DHCP Options

When sending DHCP requests, additional options can be requested by providing a space separated list of codes.

Code Description
0 Pad.
1 Subnet Mask.
2 Time Offset(deprecated).
3 Router.
4 Time Server.
5 Name Server.
6 Domain Name Server.
7 Log Server.
8 Quote Server.
9 LPR Server.
10 Impress Server.
11 Resource Location Server.
12 Host Name.
13 Boot File Size.
14 Merit Dump File.
15 Domain Name.
16 Swap Server.
17 Root Path.
18 Extensions Path.
19 IP Forwarding enable/disable.
20 Non-local Source Routing enable/disable.
21 Policy Filter.
22 Maximum Datagram Reassembly Size.
23 Default IP Time-to-live.
24 Path MTU Aging Timeout.
25 Path MTU Plateau Table.
26 Interface MTU.
27 All Subnets are Local.
28 Broadcast Address.
29 Perform Mask Discovery.
30 Mask supplier.
31 Perform router discovery.
32 Router solicitation address.
33 Static routing table.
34 Trailer encapsulation.
35 ARP cache timeout.
36 Ethernet encapsulation.
37 Default TCP TTL.
38 TCP keepalive interval.
39 TCP keepalive garbage.
40 Network Information Service Domain.
41 Network Information Servers.
42 NTP servers.
43 Vendor specific information.
44 NetBIOS over TCP/IP name server.
45 NetBIOS over TCP/IP Datagram Distribution Server.
46 NetBIOS over TCP/IP Node Type.
47 NetBIOS over TCP/IP Scope.
48 X Window System Font Server.
49 X Window System Display Manager.
50 Requested IP Address.
51 IP address lease time.
52 Option overload.
53 DHCP message type.
54 Server identifier.
55 Parameter request list.
56 Message.
57 Maximum DHCP message size.
58 Renew time value.
59 Rebinding time value.
60 Class-identifier.
61 Client-identifier.
62 NetWare/IP Domain Name.
63 NetWare/IP information.
64 Network Information Service+ Domain.
65 Network Information Service+ Servers.
66 TFTP server name.
67 Bootfile name.
68 Mobile IP Home Agent.
69 Simple Mail Transport Protocol Server.
70 Post Office Protocol Server.
71 Network News Transport Protocol Server.
72 Default World Wide Web Server.
73 Default Finger Server.
74 Default Internet Relay Chat Server.
75 StreetTalk Server.
76 StreetTalk Directory Assistance Server.
77 User Class Information.
78 SLP Directory Agent.
79 SLP Service Scope.
80 Rapid Commit.
81 FQDN, Fully Qualified Domain Name.
82 Relay Agent Information.
83 Internet Storage Name Service.
84 N/A
85 NDS servers.
86 NDS tree name.
87 NDS context.
88 BCMCS Controller Domain Name list.
89 BCMCS Controller IPv4 address list.
90 Authentication.
91 Client-last-transaction-time.
92 Associated-ip.
93 Client System Architecture Type.
94 Client Network Interface Identifier.
95 LDAP, Lightweight Directory Access Protocol.
96 N/A
97 Client Machine Identifier.
98 Open Group's User Authentication.
99 GEOCONF_CIVIC.
100 IEEE 1003.1 TZ String.
101 Reference to the TZ Database.
102-111 N/A
112 NetInfo Parent Server Address.
113 NetInfo Parent Server Tag.
114 URL.
115 N/A
116 Auto-Configure
117 Name Service Search.
118 Subnet Selection.
119 DNS domain search list.
120 SIP Servers DHCP Option.
121 Classless Static Route Option.
122 CCC, CableLabs Client Configuration.
123 GeoConf.
124 Vendor-Identifying Vendor Class.
125 Vendor-Identifying Vendor-Specific.
126 - 127 N/A
128 TFPT Server IP address.
129 Call Server IP address.
130 Discrimination string.
131 Remote statistics server IP address.
132 802.1P VLAN ID.
133 802.1Q L2 Priority.
134 Diffserv Code Point.
135 HTTP Proxy for phone-specific applications.
136 PANAAuthentication Agent.
137 LoSTServer.
138 CAPWAP Access Controller addresses.
139 OPTION-IPv4_Address-MoS.
140 OPTION-IPv4_FQDN-MoS.
141 SIP UA Configuration Service Domains.
142 OPTION-IPv4_Address-ANDSF.
143 OPTION-IPv6_Address-ANDSF.
144 - 149 N/A
150 TFTP server address.
150 Ether boot. GRUB configuration path name.
151-174 N/A
175 Ether boot.
176 IP Telephone.
177 Ether boot. Packet Cable and Cable Home.
178- 207 N/A
208 pxelinux.magic (string) = F1:00:74:7E (241.0.116.126).
209 pxelinux.configfile (text).
210 pxelinux.pathprefix (text).
211 pxelinux.reboottime (unsigned integer 32 bits).
212 OPTION_6RD.
213 OPTION_V4_ACCESS_DOMAIN.
214-219 N/A
220 Subnet Allocation.
221 Virtual Subnet Selection.
222-223 N/A
224-254 Private use.
255 End.