Gratuitous ARP problem

[cleetusant]

Hi,

My Cisco 3750 Catalyst switch is my DHCP server and sometimes all clients getting issues of not getting IP address and when I check the show ip dhcp-conflicts, it shows there will be plenty of gratuitous APR request entry associated to an IP address and a mac address. Due to which the dhcp scope is  fully utilized. When I clear ip dhp conflict* , things will be normal. How to prevent it.

Regards

Cleetus   

[a.alekseev · Accepted solution]

no ip dhcp conflict logging

[a.alekseev · Accepted solution]

https://blog.ipspace.net/2007/08/dhcp-conflict-logging-true-story.html

[balaji.bandi]

Can you post some output when the problem exists :

show ip dhcp conflict
show ip dhcp pool

How many devices  in the network for that pool, make sure you have enough IP in that range.

BB

[cleetusant]

as mentioned in my post, "show ip dhcp conflict" shows many lines of Gratuitous ARP entry with mac address and Ip address.

"show ip dhcp pool "  shows 0.0.0.0 as current index. which means there is no more address left for clients. So I clear the dhcp conflicts and thus I get enough addresses.