Thank you how to use dns lookups thank you again "Broekman, Maarten" <Maarten.Broekman@xxxxxxx> wrote: Why not just do DNS lookups to see which ones are assigned? To build on what Cameron mentioned, just put in "host $i" in the loop and check to see it returns anything sane. If so, you might want to ping it to see if it's up, but as Cameron said, the system could be down or off so that's not 100% reliable. Maarten Broekman Email: maarten.broekman@xxxxxxx -----Original Message----- From: redhat-list-bounces@xxxxxxxxxx [mailto:redhat-list-bounces@xxxxxxxxxx] On Behalf Of Cameron Simpson Sent: Thursday, November 22, 2007 4:10 PM To: General Red Hat Linux discussion list Subject: Re: script or other suggestion On 22Nov2007 15:35, chloe K wrote: | I have ip list in my network | I need to check which ip is unused | what is better solution? | | Write the ping script or use other command | | eg: | | for i in ip.txt | ping -c 3 $i That would be: for i in `cat ip.txt` do ping -c 3 $i || { echo "IP $i is not in use."; break; } done Of course, if a machine happens to be down/off, if will look like its IP is not in use... You could possibly do something clever with nmap or "ping -b", but your approach is simple and effective. -- Cameron Simpson DoD#743 http://www.cskk.ezoshosting.com/cs/ Getting a SCSI chain working is perfectly simple if you remember that there must be exactly three terminations: one on one end of the cable, one on the far end, and the goat, terminated over the SCSI chain with a silver-handled knife whilst burning *black* candles. - Anthony DeBoer -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list --------------------------------- Instant message from any web browser! Try the new Yahoo! Canada Messenger for the Web BETA -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
