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I have an interface that I can arping to by its IP, but not its MAC address:

# arping -i eth2 10.10.0.153
ARPING 10.10.0.153
60 bytes from 02:68:b3:29:da:98 (10.10.0.153): index=0 time=81.062 usec
60 bytes from 02:68:b3:29:da:98 (10.10.0.153): index=1 time=46.968 usec
60 bytes from 02:68:b3:29:da:98 (10.10.0.153): index=2 time=73.910 usec
60 bytes from 02:68:b3:29:da:98 (10.10.0.153): index=3 time=46.968 usec

# arping -i eth2 02:68:b3:29:da:98
ARPING 02:68:b3:29:da:98
(no reply)

I don't have this problem with other interfaces on my network. What are the possible issues that could cause this?

I'm running on Ubuntu 12.04.

Lorin Hochstein
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1 Answers1

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arping -i eth2 10.10.0.153

Send out an ARP packet asking, "Who has the IP 10.10.0.153?"

arping -i eth2 02:68:b3:29:da:98

Sends out an IPv4 ping to the IP address 255.255.255.255 with the target MAC of 02:68:b3:29:da:98.

It is common nowadays to disable responding to broadcast pings. On a Linux system (well any, but I'm only providing a link for one), you can re-enable replies to broadcast IP addresses.

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Jeff Ferland
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  • I do see outbound packets when pinging against a MAC, if I do this: `tcpdump -ennqti eth2 \( arp or icmp \)`. I just don't see any come back. – Lorin Hochstein Mar 12 '13 at 01:58
  • Oops, I messed up my filters. Let me post a new one with the right answer now that I realize what happened. – Jeff Ferland Mar 12 '13 at 02:00