Standard DHCP Options Defined in ISC DHCP and Kea
  • 30 May 2024
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Standard DHCP Options Defined in ISC DHCP and Kea

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Article summary

These tables show the standard options currrently defined for both DHCPv4 and DHCPv6 and which ones are supported in the ISC DHCP server and Kea DHCP servers.
They may be helpful in planning migration from one server to the other. If there is any doubt, the Kea User Guide includes two tables: supported standard options for DHCPv4 and DHCPv6. The tables below are meant to be a super-set of those.

DHCPv4 Options - updated 2024-01-26

code Name Reference DHCP Kea
0 Pad RFC 2132 Yes Yes
1 Subnet Mask RFC 2132 Yes Yes
2 Time Offset RFC 2132 Yes Yes
3 Router RFC 2132 Yes Yes
4 Time Server RFC 2132 Yes Yes
5 Name Server RFC 2132 Yes Yes
6 Domain Server RFC 2132 Yes Yes
7 Log Server RFC 2132 Yes Yes
8 Quotes Server RFC 2132 Yes Yes
9 LPR Server RFC 2132 Yes Yes
10 Impress Server RFC 2132 Yes Yes
11 RLP Server RFC 2132 Yes Yes
12 Hostname RFC 2132 Yes Yes
13 Boot File Size RFC 2132 Yes Yes
14 Merit Dump File RFC 2132 Yes Yes
15 Domain Name RFC 2132 Yes Yes
16 Swap Server RFC 2132 Yes Yes
17 Root Path RFC 2132 Yes Yes
18 Extension File RFC 2132 Yes Yes
19 Forward On/Off RFC 2132 Yes Yes
20 SrcRte? On/Off RFC 2132 Yes Yes
21 Policy Filter RFC 2132 Yes Yes
22 Max DG Assembly RFC 2132 Yes Yes
23 Default IP TTL RFC 2132 Yes Yes
24 MTU TImeout RFC 2132 Yes Yes
25 MTU Plateau RFC 2132 Yes Yes
26 MTU Interface RFC 2132 Yes Yes
27 MTU Subnet RFC 2132 Yes Yes
28 Broadcast Address RFC 2132 Yes Yes
29 Mask Discovery RFC 2132 Yes Yes
30 Mask Supplier RFC 2132 Yes Yes
31 Router Discovery RFC 2132 Yes Yes
32 Router Request RFC 2132 Yes Yes
33 Static Route RFC 2132 Yes Yes
34 Trailers RFC 2132 Yes Yes
35 ARP Timeout RFC 2132 Yes Yes
36 Ethernet RFC 2132 Yes Yes
37 Default TCP TTL RFC 2132 Yes Yes
38 Keepalive Time RFC 2132 Yes Yes
39 Keepalive Data RFC 2132 Yes Yes
40 NIS Domain RFC 2132 Yes Yes
41 NIS Servers RFC 2132 Yes Yes
42 NTP Servers RFC 2132 Yes Yes
43 Vendor Specific RFC 2132 Yes Yes
44 NETBIOS Name Srv RFC 2132 Yes Yes
45 NETBIOS Dist Srv RFC 2132 Yes Yes
46 NETBIOS Node Type RFC 2132 Yes Yes
47 NETBIOS Scope RFC 2132 Yes Yes
48 X Window Font RFC 2132 Yes Yes
49 X Window Manager RFC 2132 Yes Yes
50 Address Request RFC 2132 Yes Yes
51 Address Time RFC 2132 Yes Yes
52 Overload RFC 2132 Yes Yes
53 DHCP Msg Type RFC 2132 Yes Yes
54 DHCP Server ID RFC 2132 Yes Yes
55 Parameter List RFC 2132 Yes Yes
56 DHCP Message RFC 2132 Yes Yes
57 DHCP Max Msg Size RFC 2132 Yes Yes
58 Renewal Time RFC 2132 Yes Yes
59 Rebinding Time RFC 2132 Yes Yes
