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Re: ip gratuitous-arps [7:79996] posted 12/02/2003
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Yes, and also if the router ever receives an ARP packet that tries to 
overwrite the IP owned by the router it will send a gratuitous arp.

This was in response to:
http://www.cisco.com/warp/public/707/IOS-arp-overwrite-vuln-pub.shtml

hth



Priscilla Oppenheimer wrote:

> =?iso-8859-1?q?Gerard=20Torin?= wrote:
> 
>>Hi Guys, anybody know how I`ll see if gratuitous-arps is enable
>>on the Cisco Routers?
> 
> 
> Cisco routers do use gratuitous ARP and I don't think it's configurable, so
> you won't see it in the configuration file. If you want to see it in
action,
> use a sniffer while a router is booting. You'll see something like the
> following from one of my routers:
> 
> Ethernet Header
>   Destination:          FF:FF:FF:FF:FF:FF  Ethernet Broadcast
>   Source:               00:00:0C:3F:00:D4
>   Protocol Type:        0x0806  IP ARP
> ARP - Address Resolution Protocol
>   Hardware:             1  Ethernet (10Mb)
>   Protocol:             0x0800  IP
>   Hardware Address Length:6
>   Protocol Address Length:4
>   Operation:            2  ARP Response
>   Sender Hardware Address:00:00:0C:3F:00:D4
>   Sender Internet Address:172.16.10.1
>   Target Hardware Address:FF:FF:FF:FF:FF:FF  Ethernet Broadcast
>   Target Internet Address:172.16.10.1
> Extra bytes
>   Number of bytes:
>   ................  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>   ..                00 00
> FCS - Frame Check Sequence
>   FCS (Calculated):     0xE7459D04 
> 
> Priscilla
> 
> 
> 
>> 
>>Thanks for you help!!!!
>>
>>
>>---------------------------------
>>Yahoo! Sorteos
>>!Ya puedes comprar Loterma de Navidad!
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Message Posted at:
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