On 23/11/2007, 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 <chloekcy2000@xxxxxxxx> 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 <cs@xxxxxxxxxx> DoD#743 > http://www.cskk.ezoshosting.com/cs/ To make matters worse, a system may be up but firewalls may block pings. Kind regards, Herta -- redhat-list mailing list unsubscribe mailto:redhat-list-request@xxxxxxxxxx?subject=unsubscribe https://www.redhat.com/mailman/listinfo/redhat-list
