In some circumstance, the system may display the following log information:
%Apr 3 15:41:09 2006 JMSDX_MEIJIANG_S9512 DHCPR/4/invalidpkt:
Wrong BOOTP packet!
This log information implies that S9500 has received illegal DHCP packets. However, the information may also be displayed in devices with no DHCP enabled and cause misunderstanding in users. This case is due to S9500 mechanism.
The processing mechanism of S9500 is to check a packet’s validity and allocate the corresponding software module accordingly. If the corresponding function is not enabled, the packet is dropped directly.
The problem may happen in the following occasions:
1. DHCP packet check-sum is incorrect. DHCP packet has a special field Magic Cookie for checking whether the packet is correct.
2. DHCP packet type is incorrect, namely, it is neither relay packet nor request packet.
3. DHCP packet broadcast flag is incorrect. The packet should have non-zero value only for the highest bit, and zero value for all other bits.
4. The gateway address of the DHCP packet is not of ABC type after relay.