DHCP request, ack, inform, inform at boot?
Just to see what was happening when a computer reboots and has been assigned an IP by DHCP, I reset the PC described earlier (i.e., 192.168.1.34). I expected no activity so was surprised to sniff 4 packets, 3 from the PC. It was a REQUEST packet from the PC, followed within 5/1000th of a second by an ACK. Over a minute later, the PC issued and INFORM packet and another 3 seconds later.
I’m going to put the sniffer on for DHCP packets and, if I can figure out how, for PING packets, too.
Update: Use Ethereal’s capture filter using the expression:
port 67 or port 68 or icmp