Scan network for IP addresses

What is the CL syntax for scanning my LAN and listing the active IP
addresses?
I am using Ubuntu 8.10 on the servers and my desktop.

Zoomiest wrote:

> What is the CL syntax for scanning my LAN and listing the active IP
> addresses?
> I am using Ubuntu 8.10 on the servers and my desktop.

Google for nmap

On Sat, 28 Mar 2009 06:57:33 -0700, Zoomiest wrote:

> What is the CL syntax for scanning my LAN and listing the active IP
> addresses?
> I am using Ubuntu 8.10 on the servers and my desktop.

nmap -sP 192.168.1.*

Substitute whatever network numbering scheme you are using on the LAN...


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"Ubuntu" -- an African word, meaning "Slackware is too hard for me".
Need help?: http://brandybuck.site40.net/pics/ubuntu.jpg
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On Mar 28, 2:48*pm, Dan C <youmustbejok...@lan.invalid> wrote:
> On Sat, 28 Mar 2009 06:57:33 -0700, Zoomiest wrote:
> > What is the CL syntax for scanning my LAN and listing the active IP
> > addresses?
> > I am using Ubuntu 8.10 on the servers and my desktop.
>
> nmap -sP 192.168.1.*
>
> Substitute whatever network numbering scheme you are using on the LAN...
>
> --
> "Ubuntu" -- an African word, meaning "Slackware is too hard for me".
> Need help?: *http://brandybuck.site40.net/pics/ubuntu.jpg
> The Usenet Improvement Project:http://improve-usenet.org
> Ahhhhhhhh!: *http://brandybuck.site40.net/pics/relieve.jpg

Hi, i think if you have firewall on your lan's pc that maybe you
should use "arping", i don't known if you can,as for nmap, define a
network scheme, i usually use a script for pass ip addresses to
arping.

Maxwell Lol <(E-Mail Removed)> wrote:

> ping -b 192.168.1.255 (or whatever the broadcast address)

Hmmm, that sounded interesting, but I tried it here and absolutely nothing
replied.

Mark.

--
Mark Hobley
Linux User: #370818 http://markhobley.yi.org/

On Mon, 30 Mar 2009 07:27:25 -0400, Maxwell Lol wrote:
> (E-Mail Removed) (Mark Hobley) writes:
>
>> Maxwell Lol <(E-Mail Removed)> wrote:
>>
>>> ping -b 192.168.1.255 (or whatever the broadcast address)
>>
>> Hmmm, that sounded interesting, but I tried it here and absolutely nothing
>> replied.
>
> It worked for me. You might have to be superuser, and you have to get
> the broadcast address correct.

Winderz boxen do not respond to flood pinging -- atleast XP doesn't.

Maxwell Lol wrote:
> (E-Mail Removed) (Mark Hobley) writes:
>
>> Maxwell Lol <(E-Mail Removed)> wrote:
>>
>>> ping -b 192.168.1.255 (or whatever the broadcast address)
>> Hmmm, that sounded interesting, but I tried it here and absolutely nothing
>> replied.
>
> It worked for me. You might have to be superuser, and you have to get
> the broadcast address correct.
>
> As the manual page says
>
> Flood pinging is not recommended in general, and flood pinging the
> broadcast address should only be done under very controlled condi�
> tions.
>
> So there may be a policy of some sort (in the source code?) to disable this.

-b is broadcast ping, not flood ping. Many (most?) systems ignore broadcast
pings these days.

Maxwell Lol <(E-Mail Removed)> writes:

> (E-Mail Removed) (Mark Hobley) writes:
>
>> Maxwell Lol <(E-Mail Removed)> wrote:
>>
>>> ping -b 192.168.1.255 (or whatever the broadcast address)
>>
>> Hmmm, that sounded interesting, but I tried it here and absolutely nothing
>> replied.
>
> It worked for me. You might have to be superuser, and you have to get
> the broadcast address correct.
>
> As the manual page says
>
> Flood pinging is not recommended in general, and flood pinging the
> broadcast address should only be done under very controlled condi�
> tions.
>
> So there may be a policy of some sort (in the source code?) to disable this.

/proc/sys/net/ipv4/icmp_echo_ignore_broadcasts -- if it's 0 you
respond to broadcast pings, if it's 1 you don't. By default (on my
debian boxes) it's 1.

So, depending on what the OP is really trying to do, this isn't
something he can rely on.

On 2009-03-30, Mark Hobley <(E-Mail Removed)> wrote:
> Maxwell Lol <(E-Mail Removed)> wrote:
>
>> ping -b 192.168.1.255 (or whatever the broadcast address)
>
> Hmmm, that sounded interesting, but I tried it here and absolutely nothing
> replied.

ICMP settings
-------------

icmp_echo_ignore_all and icmp_echo_ignore_broadcasts
----------------------------------------------------

Turn on (1) or off (0), if the kernel should ignore all ICMP
ECHO requests, or just those to broadcast and multicast addresses.

Please note that if you accept ICMP echo requests with a
broadcast/multi\-cast destination address your network may
be used as an exploder for denial of service packet flooding
attacks to other hosts.

{53622:68} [0:0]$ cat /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts
1


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Torvalds' goal for Linux is very simple: World Domination
Stallman's goal for GNU is even simpler: Freedom

On 3$B7n(B30$BF|(B, $B8aA0(B4:35, Maxwell Lol <nos...@com.invalid> wrote:
> Zoomiest <zoomi...@gmail.com> writes:
> > What is the CL syntax for scanning my LAN and listing the active IP
> > addresses?
> > I am using Ubuntu 8.10 on the servers and my desktop.
>
> Besides nmap, you might be able to do
> ping -b 192.168.1.255 (or whatever the broadcast address)


you can find host whose firewall is on with nmap,but ping can not do
this