60 Class ID RFC 2132 Yes Yes
61 Client ID RFC 2132 Yes Yes
62 NetWareIP? Domain RFC 2132 Yes Yes
63 NetWareIP? Option RFC 2132 Yes Yes
64 NIS-Domain-Name RFC 2132 Yes Yes
65 NIS-Server-Addr RFC 2132 Yes Yes
66 Server-Name RFC 2132 Yes Yes
67 Bootfile-Name RFC 2132 Yes Yes
68 Home-Agent-Addrs RFC 2132 Yes Yes
69 SMTP Server RFC 2132 Yes Yes
70 POP3 Server RFC 2132 Yes Yes
71 NNTP Server RFC 2132 Yes Yes
72 WWW Server RFC 2132 Yes Yes
73 Finger Server RFC 2132 Yes Yes
74 IRC Server RFC 2132 Yes Yes
75 StreetTalk? Server RFC 2132 Yes Yes
76 STDA Server RFC 2132 Yes Yes
77 User Class RFC 3004 Yes Yes
78 Directory Agent RFC 2610 Yes Yes
79 Service Scope RFC 2610 Yes Yes
80 Rapid Commit RFC 4039 NA No
81 Client FQDN RFC 4702 Yes Yes
82 Relay Agent Information RFC 3046 Yes Yes
83 iSNS RFC 4174 No No
84 Unassigned
85 NDS Servers RFC 2241 Yes Yes
86 NDS Tree Name RFC 2241 Yes Yes
87 NDS Context RFC 2241 Yes Yes
88 BCMCS Controller Domain Name List RFC 4280 Yes Yes
89 BCMCS Controller IPv4 Address Option RFC 4280 Yes Yes
90 Authentication (Authentication in DHCPv4 is deprecated from a standards perspective) RFC 3118 No No*
91 Client Last Transaction Time RFC 4388 Yes No*
92 Associated Ip RFC 4388 Yes No*
93 Client System RFC 4578 Yes Yes
94 Client NDI RFC 4578 Yes Yes
95 LDAP RFC 3679 No No
96 Unassigned
97 UUID/GUID RFC 4578 Yes Yes
98 User Auth RFC 2485 Yes Yes
99 GEOCONF_CIVIC RFC 4776 Yes Yes
100 PCode RFC 4833 Yes Yes
101 TCode RFC 4833 Yes Yes
102 Unassigned
103 Unassigned
104 Unassigned
105 Unassigned
106 Unassigned
107 Unassigned
108 Unassigned
109 Unassigned
110 Unassigned
111 Unassigned
112 Netinfo Address RFC 3679 Yes Yes
113 Netinfo Tag RFC 3679 Yes Yes
114 URL RFC 3679 Yes Yes
115 Unassigned
116 Auto Config RFC 2563 Yes Yes
117 Name Service Search RFC 2937 Yes Yes
118 Subnet Selection Option RFC 3011 Yes Yes
119 Domain Search RFC 3397 Yes Yes
120 SIP Servers DHCP Option RFC 3361 No No
121 Classless Static Route Option RFC 3442 Yes Yes
122 CCC RFC 3495 No No
123 GeoConf? RFC 6225 No No
124 V-I Vendor Class RFC 3925 Yes Yes
125 V-I Vendor Specific Information RFC 3925 Yes Yes
126 Unassigned
127 Unassigned
128 PXE - undefined vendor specific RFC 4578 No No
129 PXE - undefined vendor specific RFC 4578 No No
130 PXE - undefined vendor specific RFC 4578 No No
131 PXE - undefined vendor specific RFC 4578 No No
132 PXE - undefined vendor specific RFC 4578 No No
133 PXE - undefined vendor specific RFC 4578 No No
134 PXE - undefined vendor specific RFC 4578 No No
135 PXE - undefined vendor specific RFC 4578 No No
136 Pana Agent RFC 5192 Yes Yes
137 V4 Lost RFC 5223 Yes Yes
138 Capwap AC V4 RFC 5417 Yes Yes
139 IPv4 Address MOS RFC 5678 No No
