Some additional information regarding DHCP..... As I mentioned, the lease information is retained by both the client and the server..... Let's assume that this is not the first time the client has acquired an IP address from the server. Let's also assume that the interface is currently down and a file exists in /var/lib/dhcpclient for the interface in question. Now, you enable the interface and the following happens.... 1. The dhcpclient checks the file to see what IP address it was last assigned. 2. The client then sends out a UDP broadcast with source address of 0.0.0.0 and destination of 255.255.255.255 (a broadcast request) It will be a message type of DHCP Request and the packet will contain the previous IP address it is requesting. It will also have a "transaction ID" in the packet. 3. The server will respond. The source address will be its IP address and the destination will be 255.255.255.255 Another broadcast. The response will have the same "transaction ID" as the request and the client will match these to know the broadcast message is meant for it. You are done.... If a file in /var/lib/dhcpclient does not exist for the interface the procedure is a bit different.... 1. The client sends out a DHCP Discover. 2. The server sends out a DHCP offer. Offering an IP address to the client. If the server had issued a lease in the past to this MAC address it *may* offer the same IP address. 3. The client sends out a DHCP Request as in #2 above. 4. The server sends out a DHCP ACK as in #3 above. FWIW, a DHCP request can request quite a bit of information that the server may or may not supply. Some examples would be.... Subnet Mask Broadcast Address Domain Name Domain Name Server NIS Domain NTP Servers -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
