DHCP-Snooping bridge packet get invalid mat entry

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May 23rd, 2007
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Hi together,

i've configured dhcp-snooping and it seems to work by creating snooping-bindings but some laptops still don't get an ip address

wireshark says that there are only dhcp-requests and no offers/acks at the laptop

debugging on the switch gives the following output:

*May 23 08:03:36.824: DHCP_SNOOPING_SW: bridge packet get invalid mat entry: FFFF.FFFF.FFFF, packet is flooded to ingres

s VLAN: (104)

is somebody able to say what is happening here ?

thanks for your help

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didyap Wed, 05/30/2007 - 05:58
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As far as i understood this, this is normal. ffff.ffff.ffff isn't in the MAT table as it's the broadcast address.The packet is flooded to the Vlan, which is what you expect for a broadcast packet.

kulinski Wed, 05/30/2007 - 21:55
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yes, for sure..

but there is still the problem that laptops

can't get access to the network.

meanwhile i additionally configured "ip dhcp relay information trusted" not only at the physical interface(downlink to access-switch) but also at the svi at the distribution switch.

and now it works

but i'm still confused about the circumstance that normal pcs could get an ip-address while laptops couldn't.


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