How to ping and return only the IP address?

guest · 05-04-2009, 11:26 PM

Is there a simple way to return an IP by pinging a hostname? Ideally it takes low resources because I have a lot of hostnames to ping!

Thanks in advance

billymayday · 05-04-2009, 11:50 PM

Is your objective to determine the IP, because if so, you should relly use a tool devised for that task such as nslookup or dig. That said, pinging a hostname will normally return an IP, so I don't quite see what you are asking.

guest · 05-05-2009, 12:03 AM

I'd like a command that returns ONLY the IP, so something that parses the mumbo jumbo results and outputs only:
1.2.3.4

Is what I'm asking for

Neminath · 05-05-2009, 01:00 AM

You can use nmap it has nice features for ping scan of network
it gives lot of other information but u can use a simple perl script to filter out what u want

ghostdog74 · 05-05-2009, 01:25 AM

if you have and know Python and able to use it

Code:

#!/usr/bin/env python
import socket
for hosts in open("file"):
    hosts=hosts.strip()
    try:
        print "doing ",hosts,socket.gethostbyname(hosts)
    except Exception,e:
        print e

output:

Code:

# more file
www.google.com
www.abc.com
www.test.com
localhost
# ./test.py
doing  www.google.com 216.239.61.104
doing  www.abc.com 199.181.132.250
doing  www.test.com 205.178.152.103
doing  localhost 127.0.0.1

guest · 05-05-2009, 01:39 AM

Hmm.. i'm sure there's an awk or sed one liner.. or perl 1 liner to get this done.. that looks like it could be server intensive..

guest · 05-05-2009, 02:10 AM

for example:
ping -n -q -c1 yahoo.com |grep '(' | egrep -o '[0-9.]+'

but it's returning:
.
209.191.93.53
56
84
.

I just need the:
209.191.93.53

ghostdog74 · 05-05-2009, 02:39 AM

Quote:

Originally Posted by guest

that looks like it could be server intensive..

definitely not.

billymayday · 05-05-2009, 03:55 AM

Try

dig +short www.example.com | sed -e '1d'

This will still give you multiple IPs where valid (for example, www.google.com)

theNbomr · 05-05-2009, 09:59 AM

A one-liner that depends on the format of the reply from ping:

Code:

ping -c 1 some.ip.name | perl -e '$header=<>;$header=~m/ \(([^)]+)\) /;print $1;'

Tested on RHEL4.
--- rod.

vikas027 · 05-05-2009, 10:10 AM

Quote:

Originally Posted by guest

Hmm.. i'm sure there's an awk or sed one liner.. or perl 1 liner to get this done.. that looks like it could be server intensive..

Another, one liner.

Make a file called list contains all hostnames.

and run this

Code:

for i in `cat list`;
do
ping -c 1 $i | head -1 | awk -F "(" '{print $2}' | awk -F ")" '{print $1}'
done;

Tested on RHEL3 and RHEL4

Sergei Steshenko · 05-05-2009, 10:40 AM

'host' anyone ?

Code:

host yahoo.com
yahoo.com has address 69.147.114.224
yahoo.com has address 209.191.93.53
yahoo.com has address 209.131.36.159
yahoo.com mail is handled by 1 c.mx.mail.yahoo.com.
yahoo.com mail is handled by 1 d.mx.mail.yahoo.com.
yahoo.com mail is handled by 1 e.mx.mail.yahoo.com.
yahoo.com mail is handled by 1 f.mx.mail.yahoo.com.
yahoo.com mail is handled by 1 g.mx.mail.yahoo.com.
yahoo.com mail is handled by 1 a.mx.mail.yahoo.com.
yahoo.com mail is handled by 1 b.mx.mail.yahoo.com.

One can't expect just one IP address.

ghostdog74 · 05-05-2009, 07:40 PM

Quote:

Originally Posted by vikas027

Another, one liner.

Make a file called list contains all hostnames.

and run this

Code:

for i in `cat list`;
do
ping -c 1 $i | head -1 | awk -F "(" '{print $2}' | awk -F ")" '{print $1}'
done;

Tested on RHEL3 and RHEL4

no need that much piping

Code:

ping -c 1 $i | awk 'NR==1{gsub(/\(|\)/,"",$3);print $3}'

vikas027 · 05-07-2009, 11:46 AM

Quote:

Originally Posted by ghostdog74

no need that much piping

Code:

ping -c 1 $i | awk 'NR==1{gsub(/\(|\)/,"",$3);print $3}'

Hi ghostdog, I am not very expert in scripting. I know my codes are not optimized But yes I can make things work. I know what I do in 4-5 lines is very much possible in single line by might utilities like sed/awk... I am still in process of learning

Could you please explain the awk line you used here ?

Thanks in adv.

Sergei Steshenko · 05-07-2009, 02:06 PM

Why does IP address has to be returned through 'ping' in the first place ? I.e. why not to resolve hosts without 'ping' ?