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Problem with DHCP snooping\IPSG

Hello everyone.

 

Have problem with IP Source Guard feature.

Host connecting to network and had ip from DHCP MS server, lease time at first is 1 hour, after about 30min host request additional lease and get lease time - 7 day.

DHCP snooping switched on. When host ask dhcp for the first time, there is an entry in switch snooping base with right lease time 1 hour, but when host ask additional lease, snooping base isnt updating lease time and, when 1hour lease over, IPSG switched on interface.

Problem appears on a few hosts on switch, it isnt global problem. TCP dump from host shows packets with additional dhcp request(after 30 min).

Why switch ignoring additional DHCP packets?

Cat4510R

image cat4500e-universalk9.SPA.03.08.09.E.152-4.E9.bin

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VIP Mentor

Re: Problem with DHCP snooping\IPSG

Hello

Is your IPSG active for ip or ip & mac addressing?

Is there any difference between those puts that are not working correctly and the other ports that do?

Do you have spanning-port fast enabled on the access ports?



kind regards
Paul

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VIP Collaborator

Re: Problem with DHCP snooping\IPSG

Hello,

it is possible to share the current configuration?
Jaderson Pessoa
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