Question about DAI, Thanks.

Unanswered Question
May 16th, 2010
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I asked a question here, but still not clearly about something.

I found a document said the DAI only detect a single swith,that means I must do DAI on all the switch in my Lan?

for example:

I have 2 PC and none DHCP environment.
in switch access A,i do DAI with arp access-list for PC A;
in switch access B,i do DAI with arp access-list for PC B;
in switch core A,i do DAI with arp access-list for PC A and PC B;

if there is a lot of PC in my LAN,the work in core A is so complex,I must do DAI with arp access-list with all PCs in my Lan,that is a lot of work to do!!!

I don't know whether my description is right,what do you think about it?
thanks alot.

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Jon Marshall Sun, 05/16/2010 - 09:17
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You only need to use arp access-lists if you are using DAI in non-DHCP environments. If your PCs obtain their IP addresses via DHCP then you don't need to write arp acls for each device. You also need to enable DHCP snooping if you are using DHCP for your client IP addresses.

See this link for full details -

3750 DAI



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