140 IPv4 FQDN MOS RFC 5678 No No
141 SIP UA Configuration Service Domains RFC 6011 Yes Yes
142 IPv4 Address ANDSF RFC 6153 Yes No
143 IPv6 Address ANDSF RFC 6153 No No
144 GeoLoc? RFC 6225 No No
145 Force Renew Nonce Capable RFC 6704 No No
146 RDNSS Selection RFC 6731 Yes Yes
147 Unassigned
148 Unassigned
149 Unassigned
150 TFTP Server Address RFC 5859 Yes No
151 status code RFC 6926 No No
152 base time RFC 6926 No No
153 start time of state RFC 6926 No No
154 query start time RFC 6926 No No
155 query end time RFC 6926 No No
156 dhcp state RFC 6926 No No
157 data source RFC 6926 No No
158 DCHPv4 PCP Server RFC 7291 No No
159 DHCPv4 Port Parameters RFC 7618 Yes Yes
160 DHCP Captive Portal RFC 7710 Yes Yes
161 MUD URL v4 RFC 8520 No No
162 Discovery of Network-designated Resolvers (DNR) RFC 9463 No Yes
163 Unassigned
164 Unassigned
165 Unassigned
166 Unassigned
167 Unassigned
168 Unassigned
169 Unassigned
170 Unassigned
171 Unassigned
172 Unassigned
173 Unassigned
174 Unassigned
175 Etherboot No No
176 IP Telephone No No
177 Etherboot No No
178 Unassigned
179 Unassigned
180 Unassigned
181 Unassigned
182 Unassigned
183 Unassigned
184 Unassigned
185 Unassigned
186 Unassigned
187 Unassigned
188 Unassigned
189 Unassigned
190 Unassigned
191 Unassigned
192 Unassigned
193 Unassigned
194 Unassigned
195 Unassigned
196 Unassigned
197 Unassigned
198 Unassigned
199 Unassigned
200 Unassigned
201 Unassigned
202 Unassigned
203 Unassigned
204 Unassigned
205 Unassigned
206 Unassigned
207 Unassigned
208 PXE Linux Magic RFC 5071 No No
209 Configuration File RFC 5071 No No
210 Path Prefix RFC 5071 No No
211 Reboot Time RFC 5071 No No
212 6RD RFC 5969 Yes Yes
213 V4 Access Domain RFC 5986 Yes Yes
214 Unassigned
215 Unassigned
216 Unassigned
217 Unassigned
218 Unassigned
219 Unassigned
220 Subnet Allocation RFC 6656 No No
221 Virtual Subnet Selection RFC 6607 No No
222 Unassigned
223 Unassigned
224 Reserved for private use
225 Reserved for private use
226 Reserved for private use
227 Reserved for private use
228 Reserved for private use
229 Reserved for private use
230 Reserved for private use
231 Reserved for private use
232 Reserved for private use
233 Reserved for private use
234 Reserved for private use
235 Reserved for private use
236 Reserved for private use
237 Reserved for private use
238 Reserved for private use
239 Reserved for private use
240 Reserved for private use
241 Reserved for private use
242 Reserved for private use
243 Reserved for private use
244 Reserved for private use
245 Reserved for private use
246 Reserved for private use
247 Reserved for private use
248 Reserved for private use
249 Reserved for private use
250 Reserved for private use
