find all active IP addresses in a network

ping -c2 >/dev/null; arp -a

2010-04-11 15:29:08

What Others Think

You can't find "all" active IP addresses in a network this way. Many (most?) operating systems will ignore broadcast ping packets by default, for security reasons. Apart from that, it is customary to deny broadcast ping packets in firewall and packet filter configurations.
inof · 659 weeks and 6 days ago
What's dangerous about pinging your broadcast address? It populates your arp table so you find the MAC addresses of devices on your network.
putnamhill · 563 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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