Missing ARP Entries in  CATOS

Posted on 2007-08-01
Last Modified: 2011-09-20
my Cisco 4006 SUP II only show entries in ARP after I connect to the switch via telnet.  It will only have entries in ARP for the computers that I have used to telnet into the SUP.  The switch appears to be working fine as all the computers can talk to each other.  Why would the table not show entries for all devices?


Console> (enable) sh arp
ARP Aging time = 1200 sec
+ - Permanent Arp Entries
* - Static Arp Entries                             at 00-11-11-ee-39-91 port  2/10 on vlan 1                             at 00-11-11-ee-3f-05 port  2/3 on vlan 1
Question by:sean-keys
    1 Comment
    LVL 50

    Accepted Solution

    Because the ARP cache of the supervisor is ONLY used when the supervisor communicates with a device. It is not used to pass traffic. The CAM table is all that is needed to forward traffic.

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