251 Reserved for private use
252 Reserved for private use
253 Reserved for private use
254 Reserved for private use
255 End RFC 2132 Yes Yes

DHCPv6 Options - updated 2024-01-29

code Name Reference DHCP Kea
0 Reserved
1 Client ID RFC 8415 Yes Yes
2 Server ID RFC 8415 Yes Yes
3 IA NA RFC 8415 Yes Yes
4 IA TA RFC 8415 Yes No*
5 IAADDR RFC 8415 Yes Yes
6 ORO RFC 8415 Yes Yes
7 Preference RFC 8415 Yes Yes
8 Elapsed Time RFC 8415 Yes Yes
9 Relay Message RFC 8415 Yes Yes
10 Unassigned
11 Auth RFC 8415 No No*
12 Unicast RFC 8415 Yes Yes
13 Status Code RFC 8415 Yes Yes
14 Rapid Commit RFC 8415 Yes Yes
15 User Class RFC 8415 No Yes
16 Vendor Class RFC 8415 No Yes
17 Vendor Options RFC 8415 Yes Yes
18 Interface ID RFC 8415 Yes Yes
19 Reconfigure Message RFC 8415 Yes No*
20 Reconfigure Accept RFC 8415 Yes No*
21 SIP Server Names RFC 3319 Yes Yes
22 SIP Server Addresses RFC 3319 Yes Yes
23 DNS Servers RFC 3646 Yes Yes
24 Domain List RFC 3646 Yes Yes
25 IA PD RFC 8415 Yes Yes
26 IAPREFIX RFC 8415 Yes Yes
27 NIS Servers RFC 3898 Yes Yes
28 NISP Servers RFC 3898 Yes Yes
29 NIS Domain Name RFC 3898 Yes Yes
30 NISP Domain Name RFC 3898 Yes Yes
31 SNTP Servers RFC 4075 Yes Yes
32 Information Refresh Time RFC 8415 Yes Yes
33 BCMCS Server D RFC 4280 Yes Yes
34 BCMCS Server A RFC 4280 Yes Yes
35 Unassigned
36 GEOCONF Civic RFC 4776 Yes Yes
37 Remote ID RFC 4649 Yes Yes
38 Subscriber ID RFC 4580 Yes Yes
39 Client FQDN RFC 4704 Yes Yes
40 PANA Agent RFC 5192 Yes Yes
41 New Posix TImezone RFC 4833 Yes Yes
42 New TZDB Timezone RFC 4833 Yes Yes
43 ERO RFC 4994 Yes Yes
44 LQ Query RFC 5007 Yes No*
45 Client Data RFC 5007 Yes No*
46 CLT Time RFC 5007 Yes No*
47 LQ Relay Data RFC 5007 Yes No*
48 LQ Client Link RFC 5007 Yes No*
49 MIPS6 HNIDF RFC 6610 No No
50 MIPB6 VDINF RFC 6610 No No
51 V6 Lost RFC 5223 Yes Yes
52 CAPWAP AC V6 RFC 5417 Yes Yes
53 Relay ID RFC 5460 Yes Yes
54 IPv6 Address MoS RFC 5678 No No
55 IPv6 FQDN MoS RFC 5678 No No
56 NTP Server RFC 5908 No No
57 V6 Access Domain RFC 5986 Yes Yes
58 SIP UA CS List RFC 6011 Yes Yes
59 Bootfile URL RFC 5970 Yes Yes
60 Bootfile Parameters RFC 5970 Yes Yes
61 Client Arch Type RFC 5970 Yes Yes
62 NII RFC 5970 Yes Yes
63 Geo Location RFC 6225 No No
64 AFTR Name RFC 6334 Yes Yes
65 ERP Local Domain Name RFC 6440 Yes Yes
66 RSOO RFC 6422 No Yes
67 PD Exclude RFC 6603 No Yes
68 VSS RFC 6607 No No
69 MIP6 IDINF RFC 6610 No No
70 MIP6 UDINF RFC 6610 No No
71 MIP6 HNP RFC 6610 No No
72 MIP6 HAA RFC 6610 No No
73 MIP6 HAF RFC 6610 No No
74 RDNSS Selection RFC 6731 Yes Yes
75 KRB Principal Name RFC 6784 No No
76 KRB Realm Name RFC 6784 No No
77 KRB Default Realm Name RFC 6784 No No
78 KRB KDC RFC 6784 No No
79 client-linklayer-addr RFC 6939 Yes Yes
