Proxy arp (how to add an arp entry)

Proxy arp (how to add an arp entry)

Post by Pete Bre » Thu, 09 May 2002 18:19:00

I am trying to use proxy arp to isolate a portion of a network to reduce
traffic. When I use the arp program with the following syntax to add an entry

arp -v -i eth0 -s {IP address} {Mac address} pub

and then look at the arp table, the flags against this new entry are MP (no C
flag to indicate that the entry is complete). The HWtype and HWaddress columns
both have * in them. If I try to ping {IP address} from another machine whilst
watching the arp traffic with tcpdump, I see the arp requests, but no arp
If I use the same command line, but without the pub keyword, then the entry is
added successfully... HWtype set to ether, HWaddress set correctly and flags set
to CM.
What am I doing wrong? How should I change my command line to complete the entry
in the arp table? Is there an option which needs to be set when compiling the
kernel to allow arp to add entries with the public flag set?

Incase it is relevant,
Distribution:   Redhat 6.0
Kernel:         2.2.5-15
arp version:    1.85



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Can someone tell me how to remove a entry in the arp.dat that DOES NOT have
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As well is there a way to block the arp from accepting any ip's other than a
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Any help is greatly appreciated,
Thanks Dean!

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