> On Wed, Sep 15, 2004 at 12:35:41PM -0000, Dion wrote: >> Setahu saya dhcpd ngga broadcast apa apa in regards to dhcp protocol. >> client yang broadcast DHCPDISCOVER ke servers. > > DHCP itu menggunakan UDP packets, jadi layer 3. Gimana caranya layer 3 > packets yg dikirim oleh server bisa mencapai si client yg belum punya > layer 3 address? Broadcast.
Unicast langsung ke MAC address, hanya jika client set broadcast bit waktu request, server akan broadcast. kutipan dari ftp://ftp.rfc-editor.org/in-notes/rfc2131.txt In the case of a client using DHCP for initial configuration (before the client's TCP/IP software has been completely configured), DHCP requires creative use of the client's TCP/IP software and liberal interpretation of RFC 1122. The TCP/IP software SHOULD accept and forward to the IP layer any IP packets delivered to the client's hardware address before the IP address is configured; DHCP servers and BOOTP relay agents may not be able to deliver DHCP messages to clients that cannot accept hardware unicast datagrams before the TCP/IP software is configured. To work around some clients that cannot accept IP unicast datagrams before the TCP/IP software is configured as discussed in the previous paragraph, DHCP uses the 'flags' field [21]. The leftmost bit is defined as the BROADCAST (B) flag. The semantics of this flag are discussed in section 4.1 of this document. The remaining bits of the flags field are reserved for future use. They MUST be set to zero by clients and ignored by servers and relay agents. Figure 2 gives the format of the 'flags' field. Ini log isc dhcpd, client adalah linux 14:50:24.413529 00:0a:cd:01:7e:81 > ff:ff:ff:ff:ff:ff, ethertype IPv4, length 342: IP (tos 0x10, ttl 16, id 0, offset 0, flags [none], length: 328) 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request [|bootp] 14:50:25.000850 00:0a:cd:05:63:df > 00:0a:cd:01:7e:81, ethertype IPv4, length 370: IP (tos 0x10, ttl 16, id 0, offset 0, flags [none], length: 356) 192.168.10.195.67 > 192.168.10.245.68: BOOTP/DHCP, Reply, length: 328, xid:0x638b3201, flags: [none] Your IP: 192.168.10.245 Server IP: 192.168.10.195 [|bootp] 14:50:25.001212 00:0a:cd:01:7e:81 > ff:ff:ff:ff:ff:ff, ethertype IPv4, length 590: IP (tos 0x10, ttl 16, id 0, offset 0, flags [none], length: 576) 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request [|bootp] 14:50:25.001788 00:0a:cd:05:63:df > 00:0a:cd:01:7e:81, ethertype IPv4, length 359: IP (tos 0x10, ttl 16, id 0, offset 0, flags [none], length: 345) 192.168.10.195.67 > 192.168.10.245.68: BOOTP/DHCP, Reply, length: 317, xid:0x648b3201, flags: [none] Your IP: 192.168.10.245 Server IP: 192.168.10.195 [|bootp] 14:50:25.002107 00:0a:cd:01:7e:81 > ff:ff:ff:ff:ff:ff, ethertype IPv4, length 590: IP (tos 0x10, ttl 16, id 0, offset 0, flags [none], length: 576) 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request [|bootp] 14:50:25.005204 00:0a:cd:05:63:df > 00:0a:cd:01:7e:81, ethertype IPv4, length 359: IP (tos 0x10, ttl 16, id 0, offset 0, flags [none], length: 345) 192.168.10.195.67 > 192.168.10.245.68: BOOTP/DHCP, Reply, length: 317, xid:0x658b3201, flags: [none] Your IP: 192.168.10.245 Server IP: 192.168.10.195 [|bootp] -- Unsubscribe: kirim email kosong ke [EMAIL PROTECTED] Arsip, FAQ, dan info milis di http://linux.or.id/milis.php Tidak bisa posting? Baca: http://linux.or.id/wiki/index.php?pagename=ProblemMilisDanSolusi http://linux.or.id/wiki/index.php?pagename=TataTertibMilis