80 link-address RFC 6977 Yes Yes
81 Radius RFC 7037 No No
82 solmax-rt RFC 8415 Yes Yes
83 inf-max-rt RFC 8415 Yes Yes
84 addrsel RFC 7078 No No
85 addrsel table RFC 7078 No No
86 v6 PCP server RFC 7291 No No
87 DHCPv4 msg RFC 7341 Yes Yes
88 dhcp4o6-server-addr RFC 7341 Yes Yes
89 OPTION_S46_RULE RFC 7598 No No*
90 OPTION_S46_BR RFC 7598 No No*
91 OPTION_S46_DMR RFC 7598 No No*
92 OPTION_S46_V4V6BIND RFC 7598 No No*
93 OPTION_S46_PORTPARAMS RFC 7598 No No*
94 OPTION_S46_CONT_MAPE RFC 7598 No Yes
95 OPTION_S46_CONT_MAPT RFC 7598 No Yes
96 OPTION_S46_CONT_LW RFC 7598 No Yes
97 OPTION_4RD RFC 7600 No
98 OPTION_4RD_MAP_RULE RFC 7600 No
99 OPTION_4RD_NON_MAP_RULE RFC 7600 No
100 OPTION_LQ_BASE_TIME RFC 7653 No
101 OPTION_LQ_START_TIME RFC 7653 No
102 OPTION_LQ_END_TIME RFC 7653 No
103 DHCP Captive Portal RFC 8910 Yes Yes
104 OPTION_MPL_PARAMETERS RFC 7774
105 OPTION_ANI_ATT RFC 7839
106 OPTION_ANI_NETWORK_NAME RFC 7839
107 OPTION_ANI_AP_NAME RFC 7839
108 OPTION_ANI_AP_BSSID RFC 7839
109 OPTION_ANI_OPERATOR_ID RFC 7839
110 OPTION_ANI_OPERATOR_REALM RFC 7839
111 OPTION_S46_PRIORITY RFC 8026 NA NA
112 OPTION_MUD_URL_V6 RFC 8520 NA NA
113 OPTION_V6_PREFIX64 RFC 8115
114 OPTION_F_BINDING_STATUS RFC 8156
115 OPTION_F_CONNECT_FLAGS RFC 8156
116 OPTION_F_DNS_REMOVAL_INFO RFC 8156
117 OPTION_F_DNS_HOST_NAME RFC 8156
118 OPTION_F_DNS_ZONE_NAME RFC 8156
119 OPTION_F_DNS_FLAGS RFC 8156
120 OPTION_F_EXPIRATION_TIME RFC 8156
121 OPTION_F_MAX_UNACKED_BNDUPD RFC 8156
122 OPTION_F_MCLT RFC 8156
123 OPTION_F_PARTNER_LIFETIME RFC 8156
124 OPTION_F_PARTNER_LIFETIME_SENT RFC 8156
125 OPTION_F_PARTNER_DOWN_TIME RFC 8156
126 OPTION_F_PARTNER_RAW_CLT_TIME RFC 8156
127 OPTION_F_PROTOCOL_VERSION RFC 8156
128 OPTION_F_KEEPALIVE_TIME RFC 8156
129 OPTION_F_RECONFIGURE_DATA RFC 8156
130 OPTION_F_RELATIONSHIP_NAME RFC 8156
131 OPTION_F_SERVER_FLAGS RFC 8156
132 OPTION_F_SERVER_STATE RFC 8156
133 OPTION_F_START_TIME_OF_STATE RFC 8156
134 OPTION_F_STATE_EXPIRATION_TIME RFC 8156
135 OPTION_RELAY_PORT RFC 8357
136 OPTION_V6_SZTP_REDIRECT RFC 8572
137 OPTION_S46_BIND_IPV6_PREFIX RFC 8539
138 OPTION_IA_LL RFC 8947
139 OPTION_LLADDR RFC 8947
140 OPTION_SLAP_QUAD RFC 8948
141 OPTION_V6_DOTS_RI RFC 8973
142 OPTION_V6_DOTS_ADDRESS RFC 8973
143 ANDSF IPv6 Address RFC 6153 Yes Yes
144 Discovery of Network-designated Resolvers (DNR) RFC 9463 No Yes
145 OPTION_REGISTERED_DOMAIN RFC 9527 section 4.1 No Work in progress
146 OPTION_FORWARD_DIST_MANAGER RFC 9527 section 4.2 No Work in progress
147 OPTION_REVERSE_DIST_MANAGER RFC 9527 section 4.3 No Work in progress
148 and larger currently unassigned

*These options are decoded but are not handled (the associated feature is unsupported).