Cisco IOS switch dropping legit DHCP requests

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http://serverfault.com – We have Cisco Catalyst 4507R running IOS v12.2 that appears to be dropping valid DHCP requests. Checking for the requests using tcpdump on the DHCP server and on a machine connected to a monitoring port shows that only after 30s (and on the 8th request) does the request make it to the server. The request packets appear to not have any indicators that would trigger the DHCP control features on the switch that I know of, and are from uBoot doing a network boot (but also show when other machines are booting) Below is the DHCP snooping config on the switch, I do notice that the restrictions on h (HowTos)