
Maria

 

[feherke]

Hi

Depends on what kind of [tt]ping[/tt] you have. Look for a -w option.

-w deadline
Specify a timeout, in seconds, before [tt]ping[/tt] exits
regardless of how many packets have been sent or received.

Feherke.

http://rootshell.be/~feherke/

 

[stefanhei]

Hi,

man ping tells you the correct flag for your ping command.
On RH Linux its -W5, on AIX its -w5 for 5 seconds

Stefan

 

[viadisky]

Hi Feherke,

ping -w <deadline> worked on the command-line in my windows XP but it's saying illegal option when I issued the same command in Unix (please refer to the error mesage below)

zen:/u/mviado/ADD_RANGE$ ping -w 1 172.24.58.16
ping: illegal option -- w
usage: ping host [timeout]
usage: ping -s [-l | U] [adLnRrv] [-A addr_family] [-c traffic_class]
[-g gateway [-g gateway ...]] [-F flow_label] [-I interval]
[-i interface] [-P tos] [-p port] [-t ttl] host [data_size] [npackets]


When I did man ping in Unix, I didn't see the "-w" option ...

Cheers!

 

[feherke]

Hi

Sadly, not all [tt]ping[/tt]s have such option. In which case, you end up with a script like in thread822-1156612.

Feherke.

http://rootshell.be/~feherke/

 

[viadisky]

Hi Stefan,

Did I issue the correct ping command?

ping -w 1 172.24.58.16 ?

Thank you.

Maria

 

[viadisky]

Hi Feherke,

I saw the function you wrote to resolve those devices that can hang the script.

###########################################################
function pingw()
{
ping="ping"
while [ $# -ne 0 ]; do
test "$1" == "-w" && { shift; deadline="${1:-1}"; } || ping="$ping $1"
shift
done
$ping &
pid=$!
sec=0
while ps $pid > /dev/null; do
sleep 1
test $((++sec)) -ge "0$deadline" && break
done
ps $pid > /dev/null && kill -SIGINT $pid
}
######################################################

I have no idea how to use this or incorporate this in my script ... my knowledge in unix scripting is quite limited. Can you please give me more info regarding this?

I really appreciate your help ...

Maria

 

[stefanhei]

Maria,
did you try

ping 172.24.58.16 5

?

Stefan

 

[viadisky]

Hi Stefan,

Your suggestion is brilliant !!!

This will complete my script definitely!

Thank you very ... very much!

Maria

 

[p5wizard]

It was already suggested by the ping "usage" messages, but only Stefan noticed it.

zen:/u/mviado/ADD_RANGE$ ping -w 1 172.24.58.16
ping: illegal option -- w
usage: ping host [timeout]
usage: ping -s [-l | U] [adLnRrv] [-A addr_family] [-c traffic_class]
[-g gateway [-g gateway ...]] [-F flow_label] [-I interval]
[-i interface] [-P tos] [-p port] [-t ttl] host [data_size] [npackets]

Good catch Stefan!


HTH,

p5wizard

 

[feherke]

Hi

Actually not only. But while I worked on an longer answer including a example script for the suggested [tt]pingw[/tt] function, Stefan already posted his question.

Hmm... I should change my style. Long answers works well only on mailing lists with daily digest delivery.

Feherke.

http://rootshell.be/~feherke/

 

[viadisky]

Hi Feherke,

The suggestion you provided (introducing the function) is quite interesting.Can you recommend some reading materials on this topic? I would like to increase my level of knowledge but it somehow confusing where to start ...

Maria

 

[feherke]

Hi

Sorry, I have nothing special to recommend, mostly I only read the man pages. And some one-liner collections, which are simple but full of tricks.

http://google.com/search?q=sed+OR+awk+one-liner

Feherke.

http://rootshell.be/~feherke/