How to get all arp entries for a certain network

Hi,
How can I get my arp table to fill up with all the objects in a
certain network(which I have the network/netmask). The only way I
found is pinging all the objects in the network one by one....I know
there's a better way. Using redhat , perl solutions are welcome !
10x in advance

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
NotDashEscaped: You need GnuPG to verify this message

In comp.os.linux.networking Zahi Shahak <(E-Mail Removed)> suggested:
> Hi,
> How can I get my arp table to fill up with all the objects in a
> certain network(which I have the network/netmask). The only way I
> found is pinging all the objects in the network one by one....I know
> there's a better way. Using redhat , perl solutions are welcome !
> 10x in advance

man ping
/-b

--
Michael Heiming (GPG-Key ID: 0xEDD27B94)
mail: echo (E-Mail Removed) | perl -pe 'y/a-z/n-za-m/'
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.4 (GNU/Linux)

iD8DBQFBN2EZAkPEju3Se5QRAgTvAJ4udgrTscXPr7Pb08qhX4 KdGuwS7ACeO+XX
7ZQ6PxVOA8KtA7ipx0JOVAE=
=ZTC2
-----END PGP SIGNATURE-----

Zahi Shahak wrote:

> Hi,
> How can I get my arp table to fill up with all the objects in a
> certain network(which I have the network/netmask). The only way I
> found is pinging all the objects in the network one by one....I know
> there's a better way. Using redhat , perl solutions are welcome !
> 10x in advance

You can do a broadcast ping, to the broadcast address.

--

(This space intentionally left blank)

In article <(E-Mail Removed)> , Zahi Shahak wrote:
>Hi,
>How can I get my arp table to fill up with all the objects in a
>certain network(which I have the network/netmask). The only way I
>found is pinging all the objects in the network one by one....I know
>there's a better way.

Ping the broadcast (ping -b), but don't do this very much, as it can
generate a lot of traffic. And remember:

1. Some hosts will not respond to a broadcast ping, though they _will_
respond to a unicast ping (to their speciifc address).

2. Some hosts have firewalls configured to block/ignore pings.

A less invasive technique is to just run a sniffer like tcpdump
looking for ARP request/reply packets. I used to run an application
that monitored the ARP cache of the routers and DNS servers (then
comparing the results with a data base to detect "unusual" events)
for security purposes. 'arpwatch' is somewhat similar in function.

Old guy