problem with dhcp on 2960 switches

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Hi All

I need your help

We have a dhcp server that was connected to Cisco 2960 which in turn was
connected to alcatel switches, all worked fine. we changed the alcatel
switches to cisco 2960's. We now have a problem that only devices directly
connected to the original 2960(where the dhcp server is connected to) is
receiving IP addresses we have now 4 other 2960's onthe network but we
cannot get a IP address when we connect to any of the ports. doing a sniffer
trace on the working switch the DHCP four way handshake is performed,
discovery>>offer>>request>>>ack

On one of the other switches only the discovery is seen but no offer
response from the dhcp server is seen therefore no ip address is received.
the new switches only have portfast set and an ip address for vlan1 so I
cannot understand what is stopping the dhcp traffic

Any  Ideas

Thanks

Simon



Re: problem with dhcp on 2960 switches
Simon,

Check for "DHCP Snooping" on both switches. Basically, just do a "show run |
inc dhcp". If you have DHCP Snooping implemented, configure uplink as a
"trusted port".

Good luck,

Mike
CCNP, CCDP, CCSP, Cisco Voice, MCSE W2K, MCSE+I, Security+, etc.
CCIE R&S (in progress), CCIE Voice (in progress)
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Re: problem with dhcp on 2960 switches
I havn't got DHCP snooping configured on any of the switches


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